Note: Descriptions are shown in the official language in which they were submitted.
81801244
INTEGRATED PROCESS DELIVERY AT VVELLSITE
[0001]
Background of the Disclosure
[0002] High viscosity fluid mixtures or gels comprising hydratable material
and/or additives
mixed with water and/or other hydrating fluid are utilized in fracturing and
other subterranean
well treatment operations. These high viscosity fluid mixtures are formulated
at the wellsite or
transported to the wellsite from a remote location. Hydration is a process by
which the
hydratable material solvates, absorbs, and/or otherwise reacts with hydrating
fluid to create the
high viscosity fluid mixture. The level of hydration of the hydratable
material may be increased
by maintaining the hydratable material in the hydrating fluid during a process
step referred to as
residence time, such as may take place in one or more hydration tanks.
[0003] Hydration and the associated increase in viscosity take place over a
time span
corresponding to the residence time of the hydratable material in the
hydrating fluid. Hence, the
rate of hydration of the hydratable material is a factor in the gelling
operations, and scrutinized in
continuous gelling operations by which the high viscosity fluid mixture is
continuously produced
at the job site during the course of wellsite operations. To achieve
sufficient hydration and/or
viscosity, long tanks or a series of large tanks are utilized to provide the
hydratable material with
sufficient volume and, thus, residence time in the hydrating fluid. Such tanks
are transported to
or near the wellsite. For example, the hydratable material may be mixed with
the hydrating fluid
before being introduced into a series of tanks and, as the fluid mixture
passes through the series
of tanks, the hydratable material may hydrate to a sufficient degree.
[0004] A typical gravity-flow hydration tank cannot handle a high
concentration fluid
mixture. Therefore, other tanks having large volumes are utilized to
sufficiently dilute
the fluid mixture to a sufficiently low viscosity to permit the fluid mixture
to pass
through the gravity-flow hydration tank. Hydration tanks having large volumes
comprise large footprints, are difficult to transport, and/or may not be
transportable.
High power mixers are then utilized to mix or blend the high viscosity fluid
mixtures with
proppant materials, solid additives, and liquid additives during blending
operations to form other
fluid mixtures, such as fracturing fluids.
[0005] Prior to blending, the proppant material and the solid additives are
transported to the
wellsite via delivery vehicles and fed into the mixers during the blending
operations. To avoid
interruptions in material supply, the delivery vehicles repeatedly arrive at
the wellsite, creating
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vehicle congestion. Furthermore, a limited number of delivery vehicles can be
parked on the
wellsite adjacent the mixers as the materials are unloaded and fed into the
mixers during
blending operations.
[0006] Separate pieces of equipment are utilized for performing gelling and
blending
operations. Such a functional split between equipment lends itself to
inefficiencies, reduced
reliability, exposure to non-standard rig-up, and poor process
controllability. With equipment
division of the gelling and blending units, duplicate pieces of equipment are
often utilized to
deliver the combined process, which increases the wellsite footprint and
complexity.
[0007] Each piece of equipment may also comprise its own engine, generator,
and/or other
power source, which is independently refueled, and which increases maintenance
activities.
Safety and environmental concerns are also higher, such as may be attributable
to the large and
numerous hoses, pipes, and/or other conduits connecting the various blending
and mixing
components, each of which is susceptible to leaks and non-standard rig-ups.
[0008] The gelling and blending operations are also becoming more complex as
they are
being tailored to specific subterranean reservoirs. This also adds to the
burden on the field
personnel and organization, increasing the multiple pieces of equipment that
are controlled and
maintained. Moreover, because the gelling and blending controls are highly
manual, the field
personnel and organization increasingly includes experienced, highly-trained
operators.
Summary of the Disclosure
[0009] This summary is provided to introduce a selection of concepts that
are further
described below in the detailed description. This summary is not intended to
identify
indispensable features of the claimed subject matter, nor is it intended for
use as an aid in
limiting the scope of the claimed subject matter.
[0010] According to an aspect of the present disclosure, there is provided
a method,
comprising: operating each of a plurality of first transfer mechanisms to
transfer a corresponding
material of a plurality of materials received from a corresponding delivery
vehicle of a plurality
of delivery vehicles to a corresponding container of a plurality of containers
at a wellsite,
wherein the plurality of delivery vehicles are driven over a corresponding
inlet of the plurality of
first transfer mechanisms to drop the corresponding material into the
corresponding inlet through
a chute of the corresponding delivery vehicle, and wherein each of the
plurality of materials has
a different composition; operating each of a plurality of second transfer
mechanisms to transfer a
corresponding material of the plurality of materials from a corresponding
container of the
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plurality of containers to a corresponding mixer of a mixing unit, wherein the
plurality of second
transfer mechanisms comprises a hydratable material transfer mechanism and a
proppant
material transfer mechanism; and operating each of the corresponding mixers of
the mixing unit
to at least partially form a substantially continuous stream of subterranean
formation fracturing
fluid utilizing each of the plurality of materials received from each of the
plurality of second
transfer mechanisms, by operating a first mixer of the mixing unit to form a
mixture comprising
hydratable material received from the hydratable material transfer mechanism
and discharging
the mixture under pressure into a hydrating system, wherein the hydrating
system comprises at
least one container defining a continuous flow channel therein to permit
adequate hydration of
the hydratable material to occur within the at least one container, and by
operating a second
mixer of the mixing unit to receive the hydrated mixture from the hydrating
system and combine
the mixture with proppant material received from the proppant material
transfer mechanism.
[0010a] According to another aspect of the present disclosure, there is
provided a method,
comprising: operating each of a plurality of first transfer mechanisms to
transfer a corresponding
material of a plurality of materials received from a corresponding delivery
vehicle of a plurality
of delivery vehicles to a corresponding container of a plurality of containers
at a wellsite,
wherein the plurality of delivery vehicles are driven over a corresponding
inlet of the plurality of
first transfer mechanisms to drop the corresponding material into the
corresponding inlet through
a chute of the corresponding delivery vehicle, and wherein each of the
plurality of materials has
a different composition; operating each of a plurality of second transfer
mechanisms to
substantially continuously transfer a corresponding material of the plurality
of materials from a
corresponding container of the plurality of containers to a corresponding
mixer of a mixing unit,
wherein the plurality of second transfer mechanisms comprises a hydratable
material transfer
mechanism and a proppant material transfer mechanism; and operating each of
the
corresponding mixers of the mixing unit to at least partially form a
substantially continuous
stream of subterranean formation fracturing fluid utilizing each of the
plurality of materials
received from each of the plurality of second transfer mechanisms, wherein
operating the mixing
unit to at least partially form the substantially continuous stream of
subterranean formation
fracturing fluid comprises: operating a first mixer of the mixing unit to form
a mixture
comprising hydratable material received from the hydratable material transfer
mechanism,
wherein the first mixer is connected with a frame; discharging the mixture
under pressure into a
hydrating system, wherein the hydrating system comprises at least one
container comprising a
substantially continuous flow pathway extending therethrough to permit
adequate hydration of
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the hydratable material to occur therein; operating a second mixer of the
mixing unit to receive
the hydrated mixture from the hydrating system and combine the mixture with
proppant material
received from the proppant material transfer mechanism, wherein the second
mixer is connected
with the frame; and discharging the substantially continuous stream of
subterranean formation
fracturing fluid from the mixing unit for further processing and/or injection
into a wellbore.
[0010b] The present disclosure introduces an apparatus that includes a mixing
unit having a
frame, a rheology control portion, and a high-volume solids blending portion.
The rheology
control portion includes means for receiving a first material from a first
transfer mechanism, a
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dispersing and/or mixing system connected with the frame, and a first metering
system to meter
the first material from the first material receiving means to the dispersing
and/or mixing system.
The dispersing and/or mixing system is operable to disperse and/or mix the
metered first material
with a fluid to form a first fluid mixture. The high-volume solids blending
portion includes
means for receiving a second material from a second transfer mechanism, a
solids blending
system connected with the frame, and a second metering system to meter the
second material
from the second material receiving means to the solids blending system. The
solids blending
system is operable to blend the metered second material with the first fluid
mixture to form a
second fluid mixture. The second material may be a high-volume solids
material, such as
proppant or other particulate material.
10011] The present disclosure also introduces a method in which first
transfer mechanisms
are operated to transfer corresponding materials received from corresponding
delivery vehicles
to corresponding containers. Each of the materials has a different
composition. Second transfer
mechanisms are operated to transfer corresponding ones of the materials from
corresponding
ones of the containers to a mixing unit. The mixing unit is operated to at
least partially form a
subterranean formation fracturing fluid utilizing each of the materials
received from each of the
second transfer mechanisms.
[0012] The present disclosure also introduces an apparatus that includes a
wellsite system for
utilization in a subterranean fracturing operation. The wellsite system
includes a mobile base
frame having an open area extending at least partially therethrough, and
multiple containers
disposed on the mobile base frame over the open area. The containers are for
containing high-
volume solid materials. The wellsite system also includes a mixing unit having
first and second
mixers. The mixing unit is operable to move within the open area such that,
within the open
area, a receiving means of the first mixer is aligned with a gravity-fed
discharge of the high-
volume solid materials from at least one of the containers.
[0013] The present disclosure also introduces a method that includes
deploying a mobile
base frame at a wellsite. The mobile base frame includes an open area
extending at least
partially therethrough. Multiple containers are erected on the mobile base
frame. The containers
are for containing high-volume solid materials. A mixing unit is transported
into the open area
such that material receiving means of the mixing unit align with a gravity-fed
discharge of the
high-volume solid materials from at least one of the containers. The mixing
unit includes a
frame, a first mixer connected with the frame, and a second mixer connected
with the frame and
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in fluid communication with the first mixer. The material receiving means
receive and direct
gravity-fed discharge of the high-volume solid materials to at least one of
the first and second
mixers.
[0014] These and additional aspects of the present disclosure are set forth
in the description
that follows, and/or may be learned by a person having ordinary skill in the
art by reading the
materials herein and/or practicing the principles described herein. At least
some aspects of the
present disclosure may be achieved via means recited in the attached claims.
Brief Description of the Drawings
[0015] The present disclosure is understood from the following detailed
description when
read with the accompanying figures. It is emphasized that, in accordance with
the standard
practice in the industry, various features are not drawn to scale. In fact,
the dimensions of the
various features may be arbitrarily increased or reduced for clarity of
discussion.
[0016] FIG. 1 is a schematic view of at least a portion of an example
implementation of
apparatus according to one or more aspects of the present disclosure.
[0017] FIG. 2 is a schematic view of at least a portion of an example
implementation of
apparatus according to one or more aspects of the present disclosure.
[0018] FIG. 3 is a schematic view of a portion of an example implementation
of the
apparatus shown in FIG. 2 according to one or more aspects of the present
disclosure.
[0019] FIG. 4 is a schematic view of a portion of an example implementation
of the
apparatus shown in FIG. 2 according to one or more aspects of the present
disclosure.
10020] FIG. 5 is an expanded view of an example implementation of a portion
of the
apparatus shown in FIG. 2 according to one or more aspects of the present
disclosure.
[0021] FIG. 6 is an expanded view of an example implementation of a portion
of the
apparatus shown in FIG. 2 according to one or more aspects of the present
disclosure.
[0022] FIG. 7 is a schematic view of an example implementation of a portion
of the
apparatus shown in FIG. 3 according to one or more aspects of the present
disclosure.
[0023] FIG. 8 is a schematic view of at least a portion of an example
implementation of an
apparatus according to one or more aspects of the present disclosure.
[0024] FIGS. 9-12 are flow-chart diagrams of at least portions of an
example implementation
of a process according to one or more aspects of the present disclosure.
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[0025] FIG. 13 is a perspective view of an example implementation of the
apparatus shown
in FIG. 1 according to one or more aspects of the present disclosure.
[0026] FIG. 14 is a perspective view of an example implementation of a
portion of the
apparatus shown in FIG. 13 according to one or more aspects of the present
disclosure.
[0027] FIG. 15 is a perspective view of at least a portion of an example
implementation of
apparatus according to one or more aspects of the present disclosure.
[0028] FIG. 16 is a perspective view of an example implementation of the
apparatus shown
in FIG. 15 according to one or more aspects of the present disclosure.
[0029] FIG. 17 is a perspective view of an example implementation of the
apparatus shown
in FIGS. 2, 3, and 4 according to one or more aspects of the present
disclosure.
[0030] FIG. 18 is a flow-chart diagram of at least a portion of an example
implementation of
a method according to one or more aspects of the present disclosure.
[0031] FIG. 19 is a flow-chart diagram of at least a portion of an example
implementation of
a method according to one or more aspects of the present disclosure.
[0032] FIG. 20 is a flow-chart diagram of at least a portion of an example
implementation of
a method according to one or more aspects of the present disclosure.
[0033] FIG. 21 is a flow-chart diagram of at least a portion of an example
implementation of
a method according to one or more aspects of the present disclosure.
[0034] FIG. 22 is a flow-chart diagram of at least a portion of an example
implementation of
a method according to one or more aspects of the present disclosure.
Detailed Description
[0035] It is to be understood that the following disclosure provides many
different
implementations, or examples, for implementing different features of various
implementations.
Specific examples of components and arrangements are described below to
simplify the present
disclosure. These are, of course, merely examples and are not intended to be
limiting. In
addition, the present disclosure may repeat reference numerals and/or letters
in the various
examples. This repetition is for simplicity and clarity, and does not in
itself dictate a relationship
between the various implementations and/or configurations discussed. Moreover,
the formation
of a first feature over or on a second feature in the description that follows
may include
implementations in which the first and second features are formed in direct
contact, and may also
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include implementations in which additional features may be formed interposing
the first and
second features, such that the first and second features may not be in direct
contact.
100361 FIG. 1 is a schematic view of at least a portion of an example
wellsite system 100
located on a wellsite surface 101 according to one or more aspects of the
present disclosure. The
wellsite system 100 comprises a mixing unit 200 operatively connected with a
plurality of bulk
containers 102 storing various fluids, solids, additives, particulate
materials, and/or other
materials (hereinafter referred to collectively as "plurality of materials")
via a plurality of
transfer mechanisms 104. The transfer mechanisms 104 are operable to transfer
or otherwise
convey the plurality of materials from corresponding ones of the bulk
containers 102 to the
mixing unit 200. The mixing unit 200 is operable to receive and mix or
otherwise blend the
plurality of materials to form one or more fluid mixtures, such as may form at
least a portion of a
substantially continuous stream of fracturing fluid utilized in subterranean
formation fracturing
operations.
[0037] For example, the wellsite system 100 may comprise a bulk container
110, such as a
silo or tank, for containing a hydratable material, such as gelling agents,
guar, polymers,
synthetic polymers, galactomannan, polysaccharides, cellulose, and clay, among
other examples.
The bulk container 110 may be operatively connected with the mixing unit 200
via a transfer
mechanism 112 extending between the bulk container 110 and the mixing unit
200. The transfer
mechanism 112 may include a metering feeder, a screw feeder, an auger, a
conveyor, and/or the
like, and may extend between the bulk container 110 and the mixing unit 200
such that an inlet
of the transfer mechanism 112 may be positioned generally below the bulk
container 110 and an
outlet may be positioned generally above the mixing unit 200. A blade
extending along a length
of the transfer mechanism 112, for example, may be operatively connected with
a motor operable
to rotate the blade. As the mixing unit 200 is operating, the rotating blade
may move the
hydratable material from the inlet to the outlet, whereby the hydratable
material may be dropped,
fed, or otherwise introduced into the mixing unit 200.
[0038] The transfer mechanism 112 may also or instead include a pneumatic
conveyance
system, wherein pressurized gas, such as air, is utilized to move the
hydrating material from the
bulk container 110 to the mixing unit 200. The pneumatic conveyance system may
comprise a
vacuum pump, which may generate a vacuum operable to draw the hydrating
material from the
bulk container 110 and transfer the hydrating material into the mixing unit
200 via a conduit
system.
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[0039] The bulk container 110 may be a mobile container or trailer, such as
may permit its
transportation to the wellsite surface 101. However, the bulk container 110
may be skidded or
otherwise stationary, and/or may be temporarily or permanently installed at
the wellsite surface
101.
[0040] The wellsite system 100 may further comprise a bulk container 120,
which may
include a plurality of tanks for storing liquid additives, such as
crosslinkers, breakers,
surfactants, clay stabilizers, hydrochloric acid, and friction reducers, among
other examples. The
bulk container 120 may be operatively connected with the mixing unit 200 via a
transfer
mechanism 122 extending between one or more of the bulk containers 120 and the
mixing unit
200. The transfer mechanism 122 may include one or more fluid conduits
extending between the
bulk container 120 and the mixing unit 200. The transfer mechanism 122 may
further comprise
one or more fluid pumps operable to transfer the liquid additive from the bulk
container 120 to
the mixing unit 200.
[0041] The bulk container 120 may form a portion of a mobile container or
trailer, such as
may permit transportation to the wellsite surface 101. However, the bulk
container 120 may be
skidded or otherwise stationary, and/or may be temporarily or permanently
installed at the
wellsite surface 101.
[0042] The wellsite system 100 may also comprise a bulk container 130,
which may include
a silo or bin for storing a high volume or bulk material (hereinafter referred
to as a solid
additive). The solid additive may be dry or partially dry and may include
fibrous materials, such
as fiberglass, phenol formaldehydes, polyesters, polylactic acid, cedar bark,
shredded cane stalks,
mineral fiber, and hair, among other examples. The solid additive may be
packaged into small
encapsulations, such as pouches, pellets, bags, and/or other packaging means,
which may
improve handling during the transfer process and/or flow inside the bulk
container 130, and
which may decrease dust generation. The packaging means may dissolve or break
up upon
introduction into the mixing unit 200.
[0043] The bulk container 130 may be operatively connected with the mixing
unit 200 via a
transfer mechanism 132 extending between the bulk container 130 and the mixing
unit 200. The
transfer mechanism 132 may include a metering feeder, a screw feeder, an
auger, a conveyor,
and/or the like, and may extend between the bulk container 130 and the mixing
unit 200 such
that an inlet of the transfer mechanism 132 may be positioned generally below
the bulk container
130 and an outlet may be positioned generally above the mixing unit 200. A
blade extending
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along a length of the transfer mechanism 132, for example, may be operatively
connected with a
motor operable to rotate the blade. As the mixing unit 200 is operating, the
rotating blade may
move the solid additive from the inlet to the outlet, whereby the solid
additive may be dropped,
fed, or otherwise introduced into the mixing unit 200.
[0044] The transfer mechanism 132 may also or instead include a gravity
conveyance
mechanism. For example, a lower portion of the bulk container 130 may comprise
a tapered
configuration terminating with a chute disposed generally above the mixing
unit 200 or within a
hopper or another material receiving portion of the mixing unit 200. During
mixing operations,
the chute may be opened and closed by an actuator to permit the solid
additives to be dropped,
fed, or otherwise introduced into the mixing unit 200. The bulk container 130
may be vertically
oriented and disposed at an elevated position above the mixing unit 200, such
as may permit the
mixing unit 200 to be positioned at least partially underneath the bulk
container 130. Such
implementation may permit the chute of the bulk container 130 to be disposed
above the mixing
unit 200 or within the material receiving portion of the mixing unit 200 to
permit the solid
additives to be dropped, fed, or otherwise introduced into the receiving
portion of the mixing unit
200. The bulk container 130 may be a mobile container or trailer, such as may
permit its
transportation to the wellsite surface 101. However, the bulk container 130
may be skidded or
otherwise stationary, and/or may be temporarily or permanently installed at
the wellsite surface
101.
[0045] The wellsite system 100 may also comprise a bulk container 140,
which may include
a plurality of silos or bins for storing particulate material. The particulate
material may be or
comprise a solid and/or dry material, such as a proppant material, including
sand, sand-like
particles, silica, and quartz, among other examples. The particulate material
may also or instead
comprise mica and/or fibrous materials. The particulate material may also be
encapsulated as
described above with respect to the solid additive materials. The particulate
material is also
referred to herein as high-volume solids.
[0046] The bulk container 140 may be operatively connected with the mixing
unit 200 via a
transfer mechanism 142 extending between the bulk container 140 and the mixing
unit 200. The
transfer mechanism 142 may include a metering feeder, a screw feeder, an
auger, a conveyor,
and the like, and may extend between the bulk container 140 and the mixing
unit 200 such that
an inlet of the transfer mechanism 142 may be positioned generally below the
bulk container 140
and an outlet may be positioned generally above the mixing unit 200. A blade
extending along a
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length of the transfer mechanism 142, for example, may be operatively
connected with a motor
operable to rotate the blade. As the mixing unit 200 is operating, the
rotating blade may move
the particulate material from the inlet to the outlet, whereby the particulate
material may be
dropped, fed, or otherwise introduced into the mixing unit 200.
