Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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SYSTEMS AND METHODS THAT UTILIZE A DUAL-DUTY
AGENT TO INCREASE VISCOUS HYDROCARBON
PRODUCTION FROM A SUBTERRANEAN FORMATION
FIELD OF THE DISCLOSURE
[0001] The present disclosure is directed generally to systems and
methods for increasing
production of viscous hydrocarbons from a subterranean formation, and more
particularly to
systems and methods that utilize a dual-duty agent to both dilute and increase
the temperature
of the viscous hydrocarbons, thereby decreasing the viscosity of the viscous
hydrocarbons.
BACKGROUND OF THE DISCLOSURE
[0002] Subterranean formations may contain unconventional hydrocarbon
reserves that
may include high-viscosity and/or quasi-solid hydrocarbons, which may be
referred to herein
as viscous hydrocarbons. As an illustrative, non-exclusive example, bitumen
that is present
in oil sands formations may include a viscosity of at least 10,000 centipoise
(cP) under
reservoir conditions. Due to their high viscosity, these viscous hydrocarbons
may be difficult
to pump and/or otherwise produce from the subterranean formation.
[0003] Under certain conditions and/or with certain subterranean
formations, it may be
possible to remove these viscous hydrocarbons from the subterranean formation
using mining
and/or other ex situ processes. However, doing so often requires corresponding
complex
and/or expensive processes, and may yield less than a desired amount of the
viscous
hydrocarbons. For formations that are too deep to be mined using conventional
ex situ
processes, in situ processes_may be used. Accordingly, attempts have been made
to decrease
the viscosity of the viscous hydrocarbons in situ and thereby avoid some of
the disadvantages
of producing viscous hydrocarbons via ex situ processes. This decrease in
viscosity may
permit production of the viscous hydrocarbons through hydrocarbon wells that
may extend
within the subterranean formation.
[0004] A variety of in situ processes has been utilized to decrease the
viscosity of these
viscous hydrocarbons. Generally, these in situ processes fall into two
distinct categories.
The first category includes processes that increase the temperature of the
viscous
hydrocarbons to decrease the viscosity of the viscous hydrocarbons. The second
category
includes processes that dilute the viscous hydrocarbons to decrease the
viscosity of the
1
viscous hydrocarbons. Accordingly, the first category of processes may be
referred to herein
as thermal processes, and the second category of processes may be referred to
herein as
dilution processes.
[0005] While both thermal processes and dilution processes may be utilized to
increase
production of viscous hydrocarbons from certain unconventional hydrocarbon
reserves, both
processes have inherent limitations. Thus, there exists a need for improved
systems and
methods for increasing viscous hydrocarbon production from a subterranean
formation.
SUMMARY OF THE DISCLOSURE
[0006] Systems and methods for enhancing production of viscous
hydrocarbons from a
subterranean formation. The systems and methods include supplying a dual-duty
agent and
an oxidant to the subterranean formation and combusting a portion (which may
be referred to
herein as a combusted portion) of the dual-duty agent with the oxidant to heat
a heated zone
of the subterranean formation. The systems and methods further include flowing
an
uncombusted portion of the dual-duty agent through the heated zone to heat the
uncombusted
portion of the dual-duty agent and generate a heated dual-duty agent. The
systems and
methods also include contacting the viscous hydrocarbons with the heated dual-
duty agent to
generate heated and diluted hydrocarbons that have a lower viscosity than a
viscosity of the
viscous hydrocarbons.
[0007] In some embodiments, the systems and methods further include pre-
heating the
dual-duty agent prior to supplying the dual-duty agent to the subterranean
formation. In
some embodiments, the systems and methods further include producing the heated
and
diluted hydrocarbons from the subterranean formation. In some embodiments, a
single well
conveys the dual-duty agent and the oxidant to the subterranean Ibrmation and
produces the
heated and diluted hydrocarbons from the subterranean formation. In some
embodiments, an
injection well conveys the dual-duty agent and the oxidant to the subterranean
formation, and
a separate production well produces the heated and diluted hydrocarbons from
the
subterranean formation.
[0008] In some embodiments, the systems and methods further include
initiating the
supply of the oxidant to the subterranean formation and/or initiating the
combusting based, at
least in part, on the temperature of the heated zone, the temperature of the
heated and diluted
hydrocarbons, and/or the viscosity of the heated and diluted hydrocarbons. In
some
embodiments, the systems and methods further include ceasing the supplying of
the oxidant
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while continuing the supplying of the dual-duty agent to the subterranean
formation. In some
embodiments, the ceasing may be based, at least in part, on the temperature of
the heated
zone, the temperature of the heated and diluted hydrocarbons, and/or
combustion of a
predetermined fraction of the dual-duty agent.
[0009] In some embodiments, the systems and methods further may include
removing a
portion of the viscous hydrocarbons from the heated zone prior to the
combusting of the dual-
duty agent. In some embodiments, this may include supplying a portion of the
dual-duty
agent to the subterranean formation to produce the diluted hydrocarbons prior
to combusting
a different, or subsequent, portion of the dual-duty agent. In some
embodiments, this may
include performing a cyclic solvent process (CSP), a heated solvent process, a
heated vapour
extraction (VAPEX) process, a non-heated VAPEX process, a steam-assisted
gravity
drainage (SAGD) process, a solvent-assisted steam-assisted gravity drainage
(SA-SAGD)
process, a steamflooding process, and/or an in situ combustion process to
produce the diluted
hydrocarbons prior to the combusting. In some embodiments, this may include
producing a
portion of the diluted hydrocarbons and/or the viscous hydrocarbons from the
subterranean
formation prior to the combusting of the dual-duty agent.
[0009a] Certain exemplary embodiments can provide a method of heating and
diluting
viscous hydrocarbons within a subterranean formation, the method comprising:
supplying a
dual-duty agent comprising a diluent to the subterranean formation; supplying
an oxidant to
the subterranean formation; combusting a combusted portion of the dual-duty
agent with the
oxidant to heat a portion of the subterranean formation, with the portion of
the subterranean
formation forming a heated zone of the subterranean formation; flowing an
uncombusted
portion of the dual-duty agent at least one of through the heated zone and
around the heated
zone, wherein the flowing includes flowing to heat the uncombusted portion of
the dual-duty
agent and generate a heated dual-duty agent; and contacting the viscous
hydrocarbons with
the heated dual-duty agent to generate heated and diluted hydrocarbons which
have a lower
viscosity than the viscous hydrocarbons via dilution with the heated dual-duty
agent.
[0009b] Certain exemplary embodiments can provide a method of heating and
diluting
viscous hydrocarbons within a subterranean formation, the method comprising:
supplying a
dual-duty agent comprising a diluent to the subterranean formation; supplying
an oxidant to
the subterranean formation; combusting a combusted portion of the dual-duty
agent with the
oxidant to heat a portion of the subterranean formation, with this portion of
the subterranean
formation forming a heated zone of the subterranean formation; ceasing the
supplying of the
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oxidant while continuing the supplying of the dual-duty agent to the
subterranean formation;
flowing an uncombusted portion of the dual-duty agent through the heated zone
to heat the
uncombusted portion of the dual-duty agent and generate a heated dual-duty
agent; and
contacting the viscous hydrocarbons with the heated dual-duty agent to
generate heated and
diluted hydrocarbons which have a lower viscosity than the viscous
hydrocarbons via dilution
with the heated dual-duty agent.
[0009c] Certain exemplary embodiments can provide a method of heating and
diluting
viscous hydrocarbons within a subterranean formation, the method comprising:
continuously
supplying a dual-duty agent comprising a diluent to the subterranean
formation; periodically
supplying an oxidant to the subterranean formation; combusting a combusted
portion of the
dual-duty agent with the oxidant in a heated zone of the subterranean
formation during the
periodically supplying; flowing an uncombusted portion of the dual-duty agent
through the
heated zone to heat the uncombusted portion of the dual-duty agent and
generate a heated
dual-duty agent; and contacting the viscous hydrocarbons with the heated dual-
duty agent to
generate heated and diluted hydrocarbons which have a lower viscosity than the
viscous
hydrocarbons via dilution with the heated dual-duty agent.
[0009d] Certain exemplary embodiments can provide a method of heating and
diluting
viscous hydrocarbons within a subterranean formation, the method comprising:
periodically
supplying a dual-duty agent comprising a diluent to the subterranean
formation; periodically
supplying an oxidant to the subterranean formation; combusting a combusted
portion of the
dual-duty agent with the oxidant in a heated zone of the subterranean
formation during the
periodically supplying; flowing an uncombusted portion of the dual-duty agent
through the
heated zone to heat the uncombusted portion of the dual-duty agent and
generate a heated
dual-duty agent; and contacting the viscous hydrocarbons with the heated dual-
duty agent to
generate heated and diluted hydrocarbons which have a lower viscosity than the
viscous
hydrocarbons via dilution with the heated dual-duty agent.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] Fig. 1 is a schematic cross-sectional view of an illustrative,
non-exclusive
example of a viscous hydrocarbon production assembly that may include and/or
utilize the
systems and methods according to the present disclosure.
[0011] Fig. 2 is a schematic transverse cross-sectional view of an
illustrative, non-
exclusive example of a combined injection and production wellbore that may
form a portion
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of the viscous hydrocarbon production assembly of Fig. I.
[0012] Fig. 3 is a schematic transverse cross-sectional view of an
illustrative, non-
exclusive example of separate injection and production wellbores that may form
a portion of
the viscous hydrocarbon production assembly of Fig. I.
[0013] Fig. 4 is a schematic representation of an illustrative, non-
exclusive example
comparing the hydrocarbon production vs. cycle number for a production-
enhancing method
according to the present disclosure with that of a prior art production-
enhancing method.
[0014] Fig. 5 is a flowchart depicting methods according to the
present disclosure of
heating and diluting viscous hydrocarbons that are present within a
subterranean formation.