[0047] The transfer mechanism 142 may also or instead include a gravity
conveyance
mechanism. For example, a lower portion of the bulk container 140 may comprise
a tapered
configuration terminating with a chute disposed generally above the mixing
unit 200 or within a
hopper or another material receiving portion of the mixing unit 200. During
mixing operations,
the chute may be opened and closed by an actuator to permit the particulate
material to be
dropped, fed, or otherwise introduced into the mixing unit 200. The bulk
container 140 may be
vertically oriented and disposed at an elevated position above the mixing unit
200, such as may
permit the mixing unit 200 to be positioned at least partially underneath the
bulk container 140.
Such configuration may permit the chute of the bulk container 140 to be
disposed above the
mixing unit 200 or within the material receiving portion of the mixing unit
200 to permit the
particulate material to be dropped, fed, or otherwise introduced into the
receiving portion of the
mixing unit 200.
[0048] The bulk container 140 may be a mobile container or trailer, such as
may permit its
transportation to the wellsite surface 101. However, the bulk container 140
may be skidded or
otherwise stationary, and/or may be temporarily or permanently installed at
the wellsite surface
101.
[0049] The wellsite system 100 may also comprise a bulk container 150,
which may include
a plurality of tanks for storing hydrating fluid, such as an aqueous fluid or
an aqueous solution
comprising water, among other examples. The bulk container 150 may be fluidly
connected with
the mixing unit 200 via a transfer mechanism 152 operable to transfer the
hydrating fluid from
the bulk container 150 to the mixing unit 200. The transfer mechanism 152 may
comprise one or
more fluid conduits extending between the bulk container 150 and the mixing
unit 200. The
transfer mechanism 152 may further comprise one or more fluid pumps operable
to transfer the
hydrating fluid from the bulk container 150 to the mixing unit 200.
[0050] The bulk container 150 may be a mobile container or trailer, such as
may permit its
transportation to the wellsite surface 101. However, the bulk container 150
may be skidded or
otherwise stationary, and/or may be temporarily or permanently installed at
the wellsite surface
101.
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[0051] The wellsite system 100 may further comprise a plurality of
additional transfer
mechanisms 106 operable to transfer or otherwise convey ones of the plurality
of materials from
corresponding ones of a plurality of delivery vehicles 108 to the
corresponding bulk containers.
In the example implementation depicted in FIG. 1, the transfer mechanisms 106
include a
transfer mechanism 162, a transfer mechanism 172, a transfer mechanism 182,
and a transfer
mechanism 192. During mixing operations, the delivery vehicles 108 may enter a
material
delivery area 103 of the wellsite surface 101 for unloading of the plurality
of materials. The
material delivery area 103 may be located adjacent each of the transfer
mechanisms 106 and
away from the mixing unit 200 and/or the bulk containers 102. The bulk
containers 102 may be
located between the mixing unit 200 and the material delivery area 103.
[0052] The hydratable material may be periodically delivered to the
wellsite surface 101 via
a delivery vehicle 160 comprising a container storing the hydratable material.
During delivery,
the delivery vehicle 160 may be positioned adjacent the transfer mechanism
162, such as may
permit the hydratable material to be conveyed by the transfer mechanism 162
from the delivery
vehicle 160 to the bulk container 110. For example, each delivery vehicle 160
may comprise a
container having a lower portion with a tapered configuration terminating in
one or more chutes.
During delivery, the chutes may be disposed above the inlet portion of the
transfer mechanism
162 and then opened to permit the hydratable material to be dropped, fed, or
otherwise
introduced into the transfer mechanism 162.
[0053] The transfer mechanism 162 may include a metering feeder, a screw
feeder, an auger,
a bucket conveyor, and/or the like. The transfer mechanism 162 may extend
between the
delivery vehicle 160 and the bulk container 110 such that an inlet of the
transfer mechanism 162
may be positioned generally below the delivery vehicle 160 and an outlet of
the transfer
mechanism 162 may be positioned generally above the bulk container 110. A
blade extending
along a length of the transfer mechanism 162, for example, may be operatively
connected with a
motor operable to rotate the blade, which may move the hydratable material
from the inlet to the
outlet, whereby the hydratable material may be dropped, fed, or otherwise
introduced into the
bulk container 110.
[0054] The transfer mechanism 162 may also or instead include a pneumatic
conveyance
system, wherein pressurized gas, such as air, is utilized to move the
hydratable material from the
delivery vehicle 160 to the bulk container 110. The pneumatic conveyance
system may
comprise a vacuum generator, such as may generate a vacuum operable to draw
the hydratable
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material from the delivery vehicle 160 and transfer the hydratable material
into the bulk
container 110 via a conduit system.
[0055] The container of the delivery vehicle 160 may be the bulk container
110. For
example, the delivery vehicle 160 may deliver a full bulk container 110 to the
wellsite surface
101 to be replaced or swapped out with an empty bulk container 110.
[0056] The liquid additive may be periodically delivered to the wellsite
surface 101 via a
delivery vehicle 170 comprising a container storing the liquid additive.
During delivery, the
delivery vehicle 170 may be positioned adjacent the transfer mechanism 172,
such as may permit
the liquid additive to be conveyed by the transfer mechanism 172 from the
delivery vehicle 170
to the bulk container 120.
[0057] The transfer mechanism 172 may include one or more fluid conduits
extending
between the delivery vehicle 170 and the bulk container 120. The transfer
mechanism 172 may
further comprise one or more fluid pumps operable to transfer the liquid
additive from the
delivery vehicle 170 to the bulk container 120.
[0058] The solid additive may be periodically delivered to the wellsite
surface 101 via a
delivery vehicle 180 comprising a container storing the solid additive. During
delivery, the
delivery vehicle 180 may be positioned adjacent the transfer mechanism 182,
such as may permit
the solid additive to be conveyed by the transfer mechanism 182 from the
delivery vehicle 180 to
the bulk container 130. For example, each delivery vehicle 180 may comprise a
container
having a lower portion with a tapered configuration terminating in one or more
chutes. During
delivery, the chutes may be disposed above the inlet portion of the transfer
mechanism 182 and
then opened to permit the solid additives to be dropped, fed, or otherwise
introduced into the
transfer mechanism 182.
[0059] The transfer mechanism 182 may include a dust free conveying
mechanism, a
metering feeder, a screw feeder, an auger, a bucket conveyor, and/or the like,
and may extend
between the delivery vehicle 180 and the bulk container 130 such that an inlet
of the transfer
mechanism 182 may be positioned generally below the delivery vehicle 180, and
an outlet of the
transfer mechanism 182 may be positioned generally above the bulk container
130. A blade
extending along a length of the transfer mechanism 182, for example, may be
operatively
connected with a motor operable to rotate the blade, which may move the solid
additive from the
inlet to the outlet, whereby the solid additive may be dropped, fed, or
otherwise introduced into
the bulk container 130.
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[0060] The transfer mechanism 182 may also or instead include a pneumatic
conveyance
system, wherein pressurized gas, such as air, is utilized to move the solid
additive from the
delivery vehicle 180 to the bulk container 130. The pneumatic conveyance
system may
comprise a vacuum generator, such as may generate a vacuum operable to draw
the solid
additive from the delivery vehicle 180 and transfer the solid additive into
the bulk container 130
via a conduit system.
[0061] The particulate material may be periodically delivered to the
wellsite surface 101 via
a delivery vehicle 190 comprising a container storing the particulate
material. During delivery,
the delivery vehicle 190 may be positioned adjacent the transfer mechanism
192, such as may
permit the particulate material to be conveyed by the transfer mechanism 192
from the delivery
vehicle 190 to the bulk container 140. For example, each delivery vehicle 190
may comprise a
container having a lower portion with a tapered configuration terminating in
one or more chutes.
During delivery, the chutes may be disposed above the inlet portion of the
transfer mechanism
192 and then opened to permit the particulate material to be dropped, fed, or
otherwise
introduced into the transfer mechanism 192.
[0062] The transfer mechanism 192 may include a metering feeder, a screw
feeder, an auger,
a bucket conveyor, and/or the like, and may extend between the delivery
vehicle 190 and the
bulk container 140 such that an inlet of the transfer mechanism 192 may be
positioned generally
below the delivery vehicle 190, and an outlet of the transfer mechanism 192
may be positioned
generally above the bulk container 140. A blade extending along a length of
the transfer
mechanism 192, for example, may be operatively connected with a motor operable
to rotate the
blade, which may move the particulate material from the inlet to the outlet,
whereby the
particulate material may be dropped, fed, or otherwise introduced into the
bulk container 140.
[0063] The transfer mechanism 192 may also or instead include a pneumatic
conveyance
system, wherein pressurized gas, such as air, is utilized to move the
particulate material from the
delivery vehicle 190 to the bulk container 140. The pneumatic conveyance
system may
comprise a vacuum generator, such as may generate a vacuum operable to draw
the particulate
material from the delivery vehicle 190 and transfer the particulate material
into the bulk
container 140 via a conduit system.
[0064] Although FIG. 1 shows each of the delivery vehicles 160, 170, 180,
190 as being
larger than some of the corresponding bulk containers 110, 120, 130, 140, it
is to be understood
that each of the bulk containers 110, 120, 130, 140 may have a storage
capacity that may be
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about equal to or greater than a storage capacity of the corresponding
delivery vehicle 160, 170,
180, 190. Accordingly, each of the bulk containers 110, 120, 130, 140 may be
operable to
receive therein an entire quantity of the corresponding material transported
by the corresponding
delivery vehicle 160, 170, 180, 190.
[0065] Furthermore, as the bulk containers 110, 120, 130, 140 may be
operable to store the
plurality of materials, the mixing unit 200 may be operable to substantially
continuously form
the one or more fluid mixtures when one or more of the transfer mechanisms 106
is not
transferring a corresponding material from a corresponding delivery vehicle
160, 170, 180, 190.
In other words, each of the transfer mechanisms 106 may be operable to
periodically or
intermittently transfer the corresponding materials from the delivery vehicles
160, 170, 180, 190
to the corresponding bulk containers 110, 120, 130, 140 while, at the same
time, the transfer
mechanisms 104 may be operable to substantially continuously transfer the
corresponding
materials from the corresponding bulk containers 110, 120, 130, 140 to the
mixing unit 200.
[0066] The wellsite system 100 may also comprise a power source 195, such
as may be
operable to provide centralized electric power distribution to the mixing unit
200 and/or other
components of the wellsite system 100. The power source 195 may be or comprise
an engine-
generator set, such as may include a gas turbine generator, an internal
combustion engine
generator, and/or other sources of electric power. Electric power may be
communicated between
the power source 195 and the mixing unit 200 and/or other components of the
wellsite system
100 via various electric conductors 197. The power source 195 may be disposed
on a
corresponding truck, trailer, and/or other mobile carrier, such as may permit
its transportation to
the wellsite surface 101. However, the power source 195 may be skidded or
otherwise
stationary, and/or may be temporarily or permanently installed at the wellsite
surface 101.
[0067] The wellsite system 100 may include more than one power source 195,
such as may
permit each power source 195 to be positioned at a closer proximity to the
point of power
utilization. For example, one power source 195 may be utilized to power one or
more of the
plurality of transfer mechanisms 106, while another power source 195 may be
utilized to power
the mixing unit 200 and/or one or more of the other plurality of transfer
mechanisms 104. Two
or more power sources 195 may also provide redundancy to the wellsite system
100.
[0068] The mixing unit 200 comprises a theology control portion 202. For
example, the
rheology control portion 202 may be operable disperse and hydrate the
hydratable material
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within the hydrating fluid to form a first fluid mixture, such as may be or
comprise that which is
known in the art as a gel or a slurry.
100691 The mixing unit 200 further comprises a high-volume solids blending
portion 210.
For example, the high-volume solids blending portion 210 may be operable to
blend the
discharge from the rheology control portion 202 with the liquid additives, the
solid additives,
and/or the particulate material to form a second fluid mixture, such as may be
or comprise that
which is known in the art as a fracturing fluid. The second fluid mixture may
then be discharged
from the mixing unit 200, such as for further processing and/or injection into
a wellbore during
fracturing and/or other wellsite operations.
[0070] The mixing unit 200 may further comprise a control portion 212. For
example, the
control portion 212 may be operable to monitor and control operational
parameters of the
plurality of components of the mixing unit 200, and perhaps other components
of the wellsite
system 100, to form the first and second fluid mixtures.
[0071] The wellsite system 100 is depicted in FIG. 1 and described above as
being operable
to store and mix the plurality of materials to form a fracturing fluid.
However, it is to be
understood that the wellsite system 100 may be operable to mix other fluids
and materials to
form other mixtures that may be pressurized and/or individually or
collectively injected into the
wellbore during other oilfield operations, such as drilling, cementing,
acidizing, and/or water jet
cutting operations, among other examples.
[0072] FIG. 2 is a schematic view of at least a portion of an example
implementation of the
mixing unit 200 according to one or more aspects of the present disclosure.
The mixing unit 200
may be utilized in various implementations of a wellsite. However, for the
sake of clarity and
ease of understanding, the mixing unit 200 is described below in the context
of the wellsite
system 100 shown in FIG. 1. Thus, the following description refers to FIGS. 1
and 2,
collectively.
[0073] The mixing unit 200 may comprise means 204 for receiving and/or
storing a first
solid material. The first solid material may be directed to the receiving
and/or storing means 204
via conventional and/or future-developed means. For example, the first solid
material may be
hydratable material received from the bulk container 110 via the transfer
mechanism 112.
[0074] The first solid material may then be transferred to a solids
dispersing and/or mixing
system 214. Such transfer may be at a predetermined rate, such as via
utilization of a solids
metering system 206.
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[0075] Water and/or other fluid may also be transferred to the solids
dispersing and/or
mixing system 214. For example, such fluid may be drawn or otherwise
transferred from a
suction manifold and/or other inlet(s) 218 of the mixing unit 200.
[0076] The solids dispersing and/or mixing system 214 may then be operated
to disperse the
first solid material within the fluid received from one or more of the inlets
218. For example, in
implementations in which the first solid material is guar or other hydratable
material, the solids
dispersing and/or mixing system 214 may mix the hydratable material with water
to form the
first fluid mixture described above.
[0077] The fluid discharged from the solids dispersing and/or mixing system
214 may then
be directed towards a hydrating system 220. For example, the hydrating system
220 may be a
first-in-first-out (FIFO) tank system comprising one or more hydration tanks,
and the first fluid
mixture discharged from the solids dispersing and/or mixing system 214 may be
directed through
the one or more hydration tanks of the hydrating system 220 to permit
hydration of the first fluid
mixture.
[0078] In the example implementation depicted in FIGS. 1 and 2, the
rheology control
portion 202 of the mixing unit 200 includes the container 204, the solids
metering system 206,
the solids dispersing and/or mixing system 214, and the hydrating system 220.
The rheology
control portion 202 may also include a metering system 245 for metering the
discharge of the
rheology control portion 202. However, the hydrating system 220 and the
metering system 245
are optional components, and may be omitted in some implementations of the
rheology control
portion 202.
[0079] The fluid discharged from the rheology control portion 202 may be
transferred to the
high-volume solids blending portion 210 of the mixing unit 200. For example,
the fluid
discharged from the rheology control portion 202 may be transferred into a
buffer tank 260 of the
high-volume solids blending portion 210. The mixing unit 200 may also comprise
a transfer
pump 240 operable to direct additional water (or other fluid from one or more
of the inlets 218)
to the buffer tank 260. The transfer pump 240 may also discharge to one or
more outlets 275 of
the mixing unit 200.
[0080] The high-volume solids blending portion 210 may comprise means 266
for receiving
and/or storing high-volume solids. The high-volume solids may be directed to
the receiving
and/or storing means 266 via gravity feeding, such as from a storage silo
located above the
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receiving and/or storing means 266. For example, the high-volume solids may be
particulate
material received from the bulk container 140.
[0081] The high-volume solids may then be transferred to a solids blending
system 265.
Such transfer may be at a predetermined rate, such as via utilization of a
high-volume solids
metering system 267. The high-volume solids blending portion 210 may include
more than one
solids blending system 265, and the transfer of the high-volume solids via the
high-volume solids
metering system 267 may be to one or more of the solids blending systems 265.
[0082] The high-volume solids blending portion 210 may also comprise means
280 for
receiving and/or storing a second solid material. The second solid may be
directed to the
receiving and/or storing means 280 conventional or future-developed means. For
example, the
second solid material may be received from the bulk container 130 via the
transfer mechanism
132.
[0083] The second solid material may then be transferred to one or more of
the solids
blending systems 265. Such transfer may be at a predetermined rate, such as
via utilization of
another solids metering system 281.
[0084] One or more of the solids blending systems 265 may then be operated
to blend two or
more of: the discharge from the rheology control portion 202 (such as via the
buffer tank 260);
the high-volume solids, and the second solid material. For example, in
implementations in
which the discharge from the rheology control portion 202 is hydrated gel and
the high-volume
solids comprise proppant or other particulate material, one or more of the
solids blending
systems 265 may mix the hydrated gel with the particulate material to form the
second fluid
mixture described above.
[0085] The fluid discharged from the high-volume solids blending portion
210 may be
discharged from the mixing unit 200 via one or more of the outlets 275.
Different ones of the
outlets 275 may be utilized for different mixtures discharged by the solids
blending systems 265.
The mixtures discharged from the solids blending systems 265 may be combined
or kept separate
prior to communication to the one or more outlets 275 for discharge from the
mixing unit 200.
[0086] The mixing unit 200 may also comprise one or more liquid metering
systems 208 for
selectively introducing one or more liquid additives into the operations
described above. For
example, the liquid metering systems 208 may selectively introduce one or more
liquid additives
into the fluid flowing from one or more of the inlets 218 into the solids
dispersing and/or mixing
system 214. The liquid metering systems 208 may also or instead selectively
introduce one or
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more liquid additives into the first fluid mixture discharged from the solids
dispersing and/or
mixing system 214, such as upstream of the hydrating system 220. The liquid
metering systems
208 may also or instead selectively introduce one or more liquid additives
into the fluid flowing
from one or more of the inlets 218 into the transfer pump 240. The liquid
metering systems 208
may also or instead selectively introduce one or more liquid additives into
the fluid discharged
from the rheology control portion 202 for utilization in one or more of the
solids blending
systems 265, such as downstream of the buffer tank 260. The liquid metering
systems 208 may
also or instead selectively introduce one or more liquid additives into the
fluid discharged from
the high-volume solids blending portion 210. However, these are merely
examples, and the
liquid metering systems 208 may introduce one or more liquid additives at
locations other than
as described above and shown in FIG. 2.
[0087] FIGS. 3 and 4 are collectively a schematic view of at least a
portion of an example
implementation of the mixing unit 200 shown in FIG. 2. FIG. 3 generally
depicts the rheology
control portion 202, and FIG. 4 generally depicts the high-volume solids
blending portion 210.
For the sake of clarity and ease of understanding, the mixing unit 200 is also
described below in
the context of the wellsite system 100 shown in FIG. 1. Thus, the following
description refers to
FIGS. 1-4, collectively.
[0088] FIG. 3 depicts the receiving and/or storing means 204 as being
implemented as a
hydratable material container 204, depicts the solids metering system 206 as
being implemented
as a hydratable material transfer device 206, and depicts the solids
dispersing and/or mixing
system 214 as being implemented as a first mixer 214 operable to receive and
mix hydratable
material and hydrating fluid. For example, the hydratable material may be
mixed with the
hydrating fluid at a rate of about 120 pounds of hydratable material per about
1000 pounds of
hydrating fluid, thus forming a 120-pound first fluid mixture. However, the
fluid formed and
discharged by the first mixer 214 may have between about 80 and about 300
pounds of
hydratable material per 1000 gallons of hydrating fluid, among other ratios
also within the scope
of the present disclosure.
[0089] The first mixer 214 may receive the hydratable material from the
hydratable material
container 204. The hydratable material container 204 may comprise a silo, bin,
hopper, and/or
another container that may permit storage of the hydratable material so as to
provide a
substantially continuous supply of the hydratable material to the first mixer
214. A lower portion
of the hydratable material container 204 may have a tapered configuration
terminating with a
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gate or other outlet permitting the hydratable material to be gravity fed
and/or otherwise
substantially continuously transferred into the first mixer 214. The
hydratable material may be
continuously or intermittently transported to the hydratable material
container 204 from the bulk
container 110 via the transfer mechanism 112.
[0090] The hydratable material may be metered and/or otherwise transferred
to the first
mixer 214 via the hydratable material transfer device 206. For example, if the
hydratable
material substantially comprises a liquid, the hydratable material transfer
device 206 may
comprise a metering pump and/or a metering valve, such as may be operable to
control the flow
rate at which the hydratable material is introduced into the first mixer 214.