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[0015] Fig. 6 is a flowchart depicting methods according to the present
disclosure of
enhancing production of viscous hydrocarbons from a subterranean formation.
DETAILED DESCRIPTION AND BEST MODE OF THE DISCLOSURE
[0016] Fig. 1 is a schematic cross-sectional view of an illustrative, non-
exclusive
example of a viscous hydrocarbon production assembly 10 that may include
and/or utilize the
systems and methods according to the present disclosure. The viscous
hydrocarbon
production assembly of Fig. 1 includes at least one well 12 that includes at
least one wellbore
20 that defines a wellbore conduit 22. The wellbore conduit extends between a
surface
region 30 and a subterranean formation 42 that is present within a subsurface
region 40. Figs.
2-3 provide schematic transverse cross-sectional views of wellbore(s) 20 of
Fig. 1.
[0017] As illustrated in Fig. 1, viscous hydrocarbon production assembly
10 further
includes a dual-duty agent supply system 50 that is configured to selectively
supply a dual-
duty agent 52, which also may be referred to herein as a dual-duty agent
stream 52, through
wellbore conduit 22 and to subterranean formation 42. Viscous hydrocarbon
production
assembly 10 also includes an oxidant supply system 60 that is configured to
selectively
supply an oxidant 62, which also may be referred to herein as an oxidant
stream 62, through
wellbore conduit 22 and to subterranean formation 42.
[0018] The viscous hydrocarbon production assembly further may include a
control
system 90 that is programmed and/or otherwise configured to control the
operation of at least
.. a portion of the viscous hydrocarbon production assembly. In addition,
viscous hydrocarbon
production assembly 10 also may include a hydrocarbon production system 86.
Hydrocarbon
production system 86 additionally or alternatively may be referred to herein
as a viscous
hydrocarbon production system 86 and/or as a heated and diluted hydrocarbon
production
system 86, that is configured to produce heated and diluted hydrocarbons 49
from the
subterranean formation. Heated and diluted hydrocarbons 49 also may be
referred to herein
as a heated and diluted hydrocarbon stream 49.
[0019] Dual-duty agent supply system 50, oxidant supply system 60, heated
and diluted
hydrocarbon production system 86, and control system 90 are illustrated as
being separate
and/or distinct from well 12 in Fig. 1. However, it is within the scope of the
present
disclosure that any suitable component of viscous hydrocarbon production
assembly 10 may
be integrated into and/or form a portion of any other suitable portion of the
viscous
hydrocarbon production assembly. As illustrative, non-exclusive examples, at
least a portion
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of the dual-duty agent supply system, the oxidant supply system, the heated
and diluted
hydrocarbon production system, and/or the control system may be integrated
into and/or
located within one or more well(s) 12 and/or wellbore conduit(s) 22 thereof
[0020] Subterranean formation 42 may be any suitable structure that
includes and/or
contains one or more viscous hydrocarbons 46. As illustrative, non-exclusive
examples,
subterranean formation 42 may include and/or be an oil sands formation, a tar
sands
formation, and/or a bituminous sands formation that may contain viscous
hydrocarbons 46.
Illustrative, non-exclusive examples of viscous hydrocarbons 46 include
bitumen, tar, and/or
other unconventional hydrocarbon reserves. These unconventional hydrocarbon
reserves
may include hydrocarbons with a viscosity that is too high to be produced from
the
subterranean formation using traditional primary and/or secondary hydrocarbon
recovery
operations without first decreasing the viscosity thereof. This may be due to
the fact that
these primary and/or secondary hydrocarbon recovery operations may rely upon a
pressure
head to flow hydrocarbons from the subterranean formation.
[0021] Subterranean formation 42 also may include reservoir solids 44, and
viscous
hydrocarbons 46 may be distributed between, adsorbed on, and/or adhered to the
reservoir
solids. Illustrative, non-exclusive examples of reservoir solids according to
the present
disclosure include sand, rock, a solid structure, and/or a matrix material
that may be present
within and/or define a portion of the subterranean formation.
[0022] Dual-duty agent supply system 50 may include any suitable structure
that is
configured to provide dual-duty agent 52 to subterranean formation 42 via
wellbore conduit
22. As illustrative, non-exclusive examples, the dual-duty agent supply system
may include
one or more valves, pumps, compressors, pipes, and/or storage tanks that may
be configured
to store the dual-duty agent and/or to control a flow of the dual-duty agent
between surface
.. region 30 and subterranean formation 42. The dual-duty agent supply system
also may
include a pre-heater 56 that is configured to heat, or pre-heat, the dual-duty
agent prior to
supply of the dual-duty agent to the subterranean formation.
[0023] Illustrative, non-exclusive examples of dual-duty agents 52
according to the
present disclosure, which additionally or alternatively may be referred to
herein as dual-duty
diluents 52, include any suitable fluid that is both flammable and/or
combustible and that
may function as a diluent for at least a portion of viscous hydrocarbons 46
that are contained
within the subterranean formation. Thus, dual-duty agents 52 additionally or
alternatively
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may be referred to herein as being soluble in viscous hydrocarbons 46,
dissolving in viscous
hydrocarbons 46, and/or decreasing the viscosity of viscous hydrocarbons 46.
More specific
but still illustrative, non-exclusive examples of dual-duty agents 52
according to the present
disclosure include methane, ethane, propane, butane, pentane, hexane, heptane,
octane,
nonane, decane, dimethyl ether, a normal or an isomeric alkane, a normal or an
isomeric
alkene, naphtha, natural gas condensate or condensates, gas plant condensate
or condensates,
and/or mixtures that include one or more of the above materials.
[0024] As discussed, dual-duty agent 52 may include and/or be a diluent,
which also may
be referred to herein as a filler, a dilutent, a thinner, and/or a diluting
agent. Thus, the dual-
duty agent may include and/or be a material that, when added to viscous
hydrocarbons 46,
decreases the viscosity thereof. This decrease in viscosity may provide for,
permit, and/or
enable flow of the viscous hydrocarbons within subterranean formation 42, flow
of the
viscous hydrocarbons within a pore space that may be present between reservoir
solids 44
that form a portion of the subterranean formation, and/or flow of the viscous
hydrocarbons
from subterranean formation 42 to surface region 30 via wellbore conduit 22.
This decrease
in viscosity also may include decreasing the viscosity of the viscous
hydrocarbons such that
the viscous hydrocarbons begin to flow within the subterranean formation
and/or the wellbore
conduit and/or decreasing the viscosity of the viscous hydrocarbons to
decrease a magnitude
of a driving force (such as a pressure differential) that is needed to permit
flow of the viscous
.. hydrocarbons through the subterranean formation and/or the wellbore conduit
at a desired, or
target, flow rate.
[0025] Oxidant supply system 60 may include any suitable structure that
is configured to
selectively supply oxidant 62 to subterranean formation 42 via wellbore
conduit 22. As
illustrative, non-exclusive examples, oxidant supply system 60 may include one
or more
.. pumps, compressors, valves, storage tanks, and/or fluid conduits that may
be configured to
retain and/or control the flow of oxidant 62, such as oxygen, air, oxygen-
enriched air, or a
chemical oxidant, to the subterranean formation.
[0026] Heated and diluted hydrocarbon production system 86 may include
any suitable
structure that is configured to convey heated and diluted hydrocarbons 49 from
subterranean
.. formation 42 via wellbore conduit 22. As illustrative, non-exclusive
examples, heated and
diluted hydrocarbon production system 86 may include and/or utilize any
suitable pressure
head, gravitational force, pump, and/or other structure to provide a motive
force to convey
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heated and diluted hydrocarbons 49 from subterranean formation 42 into
wellbore conduit 22
and/or through wellbore conduit 22, as well as from the subterranean formation
to surface
region 30.
[0027] Control system 90 may include any suitable structure that is
adapted, configured,
designed, selected, and/or programmed to control the operation of at least a
portion of viscous
hydrocarbon production assembly 10. As an illustrative, non-exclusive example,
control
system 90 may include and/or be in communication with one or more detectors 92
that may
be configured to detect one or more properties of viscous hydrocarbon
production assembly
and/or any suitable component thereof and/or material that is contained
therein.
10 Illustrative, non-exclusive examples of properties that may be detected
by detectors 92
include any suitable temperature, pressure, chemical composition, and/or flow
rate of viscous
hydrocarbons 46, subterranean formation 42, heated and diluted hydrocarbons
49, and/or
dual-duty agent 52.
[0028] As another illustrative, non-exclusive example, control system 90
may control the
operation of the viscous hydrocarbon production assembly based, at least in
part, on the
detected properties. As illustrative, non-exclusive examples, this may include
controlling a
flow rate of dual-duty agent 52 and/or oxidant 62. As another illustrative,
non-exclusive
example, this may include initiating and/or increasing a flow of oxidant 62
responsive to
detecting a temperature that is less than a threshold temperature. As yet
another illustrative,
non-exclusive example, this may include ceasing and/or decreasing the flow of
oxidant 62
responsive to detecting a temperature that is greater than a threshold
temperature. Additional
illustrative, non-exclusive examples of control strategies for controller 90
are discussed in
more detail herein with reference to methods 200, 300 of Figs. 5-6.
[0029] As illustrated in Fig. 1, detectors 92 may be associated with any
suitable portion
of the viscous hydrocarbon production assembly. As illustrative, non-exclusive
examples,
one or more detectors 92 may be associated with, located within, and/or form a
portion of
well 12, dual-duty agent supply system 50, oxidant supply system 60, heated
and diluted
hydrocarbon production system 86, wellbore conduit 22, and/or subterranean
formation 42.
Illustrative, non-exclusive examples of detectors 92 include any suitable
temperature
detector, pressure detector, differential pressure detector, chemical
composition detector,
and/or viscometer. Illustrative, non-exclusive examples of properties that may
be detected by
detectors 92 include any suitable temperature, pressure, differential
pressure, chemical
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composition, and/or viscosity.