[0091] However, if the hydratable material substantially comprises solid or
encapsulated
particles, the hydratable material transfer device 206 may comprise a
volumetric or mass dry
metering device operable to control the volumetric or mass flow rate of the
hydratable material
fed from the hydratable material container 204 to the first mixer 214. In such
implementations,
the hydratable material transfer device 206 may include a metering feeder, a
screw feeder, an
auger, a conveyor, and/or the like, and may extend between the hydratable
material container
204 and the first mixer 214 such that an inlet of the hydratable material
transfer device 206 may
be positioned generally below the hydratable material container 204, and an
outlet of the
hydratable material transfer device 206 may be positioned generally above the
first mixer 214. A
blade extending along a length of the hydratable material transfer device 206,
for example, may
be operatively connected with a motor operable to rotate the blade. As the
first mixer 214 is
operating, the rotating blade may move the hydratable material from the inlet
to the outlet,
whereby the hydratable material may be dropped, fed, or otherwise introduced
into the first
mixer 214.
[0092] In implementations in which the first mixer 214 is utilized to mix
hydratable material
and hydrating fluid to form a gel, for example, the first mixer 214 may be a
vortex type mixer as
further described below. However, as generally described above with respect to
FIG. 2, it is to
be understood that the first mixer 214 may be implemented as a chemical mixer
or other
"rheology modifier" operable to mix various rheology modifying materials, such
as may include
additives that provide high viscosity at low shear rates. Such rheology
modifiers may include the
hydratable material utilized to form gel, as described above. The rheology
modifiers may also
include additives like fiber, nanoscale particles, dry friction reducers,
dimeric and trimeric fatty
acids, imidazolines, amides, and/or synthetic polymers, among other examples
within the scope
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of the present disclosure. In such implementations, the first mixer 214 may be
a vortex type
mixer and/or other types of mixers.
[0093] Although not depicted in FIG. 3, the mixing unit 200 may comprise
more than one
hydratable material container 204 and corresponding transfer devices 206. For
example, the
mixing unit 200 may comprise a first hydratable material container 204 storing
hydratable
material that substantially comprises liquid, and a second hydratable material
container 204
storing hydratable material that substantially comprises solid particles. In
such implementations,
the hydratable material transfer device 206 corresponding to the first
hydratable material
container 204 may comprise a metering pump and/or a metering valve, and the
hydratable
material transfer device 206 corresponding to the second hydratable material
container 204 may
comprise a volumetric or mass dry metering device.
[0094] The hydratable material container 204 may comprise one or more force
sensors 216,
such as load cells and/or other sensors operable to generate information
related to mass or
another parameter indicative of the quantity of the hydratable material within
the hydratable
material container 204. Such information may be utilized to monitor the actual
transfer rate of
the hydratable material from the hydratable material container 204 into the
first mixer 214, to
monitor the accuracy of the hydratable material transfer device 206, and/or to
control the transfer
rate of the hydratable material discharged from the hydratable material
container 204 and/or the
hydratable material transfer device 206 for feeding to the first mixer 214.
[0095] FIG. 3 depicts the one or more inlets 218 of the mixing unit 200 as
being
implemented as a hydrating fluid source 218, such as may be operable to
receive the hydrating
fluid from the bulk container 150 via the transfer mechanism 152. The
hydrating fluid source
218 may comprise a receptacle, storage tank, reservoir, conduit, manifold,
and/or other
component for storing and/or receiving the hydrating fluid. For example, the
hydrating fluid
source 218 may comprise a plurality of inlet ports 249, such as may be
operable to fluidly
connect with the transfer mechanism 152 and receive the hydrating fluid from
the bulk container
150.
[0096] The supplied hydrating fluid may be drawn into the first mixer 214
via a suction force
generated by an impeller and/or other internal component of the first mixer
214. The suction
force may be sufficient to communicate the hydrating fluid from the hydrating
fluid source 218
to the first mixer 214. However, communication of the hydrating fluid from the
hydrating fluid
source 218 to the first mixer 214 may instead or also be facilitated by a pump
(not shown), such
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as may be operable to pressurize and/or move the hydrating fluid from the
hydrating fluid source
218 to the first mixer 214.
[0097] The mixing unit 200 may further comprise a plurality of valves
operable to control
flow of the hydrating fluid, a concentrated first fluid mixture discharged
from the first mixer 214,
or a diluted supply of the first fluid mixture, depending on their location.
The valves may
comprise ball valves, globe valves, butterfly valves, and/or other types of
valves operable to shut
off fluid flow or otherwise control fluid flow therethrough. The valves may be
actuated remotely
by an electric actuator, such as a solenoid or motor, or by a fluid actuator,
such as a pneumatic
cylinder or rotary actuator. The valves may also be manually actuated by a
human operator. For
example, the inlet ports 249 may be selectively opened and closed by a
plurality of
corresponding valves 239 disposed at each of the inlet ports 249, such as may
selectively permit
the transfer of hydrating fluid into the hydrating fluid source 218.
Similarly, another valve 219
may be fluidly connected between the hydrating fluid source 218 and the first
mixer 214, such as
may be operable to shut off or otherwise control the flow of the hydrating
fluid to the first mixer
214.
[0098] The mixing unit 200 may further comprise a plurality of pressure
sensors operable to
generate electric signals or information related to pressure of the hydrating
fluid, the
concentrated first fluid mixture, or the diluted first fluid mixture, at
various locations on the
mixing unit 200. For example, a pressure sensor 227 may be disposed at the
inlet of the first
mixer 214, such as may be operable to generate signals or information related
to pressure of the
hydrating fluid at the inlet of the first mixer 214.
[0099] The mixing unit 200 may also comprise a plurality of flow meters
operable to
generate electric signals or information related to flow rates of selected
fluids at a plurality of
locations on the mixing unit 200. For example, a flow meter 291 may be
disposed between the
hydrating fluid source 218 and the first mixer 214, such as may facilitate
monitoring the flow
rate of the hydrating fluid introduced into the first mixer 214.
[00100] The first mixer 214 may be operable to mix the hydratable material and
the hydrating
fluid, and to pressurize the resulting first fluid mixture sufficiently to
pump the first fluid mixture
through the hydrating system 220. FIG. 5 is an expanded view of an example
implementation of
at least a portion of the first mixer 214 according to one or more aspects of
the present
disclosure. The following description refers to FIGS. 3 and 5, collectively.
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[001011 The first mixer 214 may include a housing 302, a fluid inlet 304, and
a material inlet
306 extending into the housing 302. The fluid inlet 304 may be fluidly
connected with the
hydrating fluid source 218 for receiving hydrating fluid therefrom. The
material inlet 306 may
generally include or operate in conjunction with a receiving structure 308,
which may be or
include a cone, chamber, bowl, hopper, or the like. The receiving structure
308 may have an
inner surface 309 that receives materials (such as hydratable material
transferred from the
hydratable material container 204 via the hydratable material transfer device
206) for transfer
into the housing 302. The materials may be dry, partially dry, crystalized,
fluidic, pelletized,
encapsulated, and/or packaged materials, or may be liquid or slurry materials,
and/or other
materials to be dispersed within and/or otherwise mixed within the first mixer
214. The
materials received through the material inlet 306 may also be pre-wetted,
perhaps forming a
partial slurry, such as to avoid fisheyes and/or material buildup.
[00102] The first mixer 214 may further comprise an impeller/slinger assembly
310 driven by
a shaft 312. The housing 302 may define a mixing chamber 314 in communication
with the
inlets 304, 306, and the impeller/slinger assembly 310 may be disposed in the
mixing chamber
314. Rotation of the impeller/slinger assembly 310 may draw the hydrating
fluid from the fluid
inlet 304, mix the drawn hydrating fluid with the material fed from the
material inlet 306 within
the mixing chamber 314, and pump the resulting first fluid mixture through the
outlet 316. The
outlet 316 may direct the first fluid mixture through one or more fluid
conduits into the hydrating
system 220.
[00103] The shaft 312 may extend upward through the inlet 306 and out of the
receiving
structure 308 for connection with an electric motor and/or other prime mover
(not shown in FIG.
5). The shaft 312 may be connected with the impeller/slinger assembly 310 such
that rotation of
the shaft 312 rotates the impeller/slinger assembly 310 within the mixing
chamber 314.
[00104] The first mixer 214 may also include a stator 318 disposed around the
impeller/stator
assembly 310. The stator 318 may be in the form of a ring or arcuate portion,
example details of
which are described below.
[00105] The first mixer 214 may further comprise a flush line 320 fluidly
connected between
the receiving structure 308 and an area of the mixing chamber 314 that is
proximal to the
impeller/slinger assembly 310. The flush line 320 may tap the hydrating fluid
from the mixing
chamber 314 at an area of relatively high pressure and deliver it to the inner
surface 309 of the
receiving structure 308, which may be at a reduced (e.g., ambient) pressure.
In addition to being
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at the relatively high pressure, the hydrating fluid tapped by the flush line
320 may be relatively
"clean" (i.e., relatively low additives content, as will be described below).
As such, the
hydrating fluid tapped by the flush line 320 may be utilized to pre-wet the
receiving structure
308 and promote the avoidance of clumping of the material being fed through
the receiving
structure 308. The flush line 320 may provide the pre-wetting fluid without
utilizing additional
pumping devices (apart from the pumping provided by the impeller/slinger
assembly 310) or
additional sources of hydrating fluid or lines from the hydrating fluid source
218. However, one
or more pumps may be provided in addition to or in lieu of tapping the
hydrating fluid from the
mixing chamber 314.
[00106] The housing 302 may comprise an upper housing portion 322 and a lower
housing
portion 324. Connection of the upper and lower housing portions 322, 324 may
define the
mixing chamber 314 therebetween. The lower housing portion 324 may define a
lower mixing
area 326, and the upper housing portion 322 may define an upper mixing area
328 (shown in
phantom lines) that may be substantially aligned with the lower mixing area
326. The mixing
areas 326, 328 may together define the mixing chamber 314 in which the
impeller/slinger
assembly 310 and the stator 318 may be disposed. The lower housing portion 324
may also
include an interior surface 330 defining the bottom of the lower mixing area
326.
[00107] The upper housing portion 322 may be connected with the receiving
structure 308,
and may provide the material inlet 306. The lower housing portion 324 may
include the fluid
inlet 304, which may extend through the lower housing portion 324 to a
generally centrally
disposed opening 332. The opening 332 may be defined in the interior surface
330. The outlet
316 may extend from an opening 334 communicating with the lower mixing area
326.
[00108] The impeller/slinger assembly 310 may include a slinger 336 and an
impeller 338.
The slinger 336 and the impeller 338 may have inlet faces 340, 342,
respectively, and backs 344,
346, respectively. The inlet faces 340, 342 may be each be open (as shown) or
at least partially
covered by a shroud (not shown), which may form an inlet in the radially inner
part of the slinger
336 and/or impeller 338. The backs 344, 346 may be disposed proximal to one
another and
connected together, such that, for example, the impeller 338 and the slinger
336 may be disposed
in a "back-to-back" configuration. Thus, the inlet face 340 of the slinger 336
may face the
material inlet 306, while the inlet face 342 of the impeller 338 may face the
fluid inlet 304.
Accordingly, the inlet face 342 of the impeller 338 may face the interior
surface 330, and the
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opening 332 defined on the interior surface 330 may be aligned with a radially
central portion of
the impeller 338.
[00109] The slinger 336 may substantially define a saucer-shape generally
having a flatter (or
flat) middle portion with arcuate or slanted sides, collectively forming at
least a portion of the
inlet face 340. The sides may be formed, for example, as similar to or as part
of a torus that
extends around the middle of the slinger 336. The slinger 336 may also be bowl-
shaped (e.g.,
generally a portion of a sphere). The slinger 336 includes six stinger blades
348 on the inlet face
340, although other numbers of blades 348 are also within the scope of the
present disclosure.
The blades 348 may extend radially in a substantially straight or curved
manner. As the stinger
336 rotates, the material received from the material inlet 306 is propelled
radially outward, by
interaction with the blades 348, and axially upward, as influenced by the
shape of the inlet face
340.
[00110] Although obscured from view in FIG. 5, the impeller 338 may also
include one or
more blades on the inlet face 342. Rotation of the impeller 338 may draw
hydrating fluid
through the opening 332 and then expel the hydrating fluid axially downward
and radially
outward. Consequently, a region of relatively high pressure may develop
between the lower
housing portion 324 and the impeller 338, which may act to drive the hydrating
fluid around the
mixing chamber 314 and toward the slinger 336.
1001111 The flush line 320 may include an opening 350 defined in the lower
housing portion
324 proximal to this region of high pressure. For example, the opening 350 may
be defined in
the interior surface 330 at a position between the outer radial extent of the
impeller 338 and the
opening 332 of the fluid inlet 304. The flush line 320 may be or comprise a
conduit 352 fluidly
connected with an inlet 354 of the receiving structure 308, for example, such
that hydrating fluid
is transported from the opening 350 into the receiving structure 308 via the
conduit 352. The
hydrating fluid may then travel along a generally helical path along the inner
surface 309 of the
receiving structure 308, as a result of the rotation of the slinger 336 and/or
the shaft 312, until the
hydrating fluid travels through the material inlet 306 to the slinger 336.
Thus, the hydrating fluid
received through the inlet 354 may generally form a wall of fluid along the
inner surface 309 of
the receiving structure 308.
[00112] The flow rate of the hydrating fluid through the conduit 352 and,
thus, along the inner
surface 309 of the receiving structure 308, may be increased and decreased by
a flow control
device 217 (shown in FIG. 3). The flow control device 217 may comprise one or
more of
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various types of flow control valves, including needle valves, metering
valves, butterfly valves,
globe valves, or other valves operable to control the rate of fluid flow.
[00113] During operation, a pressure gradient may develop between the impeller
338 and the
lower housing portion 324, with the pressure in the fluid increasing radially
outward from the
opening 332. Another gradient related to the concentration of the material
(from the material
inlet 306) in the hydrating fluid may also develop in this region, with the
concentration of
material increasing radially outward. In some cases, a high-pressure head and
low concentration
may be the intended, so as to provide a flow of relatively clean fluid through
the flush line 320,
propelled by the impeller/slinger assembly 310. Accordingly, the opening 350
for the flush line
320 may be disposed at a point along this region that realizes an optimal
tradeoff between
pressure head of the hydrating fluid and concentration of the material from
inlet 306 in the
hydrating fluid received into the flush line 320.
[00114] The stator 318 may form a shearing ring extending around the
impeller/slinger
assembly 310 within the mixing chamber 314. For example, the stator 318 may be
held
generally stationary with respect to the rotatable impeller/slinger assembly
310, such as via
fastening with the upper housing portion 322. However, the stator 318 may
instead be supported
by the impeller/slinger assembly 310 and may rotate therewith. In either of
these example
implementations, the stator 318 may ride on the inlet face 340 of the slinger
336, or may be
separated therefrom.
[00115] The stator 318 may include first and second annular portions 356, 358,
which may be
formed integrally or as discrete components connected together. The first
annular portion 356
may minimize flow obstruction and may include a shroud 360 and posts 362
defining relatively
wide slots 364, such as to permit relatively free flow of fluid therethrough.
In contrast, the
second annular portion 358 may maximize flow shear, such as to promote
turbulent mixing. For
example, the second annular portion 358 may comprise a series of stator vanes
366 that are
positioned closely together, in contrast to the wide spacing of the posts 362
of the first annular
portion 356. Thus, narrow flowpaths 368 may be defined between the stator
vanes 366, in
contrast to the wide slots 364 of the first annular portion 356.
[00116] The sum of the areas of the flowpaths 368 may be less than the sum of
the areas of
the stator vanes 366. The ratio of the collective flow-obstructing area of the
stator vanes 366 to
the collective flow-permitting area of the flowpaths 368 may be about 1.5:1,
for example.
However, the ratio may range between about 1:2 and about 4:1, among other
examples within
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the scope of the present disclosure. The flow-obstructing area of each stator
vane 366 may be
greater than the flow-permitting area of each flowpath 368.
[00117] The stator vanes 366 may be disposed at various pitch angles with
respect to the
circumference of the stator 318. For example, the axially extending surfaces
of the stator vanes
366 may be substantially straight (e.g., substantially parallel to the
diameter of the stator 318) or
slanted (e.g., to increase shear), whether in or opposite the direction of
rotation of the
impeller/slinger assembly 310.
[00118] Returning to FIG. 3, the first mixer 214 may discharge the first fluid
mixture,
hereinafter referred to as a concentrated first fluid mixture, under pressure
into the hydrating
system 220. The hydrating system 220 is depicted in FIG. 3 as being
implemented as a plurality
of first containers 220. A valve 215 may be fluidly connected downstream from
the first mixer
214, such as may be operable to fluidly isolate the first mixer 214 from other
portions of the
mixing unit 200 and/or to control the flow of the concentrated first fluid
mixture discharged from
the first mixer 214. Another valve 225 may be fluidly connected along a fluid
bypass conduit
226, such as may petniit hydrating fluid or other fluid to bypass the first
mixer 214 during
mixing or other operations, such as during flushing operations. Another valve
221 may be
fluidly connected upstream from the first containers 220, such as may be
operable to control the
flow of the concentrated first fluid mixture into the first containers 220. A
pressure sensor 228
may be disposed at the outlet of the first mixer 214, such as may be operable
to generate signals
or information related to pressure of the concentrated first fluid mixture at
the outlet of the first
mixer 214.
[00119] Each of the first containers 220 may be or comprise a continuous flow
channel or
pathway for communicating or conveying the concentrated first fluid mixture
over a period of
time sufficient to permit adequate hydration to occur, such that the
concentrated first fluid
mixture may reach a predetermined level of hydration and/or viscosity. Each
first container 220
may have a first-in-first-out mode of operation, and may comprise a vessel-
type outer housing
enclosing a receptacle having an elongated flow pathway or space operable to
store and
communicate the concentrated first fluid mixture therethrough.
[00120] FIG. 6 is an expanded view of an example implementation of the first
container 220
according to one or more aspects of the present disclosure. The first
container 220 may comprise
a plurality of enclosures 410, 420, 430, 440, which include a first enclosure
410, a second
enclosure 420, and one or more intermediate enclosures 430, 440. The first
container 220 may
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further comprise a first port 412 disposed on an outer wall 414 of the first
enclosure 410 and
operable to receive the concentrated first fluid mixture, and a second port
422 disposed on an
outer wall 424 of the second enclosure 420 and operable to discharge the
concentrated first fluid
mixture after hydration. The ports 412, 422 may be flush with or extend
outward from the outer
walls 414, 424, including implementations in which the ports 412, 422 extend
outward in a
tangential direction relative to the outer walls 414, 424.
[00121] The enclosures 410, 420, 430, 440 may comprise separate chambers
through which
the concentrated first fluid mixture may travel a distance over a time period
sufficient for
adequate hydration to occur. The enclosures 410, 420, 430, 440 may
collectively be in fluid
communication, such as may permit the concentrated first fluid mixture to be
introduced into the
first container 220 via the first port 412 and then flow successively through
the first enclosure
410, the intermediate enclosure 430, the intermediate enclosure 440, and the
second enclosure
420, and then be discharged through the second port 422.
[00122] The first container 220 may further comprise a first plate 450
connected to the first
enclosure 410, such as to confine the concentrated first fluid mixture within
the first enclosure
410 while passing through the first enclosure 410. The first plate 450 may be
connected to the
first enclosure 410 by various means, including removable fasteners attaching
with a flange 418
of the first enclosure 410, welding, and/or other means, or may be formed as
an integrated
portion of the first enclosure 410. The enclosures 410, 420, 430, 440 may be
connected with one
another by same or similar means. For example, each of the enclosures 410,
420, 430, 440 may
comprise a flange 416, 418, 426, 428, 436, 438, 446, 448 extending along the
top and bottom of
the outer walls 414, 424, 434, 444, such as for receiving threaded fasteners
and/or other means
for securing the enclosures 410, 420, 430, 440 with one another.
[00123] Each of the enclosures 410, 420, 430, 440 may comprise an interior
space 460, 470,
480, 490. Each interior space 460, 470, 480, 490, may be or define at least
one continuous fluid
flow channel or other passageway 462, 472, 482, 492, respectively, each having
a length greater
than the circumferential length of the corresponding outer wall 414, 424, 434,
444. For example,
each passageway 462, 472, 482, 492 may be defined within the corresponding
interior space 460,
470, 480, 490 by a spiral or otherwise shaped wall 464. The passageways 462,
472, 482, 492
may be orientated and connected such that the first and second ports 412, 422
are in fluid
communication.
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[00124] For example, during hydration operations, the concentrated first fluid
mixture may be
introduced into the first port 412, travel through the passageway 462, and
exit or otherwise
discharge from the first enclosure 410 at a substantially central port 466
(shown in phantom
lines). The concentrated first fluid mixture may then flow into the first
intermediate enclosure
430 at a central end 484 of the passageway 482, travel through the passageway
482, and exit
from the first intermediate enclosure 430 into the second intermediate
enclosure 440 through a
port 486 (shown in phantom lines) extending vertically through the first
intermediate enclosure
430. The concentrated first fluid mixture may then travel through the
passageway 492 and exit
from the second intei _____________________________________________________
mediate enclosure 440 into the second enclosure 420 through a port 496
(shown in phantom lines) extending vertically through the second intermediate
enclosure 440.