[0030] It is within the scope of the present disclosure that viscous
hydrocarbon
production assembly 10 may be utilized and/or controlled in any suitable
manner and that this
may include automated and/or manual control. As illustrative, non-exclusive
examples,
control system 90 may control the operation of viscous hydrocarbon production
assembly 10
using methods 200, 300 that are discussed in more detail herein with reference
to Figs. 5-6.
As another illustrative, non-exclusive example, at least a portion of the
operation of the
viscous hydrocarbon production assembly may be controlled manually and/or by
an operator
of the viscous hydrocarbon production assembly. This also may include
performing at least a
.. portion of methods 200, 300 that are discussed in more detail herein.
[0031] With continued reference to Figs. 1-3, viscous hydrocarbon
production assembly
10 may be configured to both heat and dilute viscous hydrocarbons 46 that may
be present
within subterranean formation 42, thereby decreasing the viscosity of the
viscous
hydrocarbons and increasing a flow of the viscous hydrocarbons through
subterranean
formation 42 to wellbore conduit 22 and/or through wellbore conduit 22 to
surface region 30.
Thus, viscous hydrocarbon production assembly 10 may increase recovery and/or
production
of viscous hydrocarbons that might otherwise be difficult and/or costly to
remove (or remove
by pumping) from subterranean 42 due to the high viscosity thereof.
[0032] Viscous hydrocarbon production assembly 10 may include a well 12
that may
function as both an injection well 14 and a production well 16, with the
operation of injection
well 14 and production well 16 being discussed in more detail herein. This is
illustrated in
Fig. 1 by first well 26. Under these conditions, and as illustrated in dashed
lines in Fig. 1, the
viscous hydrocarbon production assembly further may include an auxiliary well
18 that
extends from surface region 30. At least a portion of auxiliary well 18 may
extend adjacent
to first well 26, may be proximal to first well 26, may be in fluid
communication with first
well 26, and/or may intersect first well 26 within subterranean formation 42.
As also
illustrated in Fig. 1, auxiliary well 18 (when present) optionally may convey
dual-duty agent
52 and/or oxidant 62 from surface region 30 to first well 26. Additionally or
alternatively,
auxiliary well 18 may include and/or be a vent well that is configured to
convey a combustion
product stream 76 from first well 26 to surface region 30.
[0033] When auxiliary well 18 conveys at least two of dual-duty agent 52,
oxidant 62,
and combustion product stream 76 between the surface region and the first
well, the auxiliary
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well may include and/or define a plurality of respective wellbore conduits 22,
such as through
inclusions of a plurality of pipes therein. This may permit conveying the
respective materials
without mixing therein and/or may permit mixing of the respective materials
within a desired
portion, or region, of the auxiliary well. Additionally or alternatively, the
respective plurality
of wellbore conduits 22 may be defined within first well 26 and/or a second
well 28, which is
discussed in more detail herein.
[0034] However, the viscous hydrocarbon production assembly also may
include more
than one well 12. This is illustrated in Fig. 1 by first well 26 and optional
second well 28.
When the viscous hydrocarbon production assembly includes both first well 26
and second
well 28, one well (such as first well 26) may be production well 16 and one
well (such as
second well 28) may be injection well 14.
[0035] Regardless of whether the viscous hydrocarbon production assembly
includes one
well, two wells, or more than two wells. production well 16 may be configured
to produce
heated and diluted hydrocarbons 49 from subterranean formation 42 to surface
region 30. In
.. addition, injection well 14 may be configured to provide dual-duty agent 52
and oxidant 62 to
subterranean formation 42, thereby generating heated and diluted hydrocarbons
49, as
discussed in more detail herein.
[0036] It is also within the scope of the present disclosure that viscous
hydrocarbon
production assembly 10 may include more than two wells. As illustrative, non-
exclusive
examples, the viscous hydrocarbon production assembly may include 3 wells, 4
wells, 5
wells, 6 wells, 7 wells, 8 wells, or more than 8 wells. When the viscous
hydrocarbon
production assembly includes a plurality of wells 12, it is within the scope
of the present
disclosure that each well may function as both an injection well 14 and a
production well 16.
However, it is also within the scope of the present disclosure that a first
portion of wells 12
may be injection wells 14, while a second portion of wells 12 may be
production wells 16,
and a number of injection wells 14 may be less than, equal to, or greater than
a number of
production wells 16.
[0037] Well(s) 12 may include any suitable hydrocarbon well and may
include any
suitable orientation within subsurface region 40. As illustrative, non-
exclusive examples,
well(s) 12 may include a vertical portion, a deviated portion, and/or a
horizontal portion.
When well(s) 12 include the horizontal portion, the horizontal portion may
extend within
subterranean formation 42, as illustrated in Fig. 1.
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[0038] Regardless of the particular well configuration and the presence
of one well, two
wells, or more than two wells within viscous hydrocarbon production assembly
10, injection
well 14 may be configured to convey dual-duty agent 52 and oxidant 62 to the
subterranean
formation. As discussed in more detail herein with reference to methods 200
and 300,
.. oxidant 62 may be mixed with a first portion of dual-duty agent 52 within
well 12 to generate
a combustible mixture 74 of the dual-duty agent and the oxidant. Combustible
mixture 74
may be combusted within a heated zone 70 that is present within subterranean
formation 42,
thereby heating heated zone 70, and an ignition source 72 may initiate
combustion of
combustible mixture 74 within the heated zone.
[0039] The first portion of dual-duty agent 52 also may be referred to
herein as the
combusted portion of dual-duty agent 52, the portion of dual-duty agent 52
that is combusted
within heated zone 70, and/or the portion of dual-duty agent 52 that is to be
combusted. The
first portion of the dual-duty agent includes a portion, fraction, or
percentage of dual-duty
agent 52 (and/or a flow or stream thereof) that is supplied to heated zone 70
with,
concurrently with, and/or in parallel to supply of oxidant 62 to the heated
zone. Thus, the
combusted portion of dual-duty agent 52 combines with oxidant 62 to form
combustible
mixture 74, which is subsequently combusted within the heated zone. The
combusted portion
of dual-duty agent 52 may not be premixed with oxidant 62 within wellbore 20
of well 12
and/or may not be mixed with oxidant 62 prior to being received within heated
zone 70.
[0040] Subsequent to combustion of combustible mixture 74, flow of oxidant
62 to
subterranean formation 42 may be stopped, which may stop and/or cease
combustion of dual-
duty agent 52 therein (such as due to the lack of oxidant within the
subterranean formation).
This is discussed in more detail herein with reference to methods 200 and 300.
However,
flow of a second portion of dual-duty agent 52 through injection well 14 may
continue. The
second portion of dual-duty agent 52 also may be referred to herein as an
uncombusted
portion of dual-duty agent 52 and/or as a portion of dual-duty agent 52 that
is not combusted
within heated zone 70.
[0041] The second portion of the dual-duty agent includes a portion,
fraction, and/or
percentage of the dual-duty agent (and/or a flow and/or stream thereof) that
is supplied to
injection well 14, subterranean formation 42, and/or heated zone 70 prior to
supply of oxidant
62 to the heated zone, after supply of oxidant 62 to the heated zone, and/or
when oxidant 62
is not being supplied to the heated zone. Additionally or alternatively, the
second portion of
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dual-duty agent 52 also may include a fraction of the dual-duty agent that is
present within
combustible mixture 74 but that does not combust within heated zone 70, such
as due to
incomplete combustion of the dual-duty agent that is present within
combustible mixture 74.
[0042] The second portion of the dual-duty agent may flow through heated
zone 70 and
be heated therein before flowing out of the heated zone as a heated dual-duty
agent 54, which
also may be referred to herein as a heated dual-duty agent stream 54. Heated
dual-duty agent
54 may contact viscous hydrocarbons 46 within subterranean formation 42,
thereby
producing heated and diluted hydrocarbons 49.
[0043] Heated zone 70 may include and/or be any suitable portion of
and/or location
within subsurface region 40 and/or subterranean formation 42. As an
illustrative, non-
exclusive example, heated zone 70 may include a portion of well 12, a portion
of wellbore
20, and/or wellbore conduit 22 thereof that extends within subterranean
formation 42.
Additionally or alternatively, heated zone 70 may include a portion of
subterranean formation
42 that is away from, adjacent, and/or in close proximity to, well 12. Heated
zone 70 may
include reservoir solids 44 with void or pore space therein that may be heated
by combustion
therein. In addition, reservoir solids 44 that are adjacent to, are proximal
to, and/or are in
thermal contact with heated zone 70 also may be heated by this combustion.
[0044] Heated zone 70 may be placed away from the well 14 and/or well 16
so as not to
expose the well to excessive heat emanating from the heated zone 70. To carry
the heat from
.. heated zone 70 to the parts of subterranean formation 42 where heat is
needed, a heat pipe 78
may be installed in and/or around heated zone 70. Although not required to all
embodiments,
the heat pipe, when present, may include and/or be a latent heat transferring
device that does
not include any moving parts, such as a sealed heat transfer device that
contains a heat
transfer fluid that boils at a lower temperature than that of formation 42
and/or heated zone
70. The heat transfer fluid at an end of the tube that is closer to heated
zone 70 may vaporize
and extract its latent heat of vaporization from heated zone 70. When this
vapour reaches a
cooler end of the heat pipe, it may condense and transfer the latent heat to
the zone away
from zone 70.
[0045] The heat pipe may be vertical and/or horizontal. A horizontal
metal wick (wire
mesh) may be placed inside the pipe to transfer the condensed transfer fluid
to the hotter end
by capillary action. Auxiliary well 18 in Fig. 1 and/or another auxiliary well
may act as
and/or include the heat pipe. Additionally or alternatively, a lateral heat
pipe may be drilled
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from auxiliary well 18, injection well 14 and/or production well 16. The
uncombusted
portion of the dual-duty agent may be heated by the heat transferred from
heated zone 70 by
the heat pipe, with or without traversing through the heated zone.