The concentrated first fluid mixture may then flow though the passageway 472
and exit through
the second port 422.
[00125] Although FIG. 6 shows four enclosures 410, 420, 430, 440, the first
container 220
may comprise one, two, three, five, or more enclosures within the scope of the
present
disclosure. Furthermore, although FIG. 3 shows four first containers 220, the
mixing unit 200
may comprise one, two, three, five, or more first containers 220, which may be
connected in
parallel and/or series if, for example, additional flow rates and/or longer
hydration times are
intended.
[00126] When multiple first containers 220 are utilized, the mixing unit 200
may comprise a
plurality of pressure sensors 224 operable to generate signals or information
related to pressure
between instances of the first containers 220. The information generated by
the pressure sensors
224 may be utilized to determine the concentration, viscosity, and/or
hydration level of the
concentrated first fluid mixture as it is conveyed through the first
containers 220. Another
pressure sensor 229 may be disposed at the outlet of the most downstream first
container 220,
such as may be operable to generate signals or information related to pressure
of the
concentrated first fluid mixture at the outlet of the most downstream first
container 220. Each of
the first containers 220 may further comprise a relief or overflow conduit
222, which may be
selectively opened and closed by a corresponding valve 223. When opened, each
relief or
overflow conduit 222 may be operable to relieve pressure or convey the
concentrated first fluid
mixture from a corresponding first container 220 into a second container 260.
[00127] In implementations of the mixing unit 200 that utilize multiple
instances of the first
containers 220, one or more in-line shearing and/or other mixing devices (not
shown) may be
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fluidly connected between the first containers 220, such as to increase the
rate of hydration
within one or more of the first containers 220. Heat rejected from one or more
components of
the mixing unit 200 and/or other components of the wellsite system 100, such
as engines or
motors, may also or instead be transferred to one or more of the first
containers 220, such as to
heat the concentrated first fluid mixture within the one or more first
containers 220 to expedite
hydration.
[00128] Although the mixing unit 200 is shown comprising the hydrating
system/first
containers 220, some implementations of the mixing unit 200 may omit the
hydrating
system/first containers 220. For example, certain jobs or applications utilize
solid materials or
rheology modifiers that do not utilize hydration or hydration time.
Accordingly, the
concentrated first fluid mixture discharged from the first mixer 214 may
bypass the hydrating
system/first containers 220, or the hydrating system/first containers 220 may
be omitted from the
mixing unit 200.
[00129] After the concentrated first fluid mixture is discharged from the
first containers 220,
the concentrated first fluid mixture may be transferred or communicated
through a diluter 230.
FIG. 7 is a schematic view of an example implementation of the diluter 230
according to one or
more aspects of the present disclosure. Referring to FIGS. 3 and 7,
collectively, the diluter 230
may be operable to mix or otherwise combine the concentrated first fluid
mixture with additional
hydrating fluid or other aqueous fluid to dilute the concentrated first fluid
mixture or otherwise
reduce the concentration of the hydratable material in the concentrated first
fluid mixture to a
predetermined concentration level. The diluter 230 may be or comprise a fluid
junction, a tee
connection, a wye connection, an eductor, a mixing valve, an inline mixer,
and/or another device
operable to combine and/or mix two or more fluids.
[00130] As depicted in the example implementation of FIG. 7, the diluter 230
may comprise a
first passage 231 operable to receive a substantially continuous supply of the
concentrated first
fluid mixture, a second passage 232 operable to receive a substantially
continuous supply of the
hydrating fluid, and a third passage 233 operable to discharge a substantially
continuously supply
of a diluted first fluid mixture. The first passage 231 may be fluidly
connected with the outlet
port 422 of the most downstream first container 220 directly or via one or
more conduits
permitting the concentrated first fluid mixture to be transferred into the
diluter 230, as indicated
by arrow 236. The second passage 232 may be fluidly connected with the
hydrating fluid source
218 via one or more conduits permitting the hydrating fluid to be transferred
into the diluter 230,
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as indicated by arrow 237. The third passage 233 may be fluidly connected with
an inlet of the
second container 260 by one or more conduits permitting the diluted first
fluid mixture to be
transferred into the second container 260, as indicated by arrow 238.
[00131] The hydrating fluid may be communicated to the diluter 230 by the
transfer pump
240, which may be operable to pressurize and/or move the hydrating fluid from
the hydrating
fluid source 218 to the diluter 230. The transfer pump 240 may be or comprise
a centrifugal
pump or another type of pump operable to transfer or otherwise substantially
continuously move
the hydrating fluid from the source 218 to the diluter 230 and/or other
locations within the
mixing unit 200. For example, the transfer pump 240 may move the hydrating
fluid from the
source 218 at a flow rate ranging between about zero barrels per minute (BPM)
and about 150
BPM. However, the mixing unit 200 is scalable, and the transfer pump 240 may
be operable at
other flow rates.
[00132] The mixing unit 200 may also comprise a pressure sensor 235 at the
outlet of the
hydrating fluid source 218, such as may be operable to generate signals or
information related to
pressure of the hydrating fluid at the outlet of the hydrating fluid source
218. Another pressure
sensor 253 may be disposed at the inlet of the transfer pump 240, such as may
be operable to
generate signals or information related to pressure of the hydrating fluid at
the inlet of the
transfer pump 240. A valve 248 may be fluidly connected between the transfer
pump 240 and
the hydrating fluid source 218, such as may be operable to control the flow of
the hydrating fluid
from the hydrating fluid source 218 to the transfer pump 240 and/or to fluidly
isolate the
hydrating fluid source 218 from the transfer pump 240. A pressure sensor 254
may also be
disposed at the outlet of the transfer pump 240, such as may be operable to
generate signals or
information related to pressure of the hydrating fluid at the outlet of the
transfer pump 240.
[00133] The ratio of the concentrated first fluid mixture and the hydrating
fluid fed to the
diluter 230, which determines the concentration of the resulting diluted first
fluid mixture, may
be controlled by adjusting the metering system 245, which is depicted in FIG.
3 as being
implemented as a first flow control device 245 operable to control the flow of
the concentrated
first fluid mixture into the diluter 230. The ratio of the concentrated first
fluid mixture and the
hydrating fluid fed to the diluter 230 may also or instead be controlled by
adjusting a second
flow control device 250 operable to control the flow of the hydrating fluid
into the diluter 230.
For example, if the concentration of the diluted first fluid mixture is
selected to be decreased for
use downstream, relative to the current concentration of the diluted first
fluid mixture being
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discharged from the diluter 230, the concentration of the diluted first fluid
mixture may be
decreased by decreasing the flow rate of the concentrated first fluid mixture
into the diluter 230,
via operation of the first flow control device 245, and/or by increasing the
flow rate of the
hydrating fluid into the diluter 230, via operation of the second flow control
device 250. The
flow rate of the concentrated first fluid mixture into the diluter 230 may be
decreased by closing
or otherwise reducing the flow area of the first flow control device 245, and
the flow rate of the
hydrating fluid into the diluter 230 may be increased by opening or otherwise
increasing the flow
area of the second flow control device 250.
[00134] Similarly, if the concentration of the diluted first fluid mixture
is selected to be
increased for use downstream, relative to the current concentration of the
diluted first fluid
mixture being discharged from the diluter 230, the concentration of the
diluted first fluid mixture
may be increased by increasing the flow rate of the concentrated first fluid
mixture into the
diluter 230 and/or by decreasing the flow rate of the hydrating fluid into the
diluter 230. The
flow rate of the concentrated first fluid mixture into the diluter 230 may be
increased by opening
or otherwise increasing the flow area of the first flow control device 245,
and the flow rate of the
hydrating fluid into the diluter 230 may be decreased by closing or otherwise
decreasing the flow
area of the second flow control device 250.
[00135] The first and second flow control devices 245, 250 may comprise
various types of
flow control valves, including needle valves, metering valves, butterfly
valves, globe valves, or
other valves operable to control the rate of fluid flow therethrough. Each of
the flow control
devices 245, 250 may comprise a flow-disrupting member 246, 251, such as may
be a plate or
other member having a substantially circular configuration, and perhaps having
a central opening
or passageway 247, 252 extending therethrough. The flow-disrupting members
246, 251 may be
selectively rotatable relative to the passages 231, 232 to selectively change
the effective flow
area and/or rates of the passages 231, 232. Such rotation may be via operation
of corresponding
solenoids, motors, and/or other actuators (not shown). The flow-disrupting
members 246, 251
may also be utilized to introduce turbulence in the passing fluid flow, such
as may aid in mixing
and/or further hydrating the diluted first fluid mixture discharged from the
diluter 230.
[00136] FIG. 7 depicts the concentrated first fluid mixture being introduced
into the diluter
230 via the first passage 231 of the diluter 230, and the hydrating fluid
being introduced into the
diluter 230 via the second passage 232. However, the concentrated first fluid
mixture may
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instead be introduced via the second passage 232, and the hydrating fluid may
instead be
introduced via the first fluid passage 231.
[00137] As further shown in FIG. 3, a flow meter 292 may be disposed upstream
of the first
passage 231 of the diluter 230, such as may be operable to generate signals or
information
related to the flow rate of the concentrated first fluid mixture being
introduced into the diluter
230. Another flow meter 293 may be disposed upstream of the second passage 232
of the diluter
230, such as may be operable to generate signals or information related to the
flow rate of the
hydrating fluid being introduced into the diluter 230.
[00138] The mixing unit 200 may comprise a metering pump 241 upstream or
downstream of
the first flow control device 245, such as may be operable to transfer the
concentrated first fluid
mixture from the first container 220 to the diluter 230 at a predetermined
flow rate. The
metering system 245 shown in FIG. 2 may include both the first flow control
device 245 and the
metering pump 241 shown in FIG. 3. In other implementations, however, the
metering system
245 shown in FIG. 2 may include the metering pump 241 in lieu of the flow
control device 245
shown in FIG. 3.
[00139] The metering pump 241 may be a lobe pump, a gear pump, a piston pump,
or another
type of positive displacement pump operable to move liquids at a selected flow
rate. A pressure
sensor 242 may be disposed at the outlet of the metering pump 241, such as may
be operable to
generate signals or information related to pressure of the concentrated first
fluid mixture at the
outlet of the metering pump 241.
[00140] The mixing unit 200 may further comprise a fluid bypass conduit 243
that may permit
the concentrated first fluid mixture or other fluid to bypass the metering
pump 241 during mixing
or other operations, such as during flushing operations. A valve 244 may be
fluidly connected
along the fluid bypass conduit 243 to selectively open and close the fluid
bypass conduit 243.
[00141] During mixing or other operations, the concentrated first fluid
mixture may be
recirculated through the first containers 220 via a recirculation flow path
258 comprising one or
more pipes, hoses, and/or other fluid flow conduits, such as when an excess
supply of the diluted
first fluid mixture exists in the buffer tank 260, or to provide additional
hydration time for the
concentrated first fluid mixture. Accordingly, a valve 259 may be selectively
opened to permit
the concentrated first fluid mixture to recirculate through the recirculation
flow path 258 and
then the first containers 220. During such recirculation operations, the
metering pump 241 may
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be operable to recirculate or otherwise move the concentrated first fluid
mixture through the
recirculation flow path 258 and the first containers 220.
[00142] A third flow control device 255 may be disposed at the discharge or
downstream of
the diluter 230. The third flow control device 255 may be operable to increase
or decrease the
output rate of the diluted first fluid mixture discharged from the diluter 230
and introduced into
the buffer tank 260. It is noted that the combination of the first flow
control device 245 and the
metering pump 241 shown in FIG. 3, and/or other implementations of the
metering system 245
shown in FIG. 2, may be further operable to increase and decrease the
residence time of the
concentrated first fluid mixture in the first containers 220 and, thus,
increase the level of
hydration and viscosity of the concentrated first fluid mixture discharged by
the first containers
220. For example, slower flow rates may permit the concentrated first fluid
mixture to remain in
the first containers 220 for a longer period of time prior to introduction
into the diluter 230
and/or the buffer tank 260.
[00143] Similarly to the first and second flow control devices 245, 250,
the third flow control
device 255 may comprise a flow-disrupting member 256, such as may comprise a
plate or other
member having a substantially circular configuration, and perhaps having a
central opening or
passageway 257 extending therethrough. The flow-disrupting member 256 may be
selectively
rotatable relative to the third passage 233 to selectively change the
effective flow area and/or rate
of the third passage 233, perhaps in a manner similar to the selective
rotation of the flow-
disrupting members 246, 251. The flow-disrupting member 256 may also be
utilized to
introduce turbulence in the passing fluid flow, such as may aid in mixing
and/or further
hydrating the diluted first fluid mixture communicated to the second container
260.
[00144] The diluted first fluid mixture discharged by the diluter 230 may be
communicated to
the buffer tank 260, such as for storing a supply of the diluted first fluid
mixture prior to being
utilized in the high-volume solids blending portion 210. The buffer tank 260
may also permit the
diluted first fluid mixture to further hydrate prior to being discharged. The
buffer tank 260 may
be an open or enclosed vessel or tank comprising one or more spaces operable
to receive and
contain the diluted first fluid mixture. However, the buffer tank 260 may be
omitted if sufficient
hydration and/or viscosity level is achieved via one or more instances of the
first container 220
and/or the diluter 230. In such implementations, the diluted first fluid
mixture may be
communicated directly to the high-volume solids blending portion 210.
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[00145] The buffer tank 260 may comprise the same or similar structure and/or
function as the
first containers 220, or the buffer tank 260 may be implemented as another
type of first-in-first-
out vessel or tank, such as may provide additional hydration time for the
diluted first fluid
mixture. The buffer tank 260 may also comprise one or more fluid level sensors
262, such as
may be operable to generate signals or information related to the amount of
diluted first fluid
mixture contained within the buffer tank 260.
[00146] As described above, FIG. 4 generally depicts high-volume solids
blending portion
210 of the mixing unit 200. FIG. 4 depicts the solids blending systems 265 as
being
implemented as two second mixers 265 fluidly connected with the buffer tank
260 via one or
more supply conduits 270. Each of the second mixers 265 may comprise the same
or similar
structure and/or function as the first mixer 214, depicted in FIG. 5 and
described above.
However, the second mixers 265 may omit the stator 218 and/or the flush line
320. The mixing
unit 200 may also comprise one or more than two instances of the second mixers
265 within the
scope of the present disclosure.
[00147] Similarly to the first mixer 214, each second mixer 265 may be
operable to receive
fluid and solid materials and mix or otherwise blend the fluid and solid
materials to form a fluid
mixture. For example, the second mixers 265 may be operable to receive the
diluted first fluid
mixture from the rheology control portion 202, the solid additives from the
bulk container 130,
and the high-volume solids from the bulk container 140 to form the second
fluid mixture. As
described above, the second fluid mixture may include a fracturing fluid
utilized in subterranean
formation fracturing operations, a fluid mixture utilized in the fracturing
fluid, and/or other fluid
mixtures.
[00148] The diluted first fluid mixture may be communicated from the buffer
tank 260 to the
second mixers 265 through the one or more supply conduits 270 extending
therebetween. The
diluted first fluid mixture may be drawn through the supply conduits 270 and
into a fluid
material inlet of the second mixers 265 via a suction force generated by the
second mixers 265.
A flow meter 294 may be disposed along the supply conduit 270 downstream of
the second
container 260, such as may be operable to generate signals or information
related to the flow rate
of the diluted first fluid mixture being introduced into the second mixers 265
from the second
container 260.
[00149] The second mixers 265 may receive the high-volume solids from the
transfer
mechanism 142 via the receiving and/or storing means 266. The receiving and/or
storing means
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266 are depicted in FIG. 4 as being implemented as hoppers, bins, and/or other
containers
operable to capture and/or store the high-volume solids discharged by outlet
portions of the
transfer mechanism 142. A lower portion of the receiving and/or storing means
266 may be
tapered or otherwise permitting the high-volume solids to be gravity fed
and/or otherwise
substantially continuously transferred into a mixing chamber (not shown) of
the second mixers
265.
[00150] Prior to being introduced to the mixing chamber, the high-volume
solids metering
system 267 may meter and/or otherwise transfer the high-volume solids at a
selected rate. The
high-volume solids metering system 267 may be disposed within the receiving
and/or storing
means 266, and may include a metering feeder, a screw feeder, an auger, a
conveyor, and the
like, such as may permit a predetermined flow of the high-volume solids into
the mixing
chamber of the second mixers 265. The high-volume solids metering system 267
may include
metering gates within the containers of the receiving and/or storing means
266, such as may be
selectively opened or closed to selectively adjust the flow rate of the high-
volume solids into the
mixing chamber. The transfer mechanism 142 may be or comprise a lower portion
of the bulk
container 140 terminating within the receiving and/or storing means 266, such
as may permit the
high-volume solids to be gravity fed into the receiving and/or storing means
266.
[00151] The second mixers 265 may receive the solid additives from the
transfer device 132
via the receiving and/or storing means 280. The receiving and/or storing means
280 are depicted
in FIG. 4 as being implemented as hoppers, bins, and/or other containers be
operable to capture
and/or store the solid additives discharged by outlet portions of the transfer
device 132. A lower
portion of the receiving and/or storing means 280 may have a tapered
configuration terminating
with a gate or other outlet permitting the solid additives to be gravity fed
and/or otherwise
substantially continuously transferred into the solids metering system 281,
which may be
operable to meter and/or otherwise transfer the solid additive to the second
mixers 265. The
solids metering system 281 may include a screw feeder, an auger, a conveyor,
and the like, and
may extend between the receiving and/or storing means 280 and a solid material
inlet of the
second mixers 265.
[00152] The mixing unit 200 may further comprise pressure sensors 285, 286
located at the
inlets and the outlets of the second mixers 265, such as may be operable to
generate signals or
information related to fluid pressures at the inlets and outlets of the second
mixers 265. Valves
285, 286 may be fluidly connected at the inlets and outlets of the second
mixers 265, such as
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may be operable to control the flow of the diluted first fluid mixture and the
second fluid mixture
through the second mixers 265, and/or to fluidly isolate one or both of the
second mixers 265
from other portions of the mixing unit 200.
[00153] The mixing unit 200 may further comprise a densitometer 268 connected
at the
outlets of the second mixers 265. The densitometer 268 may be operable to
generate signals or
information related to density or the amount of particles in the second fluid
mixture, which may
include the amount of solid additive and high-volume solids. The densitometer
268 may emit
radiation that is absorbed by different particles in the second fluid mixture.
Different absorption
coefficients may exist for different particles, which may then be utilized to
translate the signals
or information to determine a density measurement.
[00154] The mixing unit 200 may also comprise flow meters 295 disposed at the
outlets of the
second mixers 265. The flow meters 295 may be operable to generate signals or
information
related to the flow rate of the second fluid mixture being discharged from
each of the second
mixers 265.
[00155] The liquid injection systems 208 shown in FIG. 2 are generally
depicted in FIG. 4 as
comprising one or more liquid additive supply conduits 272 for introducing
liquid additives to
the diluted first fluid mixture upstream from the second mixers 265 and/or to
the second fluid
mixture downstream from the second mixers 265. The liquid injection system 208
may be
fluidly connected with the transfer mechanism 122 to receive the liquid
additive from the bulk
container 120. The liquid additive may be transferred or otherwise moved
through the liquid
additive supply conduit 272 by a liquid additive pump 273. A three-way valve
274 may be
fluidly connected along the liquid additive supply conduit 272, such as may be
operable to
selectively control whether the liquid additive is introduced to the diluted
first fluid mixture
upstream of the second mixers 265 or to the second fluid mixture downstream of
the second
mixers 265. A flow meter 296 may be fluidly connected downstream of the liquid
additive pump
273, such as may be operable to generate signals or information related to
flow rate of the liquid
additive being introduced to the diluted first fluid mixture or the second
fluid mixture.
[00156] The liquid injection system 208 may comprise additional liquid
additive supply
conduits 272, pumps 273, and/or flow meters 296, which may be utilized when
additional and/or
different liquid additives are intended to be introduced into the diluted
first fluid mixture or the
second fluid mixture. The additional liquid additive supply conduits 272,
pumps 273, and/or
flow meters 296 may be operable to introduce the liquid additives at different
locations along the
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mixing unit 200. For example, the liquid additives may be introduced at the
inlet and/or outlet of
the first mixer 214, at the inlet to the pump 240, at the outlets of the
hydrating fluid source 218,
and at the inlets and/or outlets of the second mixers 265. For example, the
liquid injection
system 208 may be utilized to introduce a chemical into the hydrating fluid
source 218 to modify
the pH and other properties of the hydrating fluid, such as water.
[00157] The mixing unit 200 may further comprise a fluid bypass conduit 271,
such as may
permit the first diluted fluid mixture or other fluid to bypass the second
mixers 265 during
mixing or other operations, such as during flushing operations. A valve 269
may be fluidly
connected along a fluid bypass conduit 271 to selectively open and close the
fluid bypass conduit
271.
[00158] As the second mixers 265 form the second fluid mixture, the second
fluid mixture
may be substantially continuously discharged by the second mixers 265 and
communicated to a
discharge manifold or other outlets 275 before being injected downhole.
Although the mixing
unit 200 is shown comprising two second mixers 265, both second mixers 265 may
not be
utilized simultaneously and/or utilized to mix the same materials. For
example, the second
mixers 265 may be used to mix two different fluid mixtures, such as two
different fracturing
fluid chemistries, and discharge them out of the mixing unit 200 separately or
together. Such
"split stream operations" may be performed where one of the second mixers 265
discharges a
clean fluid (i.e., without proppant material), while the other one of the
second mixers 265
discharges a dirty fluid (i.e., with proppant material). Other operations
include feeding
compatible chemicals to both second mixers 265 separately and then mixing them
downstream to
create highway type proppant packs in slick water applications. Such
application may create, for
example, crosslink fluid islands full of proppant material within water like
base fluid.
[00159] The outlets 275 may comprise a plurality of outlet ports 276 operable
to discharge the
second fluid mixture and/or other mixtures from the mixing unit 200. The
outlet ports 276 may
be selectively opened and closed by a plurality of corresponding valves 277
disposed at each of
the outlet ports 276.
[00160] The outlets 275 may further comprise a plurality of additional valves
278, 279, such
as may be operable to selectively isolate one or more of the outlets 275
and/or to select the
source of fluid being discharged therefrom. For example, when the valves 278
are open and the
valves 279 are closed, the outlets 275 may be operable to discharge the second
fluid mixture
discharged from the second mixers 265. However, when the valves 279 are open
and the valves
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278 are closed, the outlets 275 may be operable to discharge the hydrating
fluid discharged from
the transfer pump 240.
[00161] The flow meters 291-296, the level sensors 262, the force sensors 216,
the
densitometer 268, and the pressure sensors may generate signals or information
related to
corresponding operational parameters (hereinafter referred to collectively as
"parameter
information"), as described above, and communicate the parameter information
to a controller
510. The parameter information may be utilized by the controller 510 as
feedback signals, such
as may facilitate a closed-loop control of the mixing unit 200. For example,
the parameter
information may be utilized to determine accuracy of the pumps 240, 241, 273
and/or the flow
control devices 245, 250, 255 and to adjust the flow rates of selected fluids,
such that the
concentrations and flow rates of the concentrated first fluid mixture, the
diluted first fluid
mixture, and second fluid mixture match setpoint values, which may be
predetermined, selected
by a human operator, and/or determined by the controller 510 during mixing
operations.
[00162] FIG. 8 is a schematic view of at least a portion of an example
implementation of the
controller 510 in communication with the transfer devices 206, 267, 281, the
mixers 214, 265,
the pumps 240, 241, 273, the flow control devices 217, 245, 250, 255, the flow
meters 291-296,
the valves, the force sensors 216, the level sensors 262, the pressure
sensors, and the
densitometer 268 (hereinafter referred to collectively as "mixing unit
components"), according to
one or more aspects of the present disclosure. Such communication may be via
wired and/or
wireless communication means. However, for clarity and ease of understanding,
such
communication means are not depicted in FIG. 4, and a person having ordinary
skill in the art
will appreciate that myriad means for such communication means are within the
scope of the
present disclosure.
[00163] The controller 510 may be operable to execute example machine-readable
instructions to implement at least a portion of one or more of the methods
and/or processes
described herein, and/or to implement a portion of one or more of the example
oilfield devices
described herein. The controller 510 may be or comprise, for example, one or
more processors,
special-purpose computing devices, servers, personal computers, personal
digital assistant (PDA)
devices, smartphones, internet appliances, and/or other types of computing
devices.
[00164] The controller 510 may comprise a processor 512, such as a general-
purpose
programmable processor. The processor 512 may comprise a local memory 514, and
may
execute coded instructions 532 present in the local memory 514 and/or another
memory device.
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The processor 512 may execute coded instructions 532 that, among other
examples, may include
machine-readable instructions or programs to implement the methods and/or
processes described
herein. The processor 512 may be, comprise, or be implemented by one or a
plurality of
processors of various types suitable to the local application environment, and
may include one or
more of general-purpose computers, special-purpose computers, microprocessors,
digital signal
processors (DSPs), field-programmable gate arrays (FPGAs), application-
specific integrated
circuits (ASICs), and processors based on a multi-core processor architecture,
as non-limiting
examples. Of course, other processors from other families are also
appropriate.
[00165] The processor 512 may be in communication with a main memory, such as
may
include a volatile memory 518 and a non-volatile memory 520, perhaps via a bus
522 and/or
other communication means. The volatile memory 518 may be, comprise, or be
implemented by
random access memory (RAM), static random access memory (SRAM), synchronous
dynamic
random access memory (SDRAM), dynamic random access memory (DRAM), RAMBUS
dynamic random access memory (RDRAM), and/or other types of random access
memory
devices. The non-volatile memory 520 may be, comprise, or be implemented by
read-only
memory, flash memory, and/or other types of memory devices. One or more memory
controllers
(not shown) may control access to the volatile memory 518 and/or the non-
volatile memory 520.
The processor 512 may be further operable to cause the controller 510 to
receive, collect, and/or
record the concentration and flow setpoints and/or other information generated
by the mixing
unit system components and/or other sensors onto the main memory.
[00166] The controller 510 may also comprise an interface circuit 524. The
interface circuit
524 may be, comprise, or be implemented by various types of standard
interfaces, such as an
Ethernet interface, a universal serial bus (USB), a third generation
input/output (3GI0) interface,
a wireless interface, and/or a cellular interface, among other examples. The
interface circuit 524
may also comprise a graphics driver card. The interface circuit 524 may also
comprise a
communication device, such as a modem or network interface card, such as to
facilitate exchange
of data with external computing devices via a network (e.g., via Ethernet
connection, digital
subscriber line (DSL), a telephone line, a coaxial cable, a cellular telephone
system, a satellite,
etc.).
[00167] One or more of the mixing unit components may be connected with the
controller 510
via the interface circuit 524, such as may facilitate communication
therebetween. For example,
one or more of the mixing unit components may comprise a corresponding
interface circuit (not
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shown), which may facilitate communication with the controller 510. Each
corresponding
interface circuit may permit signals or information generated by the mixing
unit components to
be sent to the controller 510 as feedback signals for monitoring and/or
controlling operation of
one or more of the mixing unit components, or perhaps the entirety of the
mixing unit 200. Each
corresponding interface circuit may permit control signals to be received from
the controller 510
by the various motors, drives, solenoids, and/or other actuators (not shown)
associated with ones
of the mixing unit components to control operation of the corresponding mixing
unit
components, such as to control operation of the entirety of the mixing unit
200.
[00168] One or more input devices 526 may also be connected to the interface
circuit 524.
The input devices 526 may permit a human operator to enter data and commands
into the
processor 512, such as may include a setpoint corresponding to a predetermined
concentration of
the hydratable material in the diluted first fluid mixture (hereinafter
referred to as the "first
concentration setpoint"), a setpoint corresponding to a predetermined
concentration of the
particulate material in the second fluid mixture (hereinafter referred to as
the "second
concentration setpoint"), and a setpoint corresponding to a predetermined flow
rate of the diluted
first fluid mixture formed by the mixing unit 200 (hereinafter referred to as
the "flow setpoint").
The input devices 526 may be, comprise, or be implemented by a keyboard, a
mouse, a
touchscreen, a track-pad, a trackball, an isopoint, and/or a voice recognition
system, among other
examples. One or more output devices 528 may also be connected to the
interface circuit 524,
such as to display the first and second concentration setpoints and the flow
setpoint and
information generated by one or more of the mixing unit components. The output
devices 528
may be, comprise, or be implemented by visual display devices (e.g., a liquid
crystal display
(LCD) or cathode ray tube display (CRT), among others), printers, and/or
speakers, among other
examples.
[00169] The controller 510 may also connect with one or more mass storage
devices 530
and/or a removable storage medium 534, such as may be or include floppy disk
drives, hard
drive disks, compact disk (CD) drives, digital versatile disk (DVD) drives,
and/or USB and/or
other flash drives, among other examples. The setpoints and parameter
information may be
stored on the one or more mass storage devices 530 and/or the removable
storage medium 534.
[00170] The coded instructions 532 may be stored in the mass storage device
530, the volatile
memory 518, the non-volatile memory 520, the local memory 514, and/or the
removable storage
medium 534. Thus, components of the controller 510 may be implemented in
accordance with
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hardware (perhaps implemented in one or more chips including an integrated
circuit, such as an
application specific integrated circuit), or may be implemented as software or
firmware for
execution by one or more processors. In the case of firmware or software, the
implementation
may be provided as a computer program product including a computer readable
medium or
storage structure embodying computer program code (i.e., software or firmware)
thereon for
execution by the processor 512.
[00171] The coded instructions 532 may include program instructions or
computer program
code that, when executed by the processor 512, cause the mixing unit 200 (or
at least
components thereof) to perform tasks as described herein. For example, the
coded instructions
532, when executed, may cause the controller 510 to receive and process the
first and second
concentration setpoints and the flow setpoint and, based on the setpoints,
cause the mixing unit
200 to form the diluted first fluid mixture having the predetermined
concentration of hydratable
material, the diluted first fluid mixture having the predetermined
concentration of particulate
material, and the second fluid mixture at the predetermined flow rate. When
executed, the coded
instructions 532 may cause the controller 510 to receive the parameter
information generated by
mixing unit components and process the parameter information as feedback
signals, such as may
facilitate a closed-loop control of the mixing unit 200 and/or the mixing unit
components. For
example, the information may be utilized determine accuracy of the pumps 240,
241, 273, and/or
the flow control devices 245, 250, 255 and to adjust the flow rates of
selected fluids, such that
the concentrations and flow rates of the concentrated first fluid mixture, the
diluted first fluid
mixture, and second fluid mixture match setpoint values selected by an
operator and/or other
setpoint values determined by the controller 510 during mixing operations.
[00172] Although flow and concentration setpoints are discussed herein, it is
to be understood
that the controller 510 may receive and process other setpoints within the
scope of the present
disclosure. The controller 510 may also monitor and control other parameters
and operations of
the mixing unit 200, such as may be implemented to form the second fluid
mixture.
[00173] FIGS. 9-12 are flow-chart diagrams of at least portions of an example
control process
600 stored as coded instructions 532 and executed by the controller 510 and/or
one or more other
controllers associated with the mixing unit components according to one or
more aspects of the
present disclosure. The following description refers to FIGS. 3, 4, and 8-12,
collectively.
[00174] The process 600 may be implemented by the mixing unit 200 to form the
diluted first
fluid mixture having the predetermined concentration of hydratable material,
the second fluid
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mixture having the predetermined concentration of particulate material, and
the diluted first fluid
mixture at the predetermined flow rate based on the first and second
concentration setpoints and
the flow setpoint entered into the controller 510. FIGS. 9-12 show portions of
the process 600,
which may comprise a series of interrelated stages or sub-processes 610, 620,
630, 640, 650,
660, 670, 680, wherein each such sub-process may employ a separate control
loop, such as a
proportional-integral-derivative (PID) control loop. For example, one or more
of the sub-
processes 610, 620, 630, 640, 650, 660, 670, 680 may utilize a control loop to
achieve an
intended output or result. The sub-processes 610, 620, 630, 640, 650 may be
interrelated as
depicted by arrows 622, 632, 642, 652 or otherwise.
[00175] The sub-process 610 may comprise a determination of a concentrated
first fluid
mixture ("CFFM") concentration setpoint and a dilution ratio. Inputs to this
sub-process may
include a first diluted fluid mixture ("DFFM") concentration setpoint 612
(hereinafter
"concentration setpoint") and a maximum first diluted fluid mixture flow rate
setpoint 614
(hereinafter "flow setpoint"), which may be compared with the information
generated by the
flow meter 294. The concentration and flow setpoints 612, 614 may be
predetermined or
selected parameters that are specific to a wellsite operation to be executed
utilizing the wellsite
system 100, such as a hydraulic fracturing operation. The concentration and
flow setpoints 612,
614 may be determined based on other information that is relevant to the
wellsite operation, such
as characteristics of a subterranean formation (e.g., size, location, content,
etc.) into which the
diluted first fluid mixture discharged by the mixing unit 200 is to be
injected. The concentration
and flow setpoints 612, 614 may be entered into the controller 510 in a
suitable manner, such as
via the input devices 526. The controller 510 may then determine and output
parameters, such as
may be utilized during hydration operations based on the entered concentration
and flow
setpoints 612, 614 and/or other inputs. The controller 510 may then
communicate the other
parameters to one or more equipment controllers (not shown) associated with
the mixing unit
components, which in turn, may implement additional sub-processes.
[00176] The sub-process 620 may comprise the control of the hydratable
material transfer
device 206 for transferring hydratable material to the first mixer 214. Inputs
to the sub-process
620 may include one or more outputs (i.e., setpoints) generated by the sub-
process 610, along
with an actual hydrating fluid flow rate 626 into the first mixer 214, as
determined by the flow
meter 291. Signals generated by the one or more force sensors 216, such as
load cells that
support the hydratable material container 204, may be utilized in the sub-
process 620 to ensure
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that an appropriate amount of hydratable material is being introduced into the
first mixer 214,
and/or to compare the expected amount of hydratable material with an actual
amount of
hydratable material introduced into the first mixer 214.
[00177] The sub-process 630 may comprise the determination of the first
diluted fluid mixture
flow rate setpoint, which includes determination of the concentrated first
fluid mixture flow rate
setpoint and the hydrating fluid flow rate setpoint (indicated in FIG. 9 as
"Dilution Rate
Setpoint"). The inputs to the sub-process 630 may include one or more of the
outputs generated
by the sub-process 610, along with a total hydrating fluid flow rate 634 into
the diluter 230, as
determined by the flow meters 291, 293, and a first diluted fluid mixture
level 636 in the second
container 260, as determined by the level sensor 262.
[00178] The sub-process 640 may comprise control of the concentrated first
fluid mixture
flow rate into the diluter 230, which may be a function of the flow control
device 245 and/or the
metering pump 241. The inputs to the sub-process 640 may include a
concentrated first fluid
mixture flow rate setpoint 642 generated by the sub-process 630, along with an
actual
concentrated first fluid mixture flow rate 644, as determined by the flow
meter 292.
[00179] The sub-process 650 may comprise control of the hydrating fluid flow
rate into the
diluter 230, such as to control dilution of the concentrated first fluid
mixture. Inputs to the sub-
process 650 may include a dilution rate setpoint 652 generated by the sub-
process 630, along
with a hydrating fluid flow rate 654 into the diluter 230, as determined by
the flow meter 293.
[00180] The sub-process 660 may comprise the control of the particulate
material ("PM")
transfer devices 267, which may be implemented as the metering gates operable
for metering the
particulate material into the second mixers 265. Inputs to the sub-process 660
may include a
particulate material concentration setpoint 662. Another input to the sub-
process 660 may
include the particulate material flow rate 664, which may be based on or
comprise the control
signal sent to the particulate material transfer devices 267. Another input
may include the signal
666 generated by the densitometers 268. The densitometer signal 666 may be
compared with the
particulate material setpoint 662.
[00181] The sub-process 670 may comprise the control of the solid additive
("SA") transfer
devices 281 for metering the solid additive into the second mixers 214. Inputs
to the sub-process
670 may include solid additive concentration setpoint 672. Another input to
the sub-process 670
may include the solid additive flow rate 674, which may be based on or
comprise the control
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signal sent to the solid additive transfer devices 281. The solid additive
flow rate 674 may be
compared with the solid additive concentration setpoint 672.
[00182] The sub-process 680 may comprise the control of the liquid additive
("LA") pump
273 for metering the liquid additive into the diluted first fluid mixture or
the second fluid
mixture. Inputs to the sub-process 680 may include a liquid additive
concentration setpoint 682.
Another input to the sub-process 680 may include the liquid additive flow rate
684, as
determined by the flow meter 296. The liquid additive flow rate 684 may be
compared with the
liquid additive concentration setpoint 682.
[00183]
Similarly to the concentration and flow setpoints 612, 614, the particulate
material
concentration setpoint 662, the solid additive concentration setpoint 672, and
the liquid additive
concentration setpoint 682 may be predetermined or selected parameters that
are specific to the
wellsite operation to be executed utilizing the wellsite system 100, such as a
hydraulic fracturing
operation. The setpoints 662, 672, 682 may be determined based on other
information that is
relevant to the wellsite operation, such as characteristics of a subterranean
formation (e.g., size,
location, content, etc.) into which the second fluid mixture discharged by the
mixing unit 200 is
to be injected. The setpoints 662, 672, 682 may be entered into the controller
510 in a suitable
manner, such as via the input devices 526, wherein the controller 510 may
determine and output
parameters utilized during mixing operations based on the entered setpoints
662, 672, 682,
and/or other inputs. The controller 510 may then communicate the other
parameters to one or
more equipment controllers (not shown) associated with the mixing unit
components.
[00184] FIG. 13 is a perspective view of an example implementation of the
wellsite system
100 located on a wellsite surface 101 shown in FIG. 1 according to one or more
aspects of the
present disclosure. The wellsite system 100 comprises the mixing unit 200
disposed within a
support structure 760 and operatively connected with the bulk containers
storing various fluids,
solid additives, and particulate materials (hereinafter referred to
collectively as "plurality of
materials") via transfer mechanisms (not shown) operable to transfer or
otherwise convey the
plurality of materials from the bulk containers to the mixing unit 200.
[00185] The bulk container 110 is depicted in FIG. 13 as a tank for storing
the hydratable
material. The bulk container 120 is depicted in FIG. 13 as a plurality of
tanks for storing the
liquid additives. The bulk container 130 is depicted in FIG. 13 as a vertical
silo for storing the
solid additives and disposed on top of the support structure 760. The bulk
container 140 is
depicted in FIG. 13 as a plurality of silos for storing the particulate
material, such as a proppant
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material, and disposed on top of the support structure 760. The bulk container
150 is depicted in
FIG. 13 as a plurality of tanks for storing the hydrating fluid.
1001861 As described above with respect to FIG. 1, the wellsite system 100
comprises a
plurality of transfer mechanisms operable to transfer or otherwise convey the
plurality of
materials from corresponding delivery vehicles 108 to the bulk containers 110,
120, 130, 140,
150. During mixing operations, the delivery vehicles 108 may enter a material
delivery area 103
of the wellsite surface 101 for unloading of the plurality of materials.
[00187] The hydratable material may be periodically delivered to the wellsite
via a delivery
vehicle (not shown in FIG. 13) comprising a container storing the hydratable
material. During
delivery, the delivery vehicle may be positioned adjacent a corresponding
transfer mechanism
(not shown in FIG. 13) in a manner permitting the hydratable material to be
conveyed by the
transfer mechanism from the delivery vehicle to the bulk container 110.
[00188] The liquid additive may be periodically delivered to the wellsite via
another delivery
vehicle (not shown in FIG. 13) comprising a container storing the liquid
additive. During
delivery, the delivery vehicle may be positioned adjacent a corresponding
transfer mechanism
(not shown in FIG. 13) in a manner permitting the liquid additive to be
conveyed by the transfer
mechanism from the delivery vehicle to the bulk container 120.
[00189] The solid additive may be periodically delivered to the wellsite via
delivery vehicle
180 comprising a container storing the solid additive. During delivery, the
delivery vehicle 180
may be positioned adjacent the transfer mechanism 182 in a manner permitting
the solid additive
to be conveyed by the transfer mechanism 182 from the delivery vehicle 180 to
the bulk
container 130.
[00190] The particulate material may be periodically delivered to the wellsite
via the delivery
vehicle 190 comprising a container storing the particulate material. During
delivery, the delivery
vehicle 190 may be positioned adjacent the transfer mechanism 192 in a manner
permitting the
particulate material to be conveyed by the transfer mechanism 192 from the
delivery vehicle 190
to the bulk container 140.
[00191] FIG. 13 depicts the delivery vehicles 180, 190 as being larger than
the bulk containers
130, 140. However, it is to be understood that the bulk containers 130, 140
have a storage
capacity that may be about equal to or greater than a storage capacity of the
corresponding
delivery vehicle 180, 190.
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[00192] FIG. 14 is a perspective view of at least a portion of the support
structure 760 shown
in FIG. 13. The support structure 760 may be transported onto the wellsite
surface 101 and may
comply with various state, federal, and international regulations for
transport over roadways and
highways. The following description refers to FIGS. 13 and 14, collectively.