[0046] Heated dual-duty agent 54 may flow through subterranean formation
42 and
contact viscous hydrocarbons 46 that are present therein, such as in a heat
transfer zone 80
thereof. Upon contacting the viscous hydrocarbons, the dual duty agent may
both dilute the
viscous hydrocarbons and transfer thermal energy to the viscous hydrocarbons
(i.e., heat the
viscous hydrocarbons) to generate heated and diluted hydrocarbons 49. As
discussed herein,
heated and diluted hydrocarbons 49 may have a viscosity that is significantly
less than a
viscosity of viscous hydrocarbons 46, thereby permitting the heated and
diluted hydrocarbons
to flow within subterranean formation 42 to wellbore conduit 22 of production
well 16 and/or
through wellbore conduit 22 of production well 16 to surface region 30.
[0047] As discussed, heated and diluted hydrocarbons 49 may include
viscous
hydrocarbons 46 that have been heated by, and diluted with, heated dual-duty
agent 54 to
decrease the viscosity thereof. Thus, heated and diluted hydrocarbons 49 may
have a
temperature, or average temperature, that is greater than an ambient
temperature within the
subterranean formation prior to combustion of dual-duty agent 52 and oxidant
62 therein
and/or greater than a temperature of the viscous hydrocarbons prior to contact
with heated
dual-duty agent 54. Additionally or alternatively, heated and diluted
hydrocarbons 49 may
have a temperature of at least 15 C, at least 20 C, at least 25 C, at least
30 C, at least 35
C, at least 40 C, at least 45 C, at least 50 C, at least 55 C, at least 60
C, at least 65 C, at
least 70 C, at least 75 C, at least 80 C, at least 85 C, at least 90 C,
at least 95 C, or at
least 100 C.
[0048] Additionally or alternatively, heated and diluted hydrocarbons 49
may have a
viscosity, or average viscosity, that is less than an average viscosity of the
viscous
hydrocarbons prior to combustion of dual-duty agent 52 and oxidant 62 within
the
subterranean formation and/or less than a viscosity of the viscous
hydrocarbons prior to
contact with heated dual-duty agent 54. As illustrative, non-exclusive
examples, the viscosity
of heated and diluted hydrocarbons 49 may be at least 2, at least 3, at least
4, at least 5, at
least 10, at least 25, at least 50, at least 100, at least 250, at least 500,
at least 750, or at least
1000 times lower than the average viscosity of the viscous hydrocarbons prior
to combustion
of dual-duty agent 52 and oxidant 62 within the subterranean formation and/or
prior to
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contact with heated dual-duty agent 54.
[0049] As discussed, heated and diluted hydrocarbons 49 include viscous
hydrocarbons
46 and heated dual-duty agent 54. It is within the scope of the present
disclosure that the
heated and diluted hydrocarbons also may include one or more additional
materials. As an
illustrative, non-exclusive example, combustion of dual-duty agent 52 and
oxidant 62 may
generate one or more combustion products, such as water and/or carbon dioxide.
These
combustion products may diffuse and/or flow within subterranean formation 42
and may
absorb within, may dissolve within, and/or may dilute viscous hydrocarbons 46
and/or heated
and diluted hydrocarbons 49.
[0050] Thus, the heated and diluted hydrocarbons further may include the
combustion
products. Mixing of the combustion products into and/or dissolution of the
combustion
products within viscous hydrocarbons 46 and/or heated and diluted hydrocarbons
49 further
may decrease the viscosity of the generated heated and diluted hydrocarbons.
As an
illustrative, non-exclusive example, the water may transfer a significant
amount of thermal
energy to the heated and diluted hydrocarbons (through condensation from steam
that is
generated during the combustion). As another illustrative, non-exclusive
example, the carbon
dioxide may act as a further diluent for the viscous hydrocarbons.
[0051] As discussed, and illustrated in Figs. 1 and 2, first well 26 may
be both injection
well 14 and production well 16. Under these conditions, viscous hydrocarbon
production
assembly 10 may be configured to provide both dual-duty agent 52 and oxidant
62 to
subterranean formation 42, producing combustible mixture 74 therein, for a
first supply time.
During the first supply time, combustible mixture 74 may be combusted within
heated zone
70, thereby heating the heated zone.
[0052] Subsequently, the viscous hydrocarbon production assembly may
cease supplying
the oxidant but continue supplying the dual-duty agent to the subterranean
formation, thereby
ceasing the combustion within heated zone 70, for a second supply time. During
the second
supply time, the dual-duty agent may flow through the heated zone and be
heated therein to
generate heated dual-duty agent 54. The heated dual-duty agent may contact
viscous
hydrocarbons 46, thereby producing heated and diluted hydrocarbons 49. The
second supply
time may be greater than the first supply time. Additionally or alternatively,
the viscous
hydrocarbon production assembly may convey a greater volume of the dual-duty
agent to the
subterranean formation during the second supply time than was conveyed to the
subterranean
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formation during the first supply time.