[00193] The support structure 760 may include a support base 761, a frame
structure 762, a
gooseneck portion 763, and a plurality of wheels 764 for supporting the
support base 761, the
frame structure 762, and the gooseneck portion 763. The gooseneck portion 763
may be
attached to a prime mover (not shown) such that the prime mover may move the
support
structure 760 between various locations, such as between the wellsite surface
101 and another
wellsite surface. The support structure 760 may thus be transported to the
wellsite surface 101
and then set up to support one or more bulk containers 130, 140. Although the
depicted example
of the support structure 760 may support up to four bulk containers 130, 140,
it should be
understood that the support structure 760 may be configured to support more or
less of the bulk
containers 130, 140.
[00194] The support base 761 may include a first end 765, a second end 766,
and a top surface
767. The frame structure 762 may extend above the support base 761 to define a
passage 768
generally located between the top surface 767 of the support base 761 and the
frame structure
762. The frame structure 762 includes one or more silo-receiving regions 769
each configured to
receive a bulk containers 130, 140. For example, the frame structure 762 is
shown defining four
silo-receiving regions 769, each configured to support a corresponding one of
the bulk containers
130, 140.
[00195] The gooseneck portion 763 may extend from the first end 765 of the
support base
761. Axles 770 supporting wheels 764 may be located proximate the second end
766 of the
support base 761, proximate the first end 765 of the support base 761, and/or
at other locations
relative to the support base 761. Although FIG. 14 shows the support structure
760 comprising
two sets of wheels 764 and axles 770 (second axle obstructed from view), it
should be
understood that more than two sets of wheels 764 and axles 770, positioned at
various locations
relative to the support base 761, may be utilized.
[00196] The support structure 760 may further comprise a first extendable base
771 on one
side of the support base 761, and a second extendable base 772 on the opposing
side of the
support base 761. In such implementations, the first and second extendable
bases 771, 772 may
aid in laterally supporting or stabilizing the frame structure 762, and thus
the bulk containers
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130, 140, such as may aid in preventing the bulk containers 130, 140 and the
frame structure 762
from falling over. The first and second extendable bases 771, 772 may also
serve as a loading
base for a truck during mounting of the bulk containers 130, 140 onto the
support structure 760,
as explained below.
[00197] The first and second extendable bases 771, 772 may be movably
connected to the
frame structure 762 and the support base 761 via one or more mechanical
linkages 773, such that
the first and second extendable bases 771, 772 may be selectively positioned
between a
transportation configuration, with the bases 771, 772 in the raised position,
and an operational
configuration, with the bases 771, 772 in the lowered position, as shown in
FIG. 14. In the
operational configuration, the first and second extendable bases 771, 772 may
extend
substantially horizontally from the frame structure 762, such as may aid in
laterally supporting
the bulk containers 130, 140 and/or to provide a loading base for transports
(not shown) operable
to mount the bulk containers 130, 140 onto the support structure 760.
[00198] The frame structure 762 may comprise a plurality of frames 774, 775,
776, 777
interconnected by a plurality of struts 778. The frames 774, 775, 776, 777 may
be substantially
parallel to each other and may be substantially similar in construction and
function. Each frame
774, 775, 776, 777 may comprise a plurality of frame members, such as may be
connected to
form a closed structure surrounding at least a portion of the passage 768.
Each frame 774, 775,
776, 777 may form an arch, such as may increase the structural strength of
each frame 774, 775,
776, 777. Each frame 774, 775, 776, 777 may include an apex 779 located at the
top center of
each frame 774, 775, 776, 777, wherein each apex 779 may be connected with
another apex 779
by first and second connecting members 780, 781. Each frame 774, 775, 776, 777
may be
formed from suitable materials operable to support the load from the bulk
containers 130, 140.
For example, the frames 774, 775, 776, 777 may be constructed from steel
tubulars, I-beams,
channels, and/or other suitable material, and may be connected together via
various mechanical
fastening techniques, such as may utilize one or more threaded fasteners,
plates, welds, and/or
other connection means.
[00199] A first set of connectors 782 may be disposed at the apex 779 of each
frame 774, 775,
776, 777 within corresponding silo-receiving regions 769, wherein each of the
first set of
connectors 782 may couple or engage with a corresponding connector on the bulk
containers
130, 140 or a corresponding portion of the bulk containers 130, 140 during and
after installation.
A second set of connectors 783 may be disposed within the corresponding silo-
receiving regions
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769 on the first expandable base 771 and/or the second expendable base 772 at
a lower elevation
than the first set of connectors 782. Each of the second set of connectors 783
may couple or
engage with a corresponding connector on the bulk container 130, 140 or a
corresponding
portion of the bulk containers 130, 140 during and after installation.
[00200] The first and second sets of connectors 782, 783 within each of the
silo-receiving
regions 769 may be configured to attach to or otherwise engage the bulk
containers 130, 140.
Once the bulk container 130, 140 are connected with the connectors 782, 783 on
top of the frame
structure 762, the support base 761 and the first and second expandable bases
771, 772 may be
deployed to the operational configuration and the prime mover may be
disconnected from the
gooseneck portion 763 of the support structure 760. Thereafter, the gooseneck
portion 763 may
be manipulated to lie on the ground, perhaps substantially co-planar with the
support base 761,
such as to form a ramp to aid the positioning the mixing unit 200 at least
partially within the
passage 768, as shown in FIG. 13. The mixing unit 200 may be positioned within
the passage
768 defined by the frame structure 762 such that the solid material receiving
portion 266 is
aligned with respect to the transfer mechanism 132, 142, such as a discharge
chute, of the bulk
containers 130, 140 to enable gravity feed. Thereafter, the other transfer
mechanisms 112, 122
may be connected with the mixing unit 200.
[00201] FIGS. 15 and 16 are a perspective view of an example implementation of
at least a
portion of the transfer mechanisms 182, 192 shown in FIG. 1 according to one
or more aspects of
the present disclosure. The figures show the transfer mechanisms 182, 192
implemented as a
mobile transfer unit 720 comprising a chassis 722 supporting one or more
horizontal conveyor
systems 724 and a mast 726 supporting one or more vertical conveyor systems
728. The
following description refers to FIGS. 15 and 16, collectively.
[00202] The chassis 722 may be implemented as a plurality of interconnected
steel beams,
channels, I-beams, H-beams, wide flanges, universal beams, rolled steel
joists, or any other
suitable structures. The first end of the chassis 722 may comprise a gooseneck
portion 730
operable for connection with a prime mover, such as may permit the mobile
transfer unit 720 to
be pulled by the prime mover to the wellsite surface 101. The second end of
the chassis 722,
opposite the first end, may comprise a plurality of wheels 732 rotatably
connected to the chassis
722 and supporting the chassis 722 on the wellsite surface 101. The horizontal
conveyor systems
724 may extend between the first and second ends of the chassis 722. The
horizontal conveyor
systems 724 may include screw feeders, augers, conveyors, belts, and/or other
transfer means
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operable to move the solid additives and/or the particulate material. A
portion of the horizontal
conveyor systems 724 may be covered or enclosed by a shroud 740, while another
portion of the
horizontal conveyor systems 724 may extend through a material unloading
platform 734.
[00203] The material unloading platform 734 may be connected to and/or
disposed on the
chassis 722 adjacent the first end of the chassis 722. The material unloading
platform 734 may
cover or enclose a portion of the horizontal conveyor systems 724 and comprise
a plurality of
vertical openings 736 on a top surface thereof, such as may permit the solid
additives, the
particulate material, and/or other high volume or bulk material to be dropped,
fed, or otherwise
introduced onto the horizontal conveyor systems 724 extending through or
underneath the
material unloading platform 734. The material unloading platform 734 may
further include one
or more ramps 738, which may help the delivery vehicles 180, 190 to move over
or onto the
material unloading platform 734 and permit alignment of the container chutes
191 of the delivery
vehicles 180, 190 above the openings 736. The ramps 738 may be pivotably or
otherwise
movably connected with the material unloading platform 734. During delivery,
the chutes may
be disposed above the openings 736 and then opened to permit the solid
additives and/or the
particulate material to be dropped, fed, or otherwise introduced onto the
horizontal conveyor
systems 724.
[00204] As further shown in FIGS. 15 and 16, the mast 726 may be pivotably
connected with
the chassis 722 via one or more mechanical linkages and, along with the
vertical conveyor
systems 728, may be movable between raised and lowered positions via one or
more actuators
742 extending between the mast 726 and the chassis 722. The mechanical
linkages may be
implemented in a variety of manners, such as rails, hydraulic or pneumatic
arms, gears, worm
gear jacks, cables, or combinations thereof. In some implementations the
actuators 742 may be
hydraulic or pneumatic actuators. The mast 726 may be implemented as a
plurality of
interconnected steel beams, channels, I-beams, H-beams, wide flanges,
universal beams, rolled
steel joists, or any other suitable structures. The vertical conveyor systems
728 may include
screw feeders, augers, belts, conveyors, bucket elevators, belts, pneumatics,
and/or other transfer
means operable to move the solid additives and/or the particulate material
vertically. The
vertical conveyor systems 728 may also be covered or enclosed by one or more
shrouds 744.
[00205] The mast 726 and the vertical conveyor systems 728 may be configured
to lay
substantially parallel with the chassis 722, and supported, at least in part,
by the gooseneck
portion 730 when the mobile transfer unit 720 is transported. The range of
motion of the mast
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726 and the vertical conveyor systems 728 may extend from substantially
horizontal to slightly
past vertical (e.g., more than a 90 degree range of motion) when deployed to
account for angular
misalignment due to ground height differences.
[00206] During operations, the horizontal conveyor systems 724 may be operable
to move the
solid additives and/or the particulate material introduced through the
openings 736 toward the
vertical conveyor systems 728. As the solid additives and/or the particulate
material reaches the
end of the horizontal conveyor systems 724, the solid additives and/or the
particulate material
may be transferred onto the vertical conveyor systems 728 and moved in the
upward direction.
For example, the horizontal conveyor systems 724 may terminate with one or
more outlets 746,
which may peiinit the transfer means to drop, feed, or otherwise introduce the
solid additives
and/or the particulate material into one or more inlets 748 of the vertical
conveyor systems 728.
The inlets 748, in turn, may direct the solid additives and/or the particulate
material onto the
transfer means of the vertical conveyor systems 728 to be moved vertically
toward outlets 750 of
the vertical conveyor systems 726.
[00207] Once the solid additives and/or the particulate material reach the top
of the vertical
conveyor systems 728, upper conveyor systems 752 may be operable to move the
solid additives
and/or the particulate material from the vertical conveyor systems 728 into
the bulk containers
130, 140. For example, the upper conveyor systems 752 may comprise auger
conveyors 754
driven by motors 756 to move the solid additives and/or the particulate
material horizontally
away from the vertical conveyor system 728. The upper conveyor system 752 may
comprise
inlets (obstructed from view), which may be operable to receive the solid
additives and/or the
particulate material from the outlets 750 of the vertical conveyor systems 728
and direct the solid
additives and/or the particulate material to the auger conveyors 754. The
upper conveyor system
752 may further comprise outlets 758, which may be disposed above or otherwise
aligned with
the inlets to the bulk containers 130, 180, such as may be operable to direct
the solid additives
and/or the particulate material from the upper conveyor system 752 into the
bulk containers 130,
180.
[00208] FIG. 17 is a perspective view of an example implementation of the
mixing unit 200
shown in FIGS. 1-4 and 13 according to one or more aspects of the present
disclosure. The
mixing unit 200 is depicted in FIG. 17 as being implemented as a mobile mixing
unit detachably
connected with a prime mover 701. The mixing unit 200 comprises a mobile
carrier 702 having
a frame 704 and a plurality of wheels 706 rotatably connected to the frame 704
and supporting
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the frame 704 on the wellsite surface 101. The mobile mixing unit 200 may
further comprise a
control cabin 708, which may be referred to in the art as an E-house,
connected with the frame
704. The control cabin 708 may comprise one or more controllers, such as the
controller 510
shown in FIGS. 4 and 8, and which may be operable to monitor and control the
mixing unit 200
as described above.
[00209] The hydratable material container 204 is depicted in FIG. 17 as being
implemented as
a hopper or bin operable to receive hydratable material therein. The
hydratable material
container 204 is connected to the frame 704 by, for example, a plurality of
support members 710.
[00210] The mixing unit 200 further comprises the first mixer 214 and the
hydratable material
transfer device 206, such as a screw feeder and/or other device operable to
meter the hydratable
material into the first mixer 214. The first mixer 214 is connected with the
frame 704 and
comprises a motor 712 operable to drive the first mixer 214. The first mixer
214 may be or
comprise the solid-fluid first mixer 214 as depicted in FIG. 5 or another
mixer operable to mix or
blend hydrating fluid with hydratable material. The hydrating fluid may be
supplied to the first
mixer 214 from the hydrating fluid source 218, which is depicted in FIG. 13 as
being
implemented as a manifold operable to receive hydrating fluid via the ports
249. Each of the
ports 249 may comprise a valve 239, such as may be operable to control the
flow of hydrating
fluid into the hydrating fluid source 218.
[00211] After the hydratable material and hydrating fluid are blended within
the first mixer
214 to form the concentrated first fluid mixture, the concentrated first fluid
mixture may be
communicated into and through one or more instances of the first container
220. The first
container 220 is depicted in FIG. 13 as being implemented as four enclosed
hydrating containers
each comprising a substantially continuous flow pathway extending
therethrough, such as the
example implementation depicted in FIG. 6. Thus, each first container 220 may
comprise first
and second ports 412, 422 operable to receive or discharge the concentrated
first fluid mixture
into or from each first container 220. Each first container 220 may be
connected to the frame
704 by, for example, a plurality of support members 714.
[00212] After the concentrated first fluid mixture is passed through the first
containers 220,
the concentrated first fluid mixture may be communicated into the second
container 260, which
is depicted in FIG. 17 as being implemented as a header tank. The second
container 260 may be
connected to the frame 704 by, for example, a plurality of support members
716.
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[00213] Prior to being introduced into the second container 260, additional
hydrating fluid
may be combined with or added to the concentrated first fluid mixture via the
diluter 230
(obscured from view in FIG. 13). The hydrating fluid may be transferred from
the hydrating
fluid source 218 to the diluter 230 by the pump (obscured from view in FIG.
13). The hydrating
fluid and the concentrated first fluid mixture may be combined within the
diluter 230 to form the
first diluted fluid mixture, as described above, and communicated into the
second container 260.
[00214] The diluted first fluid mixture may be discharged from the second
container 260 and
introduced into the second mixers 265 via a supply conduit 270. The
particulate material may be
introduced to the second mixers 265 via the solid material receiving portion
266, and the solid
additives may be introduced to the second mixers 265 via the additional solid
material receiving
portions 280.
[00215] FIG. 17 also depicts the liquid injection system 208, which may be
utilized to
introduce the liquid additives to the diluted first fluid mixture or the
second fluid mixture. As the
diluted first fluid mixture, the solid additives, the liquid additives, and
the particulate material are
substantially continuously mixed within the second mixers 265, the second
fluid mixture is
substantially continuously transferred to the discharge manifold 275. When the
valves 277 open,
the second fluid mixture may be discharged from the discharge manifold 275 via
the ports 276.
The wellsite system 100 may also comprise at least one bulk liquid chemicals
storage container,
such as may be operable to gravity feed liquid chemicals to the liquid
injection system 208 via a
hose assembly.
[00216] FIG. 17 also depicts the power source 195 described above, such as may
be operable
to provide centralized electric power distribution to the mixing unit 200
and/or other components
of the wellsite system 100. Utilizing the centralized electric power source
195 at the wellsite to
drive one or more pieces of backside process equipment of the wellsite system
100 may make the
mixing unit components power agnostic, whether an onsite diesel generator is
being utilized or
the power is obtained from the area power distribution network. It is to be
noted that the
centralized power may also be hydraulic. Utilization of centralized power may
aid in increasing
overall system reliability, whereas utilizing individual prime movers (e.g.,
diesel engines) on
each piece of equipment may adversely affect system reliability, increase
environment footprint,
increase maintenance cost, and/or limit equipment capabilities.
[00217] The mixing unit 200 may be an intelligent piece of process equipment
comprising the
metering, mixing, and blending functions that may utilize precision control,
calibration, and
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specialized machinery to deliver the fracturing fluid. Peripheral equipment,
such as the bulk
containers (i.e., bulk containers 102), may be kept basic for storage and
gravity feed, utilizing
minimal supervision and controls. The mixing unit 200 may also comprise a
motor control
center within or adjacent the control cabin 708, which may control the
electric motors driving the
mixers (i.e., first and second mixers 214, 265) and metering equipment (i.e.,
material transfer
devices 206, 267, 281), on the mixing unit 200.
[00218] The example mobile implementation of the mixing unit 200 depicted in
FIG. 17
combines gel mixing and solids blending on a single frame or chassis (i.e.,
frame 704). Such
integration may aid in providing process piping standardization, a reduced
footprint, improved
reliability, reduced health, safety, and environment (HSE) exposure, and/or
improved
controllability. The mixing unit 200 may serve as a standardized backside
manifold, and may be
the one wet piece of process equipment on location where the gel mixing,
solids blending, and
the liquid and dry additives metering takes place.
[00219] The mixing unit 200 may also reduce duplication of pumps (i.e.,
hydrating fluid pump
260, metering pump 261) to transfer fluids from one piece of equipment to
another. For
example, the first mixer 214 may be utilized as to transfer the hydrating
fluid from the bulk
containers 150 to the mixing unit 200, the metering pump 241 may transfer the
first mixture from
the first containers 220 to the second container 260, and the hydrating fluid
pump 240 may
transfer the hydrating fluid from the bulk containers 150 to the second
container 260.
Duplication of suction and discharge manifolds may thus be reduced.
[00220] The mixing unit 200 may further comprise built-in system redundancies.
For
example, the first mixer 214 may serve as a backup to a failed external
hydrating fluid transfer
pump.
[00221] The mixing unit 200 may also combine multiple instances of liquid
injection systems
208 in a single unit. The mixing unit 200 may deliver chemistry processes for
heterogeneous
proppant and/or fiber pulsing techniques where, in addition to proppant
pulsing, gel
concentration may be pulsed or slick water pumped with certain additives, on
one side of the
second mixer 265, may be combined with cross linked gel, pumped on the other
side of the
second mixer 265, to generate heterogeneous fluid at the discharge.
[00222] The mixing unit 200 may include at least one low volume solids-liquid
mixing
system, which may utilize certain hydration time, and at least one high volume
solids-liquid
mixing system, which may be executed one after the other or independently and
delivered to the
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discharge piping either separately or together. The low volume solids-liquid
mixing system may
have an option of using multiple types of solids simultaneously. Similarly, a
high volume solids-
liquid mixing system may blend multiple solids simultaneously. The mixing unit
200 may
include a storage capacity for low volume solids and/or liquids utilized for
preparing the
fracturing fluid.
[00223] The mixing unit 200 may be operable for multiple different job types,
such as a slick
water dirty job, a slick water split-stream job, a cross-link job, and a
hybrid job. For example,
the mixing unit 200 may be utilized in slick water jobs that, instead of gel,
utilize water with
multiple additives at a high rate. In dirty operations, the water may be
transferred into the
second container 260, and the flow control device 250 may be a proportional
flow control valve
utilized to control the flow rate of water into the second container 260 to
match the flow rate into
one or both of the second mixers 265. The fluid level within the second
container 260 may be
maintained, and a control loop may be utilized to fine tune the proportional
control valve to
make up the difference in level from a target value to an actual value. A
suitable feedback or
control loop may be utilized, such as PID control loop.
[00224] Such control may also be utilized for split-stream operation (SSO)
jobs. However,
less than 100% of the flow may be communicated through the second mixers 265.
For example,
a predetermined split between clean to dirty, such as 60:40, may be utilized.
The hydrating fluid
pump 260 may also discharge water into the discharge manifold 275 directly.
Valving may
ensure that the clean and dirty operations are not mixed unless intended. The
gel forming
components may be entirely shut off and not utilized. However, in the event of
transfer pump
failure, the first mixer 214 may instead be utilized as a redundancy.
[00225] During crosslink jobs, the gel forming components may be activated.
The
concentrated first fluid mixture being metered by the metering pump 261 may be
displaced into a
location downstream. The resulting flow dynamics may permit homogenous mixing
of the two
fluids, and the diluted first fluid mixture may be communicated into the
second container 260.
The downstream process may remain the same. For controls, the suction flow
rate of the first
mixer 214 may be utilized to meter the guar or other hydratable material into
the first mixer 214
to achieve a selected concentration. The ratio of corresponding flows may be
kept fixed to
achieve the selected concentration of the diluted first fluid mixture
communicated into the
second container 260. The flow rate downstream of the second container 260 may
be utilized as
a target for the total flow rate into the second container 260. This may aid
in maintaining a
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substantially constant level inside the second container 260 under steady
state. However, due to
transients, the level inside the second container 260 may drop or rise from an
optimal level.
Thus, a control loop may be utilized to achieve a proper rate at the inlet of
the second container
260.
[00226] In the event of a failure of a major component, such as the pump
240, the conduits
associated with the first mixer 214 may be configured to permit fluid (e.g.,
water or other
hydrating fluid) to be displaced directly into the second container 260, thus
bypassing the first
containers 220 and the pump 241, such as to permit the well to be flushed.
Another system
backup may regard failure of the pump 241, in which case the pump 241 may be
bypassed and
the flow control device 245 may be utilized to meter the first fluid mixture.
If operation of the
first mixer 214 is stopped, the pump 241 may enter recirculation with the
first containers 220,
such as to maintain motion of the entire volume. If suction of the first mixer
214 is found to be
insufficient in terms of suction from the bulk containers 150, the discharge
of the pump 240 may
also be utilized to boost the suction side of the first mixer 214, such as may
provide a net positive
suction head.
[00227] FIG. 18 is a flow-chart diagram of at least a portion of an example
implementation of
a method (810) according to one or more aspects of the present disclosure. The
method (810)
may be performed utilizing at least a portion of one or more implementations
of the apparatus
shown in one or more of FIGS. 1-17 and/or other apparatus within the scope of
the present
disclosure.
[00228] The method (810) comprises establishing (812) centralized electric
power at a
wellsite. For example, establishing (812) centralized electric power may
comprise installing
and/or activating the centralized power source 195 described above, such as by
connecting with a
local electrical grid, starting a gen-set, and/or otherwise. The centralized
electric power may be
established (812) to drive one or more components of the mixing unit 200 shown
in one or more
of FIGS. 1-4, 8, 13, and 17, one or more components of the mobile transfer
unit 720 shown in
FIGS. 15 and 16, and/or other equipment shown in FIG. 1 and/or 13.
[00229] The method (810) also comprises activating (814) a centralized
controller. For
example, the centralized controller may be the controller 510 described above.
The centralized
controller may be part of a centralized motor control house integrated to one
or more pieces of
equipment to distribute power and control material handling, fluid handling,
mixing, metering,
blending, conditioning, and/or transferring functions utilized to prepare
fracturing fluid at the
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wellsite. For example, the centralized motor control house may be the control
cabin 708
described above. The centralized controller may be or comprise a local control
system, such as
the controller 510 and/or other controllers implemented on or more components
at the wellsite,
that may interface with prime movers, power supply components, valves,
actuators, process
monitoring systems, sensors, and/or other components, and that may provide
setpoints and
system level job parameters.
[00230] The method (810) also comprises filling (816) bulk containers at the
wellsite. For
example, the bulk containers may include one or more of the containers 110,
120, 130, 140, and
filling (816) the containers may include operating one or more of the transfer
mechanisms 162,
172, 182, 192 described above.
[00231] The method (810) also comprises communicating (818) materials from one
or more
of the bulk containers to a mixing unit. For example, the mixing unit may be
the mixing unit 200
described above, and communicating (818) materials to the mixing unit 200 may
include
operating one or more of the transfer mechanisms 112, 122, 132, 142 described
above. The
communicating (818) may include splitting an incoming fluid medium, such as
from the one or
more inlets 218, into at least two sub-systems of the mixing unit, such as the
rheology control
portion 202 and the high-volume solids blending portion 210 of the mixing unit
200.
[00232] The method (810) also comprises operating (819) a first sub-system of
the mixing
unit. For example, the first sub-system may be the solids dispersing and/or
mixing system 214
and/or other component of the rheology control portion 202 of the mixing unit
200. Such
operation (819) may, for example, create a substantially continuous stream or
other quantity of a
gel, such as the concentrated first fluid mixture described above. Operating
(819) the first sub-
system may include performing a rheology modifying process that may result in
a fluid mixture
having a higher concentration of certain compositional components (e.g., guar
or other
hydratable material) than the final downhole concentration intended to be
utilized.
[00233] The method (810) also comprises operating (824) a second sub-system of
the mixing
unit. An input to the second sub-system may include the discharge from the
first sub-system.
For example, the second sub-system may be one or more of the solids blending
systems 265
and/or other component of the high-volume solids blending portion 210 of the
mixing unit 200.
Such operation (824) may, for example, create a substantially continuous
stream or other
quantity of a fracturing fluid, such as the second fluid mixture described
above. Operating (824)
the second sub-system may include feeding the discharge from the operation
(819) of the first
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sub-system to the second sub-system where a second set of rheology modifying
solids may be
metered in using conventional methods and/or high-volume solids (e.g.,
proppant and/or other
particulate materials) may be introduced by gravity feed from silos or other
containers, such as
the bulk containers 130 and/or 140.
[00234] The method (810) also comprises discharging (826) fluid from the
second sub-system
of the mixing unit. For example, such discharge (826) may comprise one or more
substantially
continuous streams or other quantities of a fracturing fluid and/or other
fluid mixtures through
one or more outlets 275 of the mixing unit 200.
[00235] The method (810) may also comprise operating (820) a diluter to dilute
the
concentration of the fluid discharged from the first subs-system. However,
operating (820) the
diluter may form part of the operation (819) of the first sub-system. The
diluter may be the
diluter 230 described above. Operating (820) the diluter may include a process
of diluting, on
the fly, a rheology-modified fluid obtained by operating (819) the first sub-
system, to obtain a
fluid near final concentration.
[00236] The method (810) may also comprise introducing (822) one or more
property
enhancing chemicals into the input materials or discharge fluids of operating
(819) the first sub-
system and/or operating (824) the second sub-system. For example, such
introduction (822) may
be via operation of the liquid metering systems 208 described above.
[00237] FIG. 19 is a flow-chart diagram of at least a portion of an example
implementation of
a method (1000) according to one or more aspects of the present disclosure.
The method (1000)
may be performed utilizing at least a portion of one or more implementations
of the apparatus
shown in one or more of FIGS. 1-17 and/or other apparatus within the scope of
the present
disclosure. One or more aspects of implementations of the method (1000) shown
in FIG. 19 may
be substantially similar to one or more aspects of implementations of the
method (810) shown in
FIG. 18. One or more aspects of the method (810) shown in FIG. 18 may be
substantially the
same as corresponding aspects of the method (1000) shown in FIG. 19. One or
more aspects of
the method (810) shown in FIG. 18 may be combined with one or more aspects of
the method
(1000) shown in FIG. 19 in various additional methods within the scope of the
present
disclosure.
[00238] The method (1000) comprises transporting (1005) a mobile system over
ground to a
wellsite. The mobile system may be or comprise the mobile mixing unit 200
shown in FIG. 17,
and/or other systems within the scope of the present disclosure. The method
(1000) may further
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comprise coupling (1002) the mobile system with the prime mover 701 prior to
moving (1005)
the mobile system to the wellsite.
[00239] After moving (1005) the mobile system to the wellsite, the first mixer
214 is operated
(1010) to mix hydratable material and hydrating fluid to form a first fluid
communicated through
one or more instances of the first container 220 and/or the buffer tank 260.
The first fluid may
be the concentrated first fluid mixture or the diluted first fluid mixture
described above. The
second mixer 265 is also operated (1015) to mix particulate material and the
first fluid
discharged from the containers 220 and/or the buffer tank 260 to form a second
fluid at least
partially forming a subterranean formation fracturing fluid. The second fluid
may be the second
fluid mixture described above.
[00240] As described above, operating (1010) the first mixer 214 may comprise
operating the
first mixer 214 to mix substantially continuous supplies of the hydratable
material and the
hydrating fluid to form a substantially continuous supply of the first fluid.
The substantially
continuous supply of the first fluid may be substantially continuously
conveyed from the first
mixer 214 to the second mixer 265 through the containers 220 and/or the buffer
tank 260.
Operating (1015) the second mixer 265 may comprise operating the second mixer
265 to mix a
substantially continuous supply of the particulate material with the
substantially continuous
supply of the first fluid discharged from the containers 220 and/or the buffer
tank 260 to form a
substantially continuous supply of the second fluid.
[00241] The method (1000) may further comprise controlling (1020) a flow rate
of the first
fluid from the containers 220 and/or the buffer tank 260 to the second mixer
265. Controlling
(1020) the flow rate of the first fluid may comprise controlling the pump 241
and/or another
pump in fluid communication between the second mixer 265 and one or more of
the containers
220 and/or the buffer tank 260.
[00242] The method (1000) may further comprise reducing (1025) a concentration
of the
hydratable material in the first fluid received by the second mixer 265. Such
reduction (1025)
may comprise operating the pump 240 to add aqueous fluid to the first fluid
discharged from the
first container(s) 220, operating the pump 240 to adjust a flow rate of the
aqueous fluid added to
the first fluid, operating the valve 250 to adjust the flow rate of the
aqueous fluid added to the
first fluid, operating the pump 241 to adjust a flow rate of the first fluid
from the containers 220
and/or the buffer tank 260 to the second mixer 265, operating the valve 245 to
adjust the flow
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rate of the first fluid from the containers 220 and/or the buffer tank 260 to
the second mixer 265,
or a combination thereof.
[00243] FIG. 20 is a flow-chart diagram of at least a portion of an example
implementation of
a method (830) according to one or more aspects of the present disclosure. The
method (830)
may be performed utilizing at least a portion of one or more implementations
of the apparatus
shown in one or more of FIGS. 1-17 and/or other apparatus within the scope of
the present
disclosure.
[00244] The method (830) comprises transporting (832) equipment to a wellsite.
For
example, the transported (832) equipment may include the support structure 760
shown in FIG.
14, the mobile transfer unit 720 shown in FIGS. 15 and 16, the bulk containers
130, 140 shown
in FIG. 16, the mobile mixing unit 200 shown in FIG. 17, and other equipment
shown in FIG. 1
and/or 13.
[00245] The method (830) also comprises deploying (834) a mobile foundation
base at the
wellsite. For example, the mobile foundation base may be the support structure
760 shown in
FIG. 14.
[00246] The method (830) also comprises erecting (836) silos and/or other
vertical bulk
containers on the deployed (834) mobile foundation base. For example, the
erected (836)
containers may be the bulk containers 130, 140 shown in FIG. 16. Erecting
(836) the containers
may also include aligning the containers with the mobile foundation base, such
as via the
alignment features described above with respect to the support structure 760
shown in FIG. 14.
[00247] The method (830) also comprises deploying (838) a transfer/loading
system with
respect to the deployed (834) mobile foundation base and the erected (836)
bulk containers. For
example, the transfer/loading system may be the mobile transfer unit 720 shown
in FIGS. 15 and
16. Deploying (838) the transfer/loading system may also include aligning the
transfer/loading
system with the mobile foundation base, such as via the alignment features
described above with
respect to the support structure 760 shown in FIG. 14.
[00248] The method (830) also comprises driving (840) a mixing unit under the
deployed
(834) mobile foundation base such that receipt/storage portions of the mobile
mixing unit align
with respect to discharge locations of the erected (836) bulk containers. The
mobile mixing unit
may be the mobile mixing unit 200 shown in FIG. 17, such that driving (840)
the mixing unit
may entail operating the prime mover 701. Driving (840) the mixing unit under
the deployed
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(834) mobile foundation base may be performed before, during, or after
erecting (836) the bulk
containers and/or deploying (838) the transfer/loading system.
[00249] The method (830) also comprises connecting (842) other material supply
systems to
the mixing unit via the various transfer mechanisms described above. Such
connection (842)
may include connecting the transfer mechanism 112 between the bulk container
110 and the
mixing unit 200, connecting the transfer mechanism 122 between the bulk
container 120 and the
mixing unit 200, connecting the transfer mechanism 132 between the bulk
container 130 and the
mixing unit 200, and/or connecting the transfer mechanism 142 between the bulk
container 140
and the mixing unit 200, unless the bulk containers were among those
previously erected (836).
[00250] The method (830) also comprises connecting (844) a power source to the
mixing unit.
For example, the power source may be the centralized power source 195
described above.
[00251] The method (830) also comprises loading (846) buffer storage volumes
on the mixing
unit using the associated transfer mechanisms. For example, such loading (846)
may include
loading the solids receiving and/or storage means 204, solids receiving and/or
storage means
280, and/or the high-volume solids receiving and/or storage means 266
described above.
[00252] FIG. 21 is a flow-chart diagram of at least a portion of an example
implementation of
a method (900) according to one or more aspects of the present disclosure. The
method (900)
may be performed utilizing at least a portion of one or more implementations
of the apparatus
shown in one or more of FIGS. 1-17 and/or other apparatus within the scope of
the present
disclosure. One or more aspects of implementations of the method (900) shown
in FIG. 21 may
be substantially similar to one or more aspects of implementations of the
method (830) shown in
FIG. 20. One or more aspects of the method (830) shown in FIG. 20 may be
substantially the
same as corresponding aspects of the method (900) shown in FIG. 21. One or
more aspects of
the method (830) shown in FIG. 20 may be combined with one or more aspects of
the method
(900) shown in FIG. 21 in various additional methods within the scope of the
present disclosure.
[00253] The method (900) comprises operating (905) one or more of the transfer
mechanisms
162, 172, 182, 192 to transfer materials received from corresponding delivery
vehicles 160, 170,
180, 190 to the corresponding bulk containers 110, 120, 130, 140. One or more
of the transfer
mechanisms 112, 122, 132, 142 are also operated (910) to transfer
corresponding materials from
the corresponding bulk containers 110, 120, 130, 140 to the mixing unit 200.
The mixing unit
200 is operated (915) to at least partially form a subterranean formation
fracturing fluid utilizing
each of the materials received from the transfer mechanisms 112, 122, 132,
142. Operating
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(910) the transfer mechanisms 112, 122, 132, 142 to transfer the materials
from the bulk
containers 110, 120, 130, 140 to the mixing unit 200 may comprise operating
each of the transfer
mechanisms 112, 122, 132, 142 while not operating at least one of the transfer
mechanisms 162,
172, 182, 192. The method (900) may further comprise physically aligning (920)
each of the
delivery vehicles 160, 170, 180, 190 with the corresponding transfer
mechanisms 162, 172, 182,
192.
[00254] Operating (915) the mixing unit 200 to at least partially form the
subterranean
formation fracturing fluid utilizing each of the materials received from each
of the transfer
mechanisms 112, 122, 132, 142 may comprise substantially continuously
operating the mixing
unit 200 to form a substantially continuous supply at least partially foiming
the subterranean
formation fracturing fluid when not operating at least one of the transfer
mechanisms 162, 172,
182, 192.
[00255] FIG. 22 is a flow-chart diagram of at least a portion of an example
implementation of
a method (930) according to one or more aspects of the present disclosure. The
method (930)
may be performed utilizing at least a portion of one or more implementations
of the apparatus
shown in one or more of FIGS. 1-17 and/or other apparatus within the scope of
the present
disclosure.
[00256] The method (930) comprises operating (935) the controller 510 of the
mixing unit
200 to enter a hydratable material concentration setpoint of a first fluid.
The first fluid may be
the concentrated first fluid mixture or the diluted first fluid mixture
described above, such as may
be discharged by the first mixer 214, the first container(s) 220, the diluter
230, or the second
container 260. The controller 510 is also operated (940) to enter a proppant
material
concentration setpoint of a second fluid at least partially forming a
subterranean formation
fracturing fluid. The second fluid may be the second fluid mixture described
above, such as may
be discharged by the second mixer 265 or the mixing unit 200 as a whole. The
controller 510 is
then operated (945) to commence operation of the mixing unit 200 to form a
substantially
continuous supply of the second fluid having the proppant material
concentration.
[00257] Operating (945) the controller 510 to commence operation of the mixing
unit 200
may cause the controller 510 to control a rate at which the hydratable
material transfer device
206 and/or another metering device meters the hydratable material into the
first mixer 214 based
on the hydratable material concentration setpoint. Operating (945) the
controller 510 to
commence operation of the mixing unit 200 may also or instead cause the
controller 510 to
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control a rate at which 281 the particulate material metering device 267
and/or another metering
device meters the proppant material into the second mixer 265 based on the
proppant material
concentration setpoint.
[00258] The method (930) may further comprise operating (950) the controller
510 to enter a
diluted hydratable material concentration setpoint. In such implementations,
operating (945) the
controller 510 to commence operation of the mixing unit 200 may cause the
controller 510 to,
based on the diluted hydratable material concentration setpoint, control
corresponding flow
control devices to control a flow rate of the first fluid to the second mixer
265, to form the first
fluid having the diluted hydratable material concentration, and/or to control
a flow rate of a
diluting fluid that is combined with the first fluid before the first fluid is
received by the second
mixer 265, to form the first fluid having the diluted hydratable material
concentration.
[00259] The method (930) may further comprise operating (955) the controller
510 to enter a
liquid additive concentration setpoint of the second fluid. In such
implementations, operating
(945) the controller 510 to commence operation of the mixing unit 200 may
cause the controller
510 to, based on the liquid additive concentration setpoint, control a rate at
which a liquid
additive is added to one of the first and second fluids to form the first or
second fluid having the
liquid additive concentration.
[00260] The method (930) may further comprise operating (960) the controller
510 to enter a
solid additive concentration setpoint of the second fluid. In such
implementations, operating
(945) the controller 510 to commence operation of the mixing unit 200 may
cause the controller
510 to, based on the solid additive concentration setpoint, control a rate at
which a metering
device meters a solid additive into the second mixer 265 to form the second
fluid having the
solid additive concentration.
[00261] Operating (945) the controller 510 to commence operation of the mixing
unit 200
may also cause the controller 510 to control the various flow control devices
to control the flow
of the hydrating fluid, the first fluid, and the second fluid based on at
least one of the hydrating
material concentration setpoint and the proppant material concentration
setpoint. Operating
(945) the controller 510 to commence operation of the mixing unit 200 may also
cause the
controller 510 to control the various metering devices to meter the hydratable
material and the
proppant material based on at least one of the hydrating material
concentration setpoint and the
proppant material concentration setpoint. As also described above, the mixing
unit 200 may
comprise various sensors in communication with the controller 510 and operable
to generate
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information related to flow rates of the hydrating fluid, the hydratable
material, the first fluid, the
proppant material, and the second fluid. In such implementations, the
controller 510 may be
operable to control the various flow control and metering devices based on the
generated
information.
[00262] In view of the entirety of the present disclosure, including the
claims and the figures,
a person having ordinary skill in the art should readily recognize that the
present disclosure
introduces an apparatus comprising: a mobile system comprising: a frame; a
plurality of wheels
operatively connected with and supporting the frame on the ground; a first
mixer connected with
the frame and operable to receive and mix hydratable material and hydrating
fluid to form a first
fluid; a container connected with the frame and comprising a flowpath
traversed by the first fluid
for a period of time sufficient to permit viscosity of the first fluid to
increase to a predetermined
level; and a second mixer connected with the frame and operable to mix
particulate material and
the first fluid discharged from the container to form a second fluid at least
partially forming a
subterranean formation fracturing fluid.
[00263] The first mixer may be operable to substantially continuously form the
first fluid, the
container may be operable to substantially continuously convey the first fluid
between the first
and second mixers, and the second mixer may be operable to substantially
continuously form the
second fluid.
[00264] The first mixer may be operable to: receive a substantially continuous
supply of the
hydratable material; receive a substantially continuous supply of the
hydrating fluid; and
substantially continuously mix the substantially continuous supply of the
hydratable material and
the substantially continuous supply of the hydrating fluid to form a
substantially continuous
supply of the first fluid. In such implementations, the substantially
continuous supply of the first
fluid may be substantially continuously conducted through the flowpath of the
container; and the
second mixer may be operable to: receive a substantially continuous supply of
the particulate
material; receive the substantially continuous supply of the first fluid from
the container; and
substantially continuously mix the substantially continuous supply of the
particulate material and
the substantially continuous supply of the first fluid discharged from the
container to form a
substantially continuous supply of the second fluid.
[00265] The mobile system may further comprise a fluid junction between the
container and
the second mixer and operable to add aqueous fluid to the first fluid
discharged from the
container. The fluid junction may comprise: a first passage operable to
receive the aqueous
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fluid; a second fluid passage operable to receive the first fluid discharged
from the container; and
a third passage operable to communicate both the aqueous fluid and the first
fluid discharged
from the container. The hydrating fluid and the aqueous fluid may be the same
and may be
received by the first mixer and the fluid junction from a single source. The
mobile system may
further comprise at least one of: a first flow control device operable to
control a first flow rate of
the first fluid discharged from the container to the fluid junction; and a
second flow control
device operable to control a second flow rate of the aqueous fluid to the
fluid junction. At least
one of the first and second flow control devices may comprise a flow control
valve. At least one
of the first and second flow control devices may comprise a pump.
[00266] The container may be a first container, the mobile system may further
comprise a
second container fluidly coupled between the first container and the second
mixer, the second
container may receive the first fluid discharged from the first container, and
the second mixer
may be operable to receive the first fluid from the second container.
[00267] The hydratable material may substantially comprise guar. The
hydratable material
may substantially comprise a polymer, a synthetic polymer, a galactomannan, a
polysaccharide, a
cellulose, a clay, or a combination thereof. The hydrating fluid may
substantially comprise
water. The particulate material may comprise a proppant material. The proppant
material may
comprise one or more of sand, sand-like particles, silica, and quartz. The
particulate material
may further comprise a fibrous material. The fibrous material may comprise one
or more of
fiberglass, phenol formaldehyde, polyester, polylactic acid, cedar bark,
shredded cane stalks,
mineral fiber, and hair.
[00268] The container may be a first-in-first-out continuous fluid container.
[00269] The mobile system may be operable for connection with a prime mover.
[00270] The present disclosure also introduces a method comprising: moving a
mobile system
over ground to a wellsite, wherein the mobile system comprises: a frame; a
plurality of wheels
operatively connected with and supporting the frame on the ground; a first
mixer connected with
the frame; a container connected with the frame and in fluid communication
with the first mixer;
and a second mixer connected with the frame and in fluid communication with
the container;
operating the first mixer to mix hydratable material and hydrating fluid to
form a first fluid
communicated through the container; and operating the second mixer to mix
particulate material
and the first fluid discharged from the container to form a second fluid at
least partially forming
a subterranean formation fracturing fluid.
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[00271] Operating the first mixer may comprise operating the first mixer to
mix substantially
continuous supplies of the hydratable material and the hydrating fluid to form
a substantially
continuous supply of the first fluid. The substantially continuous supply of
the first fluid may be
substantially continuously conveyed from the first mixer to the second mixer
through the
container. Operating the second mixer may comprise operating the second mixer
to mix a
substantially continuous supply of the particulate material with the
substantially continuous
supply of the first fluid discharged from the container to form a
substantially continuous supply
of the second fluid.
[00272] The container may internally conduct the first fluid for a period of
time sufficient to
permit viscosity of the first fluid to increase to a predetermined level.
[00273] Operating the first mixer may sufficiently pressurize the first fluid
to cause the first
fluid to be communicated through the container.
[00274] The method may further comprise controlling a flow rate of the first
fluid from the
container to the second mixer. Controlling the flow rate of the first fluid
may comprise
controlling a pump in fluid communication between the container and the second
mixer.
[00275] The mobile system may further comprise a pump, and the method may
further
comprise operating the pump to add aqueous fluid to the first fluid discharged
from the container
to reduce a concentration of the hydratable material in the first fluid
received by the second
mixer. The pump may be a first pump, and the method may further comprise at
least one of:
operating the first pump to adjust a first flow rate of the aqueous fluid
added to the first fluid;
operating a first valve downstream of the first pump to adjust the first flow
rate; operating a
second pump in fluid communication between the container and the second mixer
to adjust a
second flow rate of the first fluid from the container to the second mixer;
and operating a second
valve downstream of the second pump to adjust the second flow rate.
[00276] The container may be a first container, the mobile system may further
comprise a
second container in fluid communication between the container and the second
mixer, operating
the first mixer to form the first fluid communicated through the first
container may communicate
the first fluid through the first container to the second container, and the
first fluid mixed with
the particulate material by the second mixer may be obtained from the second
container. In such
implementations, the mobile system may further comprise a pump, and the method
may further
comprise operating the pump to add aqueous fluid to the first fluid discharged
from the first
container and received by the second container.
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[00277] The method may further comprise coupling the mobile system with a
prime mover.
[00278] The present disclosure also introduces an apparatus comprising: a
wellsite system for
utilization in a subterranean fracturing operation, wherein the wellsite
system comprises: a
plurality of containers; a plurality of first transfer mechanisms each
operable to transfer a
corresponding one of a plurality of materials from a corresponding one of a
plurality of delivery
vehicles to a corresponding one of the containers; a mixing unit; and a
plurality of second
transfer mechanisms each operable to transfer a corresponding one of the
materials from a
corresponding one of the containers to the mixing unit, wherein the mixing
unit is operable to
mix the materials received from each of the second transfer mechanisms to form
a subterranean
formation fracturing fluid.
[00279] The plurality of materials may comprise hydratable material, liquid
additives, solid
additives, and proppant material, and the plurality of first transfer
mechanisms may comprise: a
hydratable material transfer mechanism operable to transfer the hydratable
material to a first one
of the containers; a liquid additive transfer mechanism operable to transfer
the liquid additives to
a second one of the containers; a solid additive transfer mechanism operable
to transfer the solid
additives to a third one of the containers; and a proppant material transfer
mechanism operable to
transfer the proppant material to a fourth one of the containers. In such
implementations, the
plurality of second transfer mechanisms may comprise: an additional hydratable
material transfer
mechanism operable to transfer the hydratable material from the first one of
the containers to the
mixing unit; an additional liquid additive transfer mechanism operable to
transfer the liquid
additives from the second one of the containers to the mixing unit; an
additional solid additive
transfer mechanism operable to transfer the solid additives from the third one
of the containers to
the mixing unit; and an additional proppant material transfer mechanism
operable to transfer the
proppant material from the fourth one of the containers to the mixing unit.
[00280] The wellsite system may further comprise a material delivery area
adjacent the first
transfer mechanisms, and the containers may each be physically located between
the mixing unit
and the material delivery area.
[00281] Each of the containers may be operable to receive therein an entire
quantity of the
corresponding material transported by the corresponding delivery vehicle.
[00282] Each of the containers may have a storage capacity that is about equal
to or greater
than a storage capacity of the corresponding delivery vehicle.
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[00283] The first transfer mechanisms may be operable to periodically transfer
the
corresponding materials from the delivery vehicles to the corresponding
containers, the second
transfer mechanisms may be operable to substantially continuously transfer the
corresponding
materials from the corresponding containers to the mixing unit, and the mixing
unit may be
operable to discharge a substantially continuous supply of the fracturing
fluid.
[00284] The mixing unit may be operable to substantially continuously form the
fracturing
fluid when one or more of the first transfer mechanisms is not transferring
the corresponding one
or more of the materials from the corresponding one or more delivery vehicles.
[00285] The mixing unit may comprise a mixer and a hopper associated with the
mixer, and
one of the second transfer mechanisms may be operable to transfer a
corresponding one of the
materials from a corresponding one of the containers into the hopper.
[00286] The plurality of materials may comprise hydratable material and
proppant material,
the mixing unit may comprise a first mixer and a second mixer, and the
plurality of second
transfer mechanisms may comprise: a hydratable material transfer mechanism
operable to
transfer the hydratable material to a first hopper operable to feed the
hydratable material to the
first mixer; and a proppant material transfer mechanism operable to transfer
the proppant
material to a second hopper operable to feed the proppant material to the
second mixer.
[00287] The plurality of materials may comprise hydratable material and
proppant material,
and the mixing unit may comprise: a frame; a first mixer connected with the
frame and operable
to mix the hydratable material with a hydrating fluid to form a mixture; and a
second mixer
connected with the frame and operable to mix the proppant material with the
mixture. The
mixing unit may further comprise a plurality of wheels operatively connected
with and
supporting the frame on the ground. The mixing unit may further comprise a
hydrating container
connected with the frame and in fluid communication between the first and
second mixers.
[00288] The present disclosure also introduces a method comprising: operating
each of a
plurality of first transfer mechanisms to transfer a corresponding one of a
plurality of materials
received from a corresponding one of a plurality of delivery vehicles to a
corresponding one of a
plurality of containers, wherein each of the plurality of materials has a
different composition;
operating each of a plurality of second transfer mechanisms to transfer a
corresponding one of
the plurality of materials from a corresponding one of the plurality of
containers to a mixing unit;
and operating the mixing unit to at least partially form a subterranean
formation fracturing fluid
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utilizing each of the plurality of materials received from each of the
plurality of second transfer
mechanisms.
[00289] Operating each of the plurality of second transfer mechanisms to
transfer a
corresponding one of the plurality of materials from a corresponding one of
the plurality of
containers to the mixing unit may comprise operating each of the plurality of
second transfer
mechanisms while not operating at least one of the plurality of first transfer
mechanisms.
[00290] The method may further comprise physically aligning each of the
plurality of delivery
vehicles with the corresponding one of the plurality of first transfer
mechanisms, such as within a
contiguous physical area simultaneously accessible by the plurality of
delivery vehicles.
[00291] The method may further comprise storing an amount of each of the
plurality of
materials in each corresponding one of the plurality of containers, wherein
the amount of each of
the plurality of materials stored in each corresponding one of the plurality
of containers may be
about equal to or greater than a storage capacity of the corresponding one of
the plurality of
delivery vehicles.
[00292] Operating each of the plurality of first transfer mechanisms to
transfer the
corresponding one of the plurality of materials to the corresponding one of
the plurality of
containers may comprise periodically operating each of the plurality of first
transfer mechanisms
to periodically transfer the corresponding one of the plurality of materials
to the corresponding
one of the plurality of containers. In such implementations, operating each of
the plurality of
second transfer mechanisms to transfer the corresponding one of the plurality
of materials from
the corresponding one of the plurality of containers to the mixing unit may
comprise
substantially continuously operating each of the plurality of second transfer
mechanisms to
substantially continuously transfer the corresponding one of the plurality of
materials from the
corresponding one of the plurality of containers to the mixing unit, and
operating the mixing unit
to at least partially form the subterranean formation fracturing fluid
utilizing each of the plurality
of materials received from each of the plurality of second transfer mechanisms
may comprise
substantially continuously operating the mixing unit to form a substantially
continuous supply at
least partially forming the subterranean formation fracturing fluid.
[00293] Operating the mixing unit to at least partially form the subterranean
formation
fracturing fluid utilizing each of the plurality of materials received from
each of the plurality of
second transfer mechanisms may comprise substantially continuously operating
the mixing unit
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to form a substantially continuous supply at least partially forming the
subterranean formation
fracturing fluid when not operating at least one of the plurality of first
transfer mechanisms.
[00294] The plurality of second transfer mechanisms may comprise a hydratable
material
transfer mechanism and a proppant material transfer mechanism, and operating
the mixing unit
to at least partially form the subterranean formation fracturing fluid may
comprise: operating a
first mixer of the mixing unit to form a mixture comprising hydratable
material received from the
hydratable material transfer mechanism, wherein the first mixer is connected
with a frame; and
operating a second mixer of the mixing unit to combine the mixture with
proppant material
received from the proppant material transfer mechanism, wherein the second
mixer is connected
with the frame. The second mixer may receive the mixture discharged by the
first mixer via a
hydrator fluidly connected between the first and second mixers, wherein the
hydrator is
connected with the frame.
[00295] Operating each of the plurality of second transfer mechanisms to
transfer the
corresponding one of the plurality of materials from the corresponding one of
the plurality of
containers to the mixing unit may comprise operating at least one of the
plurality of second
transfer mechanisms to transfer the corresponding one of the plurality of
materials from the
corresponding one of the plurality of containers to a hopper of the mixing
unit.
[00296] The plurality of materials may comprise a hydratable material and a
proppant
material. The plurality of materials may comprise a hydratable material, a
proppant material, a
liquid additive, and a solid additive.
[00297] The present disclosure also introduces an apparatus comprising: a
first mixer operable
to form a mixture by combining hydratable material and hydrating fluid; a
second mixer operable
to at least partially form a subterranean formation fracturing fluid by
combining the mixture and
proppant material; and a controller operable to control: a hydratable material
concentration of the
mixture; and a proppant material concentration of the subterranean formation
fracturing fluid.
[00298] The controller may be further operable to control a discharge flow
rate of the second
mixer.
[00299] The apparatus may further comprise a frame to which the first and
second mixers are
connected. The apparatus may further comprise a control center comprising the
controller and
connected to the frame. The apparatus may further comprise a hydrator
connected to the frame,
wherein the mixture may be received by the second mixer via the hydrator.
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[00300] The apparatus may further comprise: a plurality of flow meters in
communication
with the controller and operable to generate information related to
corresponding flow rates of
the hydrating fluid, the mixture, and the subterranean formation fracturing
fluid; a plurality of
flow control devices in communication with the controller, wherein the
controller may be further
operable to control the plurality of flow control devices to control the flow
rates of the hydrating
fluid, the mixture, and the subterranean formation fracturing fluid; and a
plurality of metering
devices in communication with the controller, wherein the controller may be
further operable to
control the plurality of metering devices to meter the hydratable material and
the proppant
material. The controller may be further operable to automatically control the
plurality of flow
control devices and the plurality of metering devices based on predetermined
setpoints for the
hydratable material concentration and the proppant material concentration. The
controller may
be further operable to receive user inputs, wherein the user inputs comprise
the predetermined
setpoints for the hydratable material concentration and the proppant material
concentration.
[00301] The apparatus may further comprise: a flow control device in
communication with the
controller, wherein the controller may be further operable to control the flow
control device to
control the flow of the hydrating fluid into the first mixer; a flow meter in
communication with
the controller and operable to generate information related to flow of the
hydrating fluid into the
first mixer; and a metering device in communication with the controller,
wherein controller may
be further operable to control the metering device to meter the hydratable
material into the first
mixer and, thereby, control the hydratable material concentration of the
mixture discharged by
the first mixer.
[00302] The apparatus may further comprise: a diluter operable to dilute the
mixture
discharged by the first mixer before the mixture is received by the second
mixer; at least one
flow meter in communication with the controller and operable to generate
information related to
flow of at least one of the mixture discharged by the first mixer and a
diluting fluid added to the
mixture by the diluter; and at least one flow control device in communication
with the controller
and operable to control the flow of the at least one of the mixture discharged
by the first mixer
and the diluting fluid added to the mixture by the diluter, wherein the
controller may be further
operable to control the at least one flow control device to control the
hydratable material
concentration of the diluted mixture discharged by the diluter.
[00303] The apparatus may further comprise: a tank for storing the mixture
discharged from
the first mixer, wherein the second mixer may be operable to receive the
mixture from the tank;
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and a level sensor in communication with the controller and operable to
generate information
related to the quantity of the mixture within the tank.
[00304] The apparatus may further comprise: a flow control device in
communication with the
controller, wherein controller may be further operable to control the flow
control device to
control the flow of the mixture into the second mixer; a flow meter in
communication with the
controller and operable to generate information related to the flow of the
mixture into the second
mixer; and a metering device in communication with the controller, wherein the
controller may
be further operable to control the metering device to meter the proppant
material into the second
mixer and, thereby, control the proppant material concentration of the
subterranean formation
fracturing fluid.
[00305] The apparatus may further comprise a liquid additive injection conduit
fluidly
connected with a liquid additive source for introducing a liquid additive into
at least one of: the
mixture received by the second mixer from the first mixer; and the fracturing
fluid discharged
from the second mixer. The apparatus may further comprise: at least one flow
meter in
communication with the controller and operable to generate information related
to flow of the
liquid additive through the liquid additive injection conduit; and at least
one flow control device
in communication with the controller and operable to control the flow of the
liquid additive
through the liquid additive injection conduit, wherein the controller may be
further operable to
control the at least one flow control device to control the flow of the liquid
additive through the
liquid additive injection conduit.
[00306] The apparatus may further comprise: a solid additive transfer
mechanism for
introducing a solid additive into at least one of: the mixture received by the
second mixer from
the first mixer; and the fracturing fluid discharged from the second mixer.
The apparatus may
further comprise at least one flow control device in communication with the
controller and
operable to control the rate of the introduced solid additive, wherein the
controller may be further
operable to control the at least one flow control device to control the rate
of the introduced solid
additive.
[00307] The apparatus may further comprise: a plurality of flow control
devices in
communication with the controller, wherein the controller may be further
operable to control the
plurality of flow control devices to control the flow of the hydrating fluid,
the mixture, and the
subterranean fonnation fracturing fluid; and a plurality of metering devices
in communication
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with the controller, wherein the controller may be further operable to control
the plurality of
metering devices to meter the hydratable material and the proppant material.
[00308] The apparatus may further comprise: a plurality of flow control
devices in
communication with the controller and operable to control the flow of the
hydrating fluid, the
mixture, and the subterranean formation fracturing fluid; and a plurality of
metering devices in
communication with the controller and operable to meter the hydratable
material and the
proppant material; wherein the controller may be operable to control the
hydratable material
concentration of the mixture and the proppant material concentration of the
subterranean
formation fracturing fluid by controlling the plurality of flow control
devices, the plurality of
metering devices, and the first and second mixers.
[00309] The present disclosure also introduces a method comprising: operating
a controller of
a system to enter a hydratable material concentration setpoint of a first
fluid, wherein the system
comprises the controller and a first mixer, and wherein the first mixer is
operable to mix
hydratable material and hydrating fluid to form the first fluid having the
hydratable material
concentration; operating the controller to enter a proppant material
concentration setpoint of a
second fluid at least partially forming a subterranean formation fracturing
fluid, wherein the
system further comprises a second mixer operable to mix proppant material and
the first fluid to
form the second fluid having the proppant material concentration; and
operating the controller to
commence operation of the system to form a substantially continuous supply of
the second fluid
having the proppant material concentration.
[00310] Operating the controller to commence operation of the system may cause
the
controller to control a rate at which a metering device meters the hydratable
material into the first
mixer based on the hydratable material concentration setpoint.
[00311] Operating the controller to commence operation of the system may cause
the
controller to control a rate at which a metering device meters the proppant
material into the
second mixer based on the proppant material concentration setpoint.
[00312] The method may further comprise operating the controller to enter a
diluted
hydratable material concentration setpoint, wherein operating the controller
to commence
operation of the system may cause the controller to control, based on the
diluted hydratable
material concentration setpoint, a rate at which: a first flow control device
controls a first flow
rate of the first fluid to the second mixer to form the first fluid having the
diluted hydratable
material concentration; a second flow control device controls a second flow
rate of a diluting
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fluid combined with the first fluid before the first fluid is received by the
second mixer to form
the first fluid having the diluted hydratable material concentration; or a
combination thereof.
[00313] The method may further comprise operating the controller to enter a
liquid additive
concentration setpoint of the second fluid, wherein operating the controller
to commence
operation of the system may cause the controller to control, based on the
liquid additive
concentration setpoint, a rate at which a liquid additive is added to one of
the first and second
fluids to form the first or second fluid having the liquid additive
concentration.
[00314] The method may further comprise operating the controller to enter a
solid additive
concentration setpoint of the second fluid, wherein operating the controller
to commence
operation of the system may cause the controller to control, based on the
solid additive
concentration setpoint, a rate at which a metering device meters a solid
additive into the second
mixer to form the second fluid having the solid additive concentration.
[00315] The system may further comprise a plurality of flow control devices in
communication with the controller and a plurality of metering devices in
communication with
the controller, wherein operating the controller to commence operation of the
system may cause
the controller to control: the plurality of flow control devices to control
the flow of the hydrating
fluid, the first fluid, and the second fluid based on at least one of the
hydrating material
concentration setpoint and the proppant material concentration setpoint; and
the plurality of
metering devices to meter the hydratable material and the proppant material
based on at least one
of the hydrating material concentration setpoint and the proppant material
concentration setpoint.
The system may further comprise a plurality of sensors in communication with
the controller and
operable to generate information related to flow rates of the hydrating fluid,
the hydratable
material, the first fluid, the proppant material, and the second fluid, and
the controller may be
operable to control the plurality of flow control devices and the plurality of
metering devices
based on the generated information.
1003161 The present disclosure also introduces an apparatus comprising: a
mobile system
comprising: a frame; a plurality of wheels operatively connected with and
supporting the frame
on the ground; a first mixer connected with the frame and operable to receive
and mix a
hydratable material and a hydrating fluid to form a first fluid; a container
connected with the
frame and comprising a substantially continuous passageway traversed by a
second fluid for a
period of time sufficient to permit viscosity of the second fluid to increase
to a predetermined
level, wherein the second fluid comprises the first fluid; and a second mixer
connected with the
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frame and operable to mix particulate material with a third fluid to form a
fourth fluid utilized in
a subterranean formation fracturing operation, wherein the third fluid
comprises the second fluid
discharged from the container.
[00317] The foregoing outlines features of several implementations so that a
person having
ordinary skill in the art may better understand the aspects of the present
disclosure. A person
having ordinary skill in the art should appreciate that they may readily use
the present disclosure
as a basis for designing or modifying other processes and structures for
carrying out the same
functions and/or achieving the same benefits of the implementations introduced
herein. A person
having ordinary skill in the art should also realize that such equivalent
constructions do not
depart from the spirit and scope of the present disclosure, and that they may
make various
changes, substitutions and alterations herein without departing from the
spirit and scope of the
present disclosure.
[00318] The Abstract at the end of this disclosure is provided to comply with
37 C.F.R.
1.72(b) to permit the reader to quickly ascertain the nature of the technical
disclosure. It is
submitted with the understanding that it will not be used to interpret or
limit the scope or
meaning of the claims.
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