[0053] Subsequent to the second supply time, the viscous hydrocarbon
production
assembly may cease supplying the dual-duty agent to the subterranean
formation. Upon
ceasing the supply of the dual-duty agent to the subterranean formation,
pressure within
subterranean formation 42 that may be generated during the first supply time
and/or the
second supply time may provide a motive force for flow of heated and diluted
hydrocarbons
49 from the subterranean formation into wellbore conduit 22 and/or through the
wellbore
conduit to surface region 30 as a produced heated and diluted hydrocarbon
stream 88.
Heated and diluted hydrocarbon production system 86 may control the production
of
produced heated and diluted hydrocarbon stream 88 from the production well.
[0054] Alternatively, and as also discussed, and illustrated in Figs. 1
and 3, viscous
hydrocarbon production assembly 10 may include more than one well 12, such as
separate
production 16 and injection 14 wells, with first well 26 and second well 28
respectively
providing a more specific illustrative, non-exclusive example of such a
configuration. Under
these conditions, viscous hydrocarbon production assembly 10 may be configured
to
continuously, or at least substantially continuously, supply dual-duty agent
52 to the
subterranean formation via injection well 14 and to selectively,
intermittently, and/or
periodically supply oxidant 62 to injection well 14.
[0055] When oxidant 62 is supplied to the injection well, the oxidant may
mix with the
combusted portion of the dual-duty agent therein, thereby producing
combustible mixture 74,
and the combustible mixture may be ignited within heated zone 70. When oxidant
62 is not
supplied to the injection well, the uncombusted portion of the dual-duty agent
may flow
through the heated zone and be heated before contacting viscous hydrocarbons
46 to generate
heated and diluted hydrocarbons 49.
[0056] Concurrently, heated and diluted hydrocarbons 49 may flow through
subterranean
formation 42 to wellbore conduit 22 of production well 16. The heated and
diluted
hydrocarbons may then flow through production well 16 to surface region 30,
and flow
thereof may be controlled by heated and diluted hydrocarbon production system
86.
[0057] When viscous hydrocarbon production assembly 10 includes separate
injection
wells 14 and production wells 16, such as second well 28 and first well 26,
respectively, at
least a parallel portion of injection well 14 may be parallel to, or at least
substantially parallel
to, a parallel portion of production well 16, as illustrated in Figs. 1 and 3.
In addition, and
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also as illustrated in Figs. 1 and 3, the parallel portion of injection well
14 may be at least
substantially horizontal and may be located vertically, or at least
substantially vertically,
above the parallel portion of production well 16, which also may be at least
substantially
horizontal. This may permit heated and diluted hydrocarbons 49 that are
generated by
introduction of heated dual-duty agent 54 into injection well 14 to flow under
the influence of
gravity within subterranean formation 42 to wellbore conduit 22 of production
well 16.
[0058] It is within the scope of the present disclosure that, as
discussed in more detail
herein with reference to methods 200, 300, viscous hydrocarbon production
assembly 10
further may include and/or utilize additional production-enhancing processes
in combination
with the production-enhancing processes that are disclosed herein. As
illustrative, non-
exclusive examples, and when the viscous hydrocarbon production assembly
includes a
single well 12 that functions as both injection well 14 and production well 16
(such as first
well 26 of Figs. 1 and 2), the systems and methods disclosed herein further
may include
and/or be utilized with any suitable traditional cyclic production-enhancing
process, such as a
cyclic solvent process (CSP) and/or cyclic steam injection (CSS). As
additional illustrative,
non-exclusive examples, and when the viscous hydrocarbon production assembly
includes
separate injection 14 and production 16 wells (such as second well 28 and
first well 26,
respectively, of Has. 1 and 3), the systems and methods disclosed herein
further may include
and/or be utilized with any suitable traditional continuous, or quasi-
continuous, production-
.. enhancing process, such as steam-assisted gravity drainage (SAGD), solvent-
assisted steam-
assisted gravity drainage (SA-SAGD), steamflooding, heated solvent, heated
vapor extraction
(VAPEX), and/or non-heated vapor extraction (VAPEX).
[0059] In addition, and as discussed in more detail herein with reference
to methods 200,
300, it is also within the scope of the present disclosure that the systems
and methods
disclosed herein may be combined with the cyclic and/or continuous production-
enhancing
processes in any suitable manner. As an illustrative, non-exclusive example,
one or more of
the traditional production-enhancing processes may be an initial, first, or
primary production-
enhancing process that is performed within subterranean formation 42 prior to
performing
methods 200, 300. Under these conditions, methods 200, 300 may be referred to
herein as
subsequent, second, and/or secondary production-enhancing processes.
[0060] Additionally or alternatively, one or more of the traditional
production-enhancing
processes may be a subsequent, second, and/or secondary production-enhancing
process that
CA 02804521 2013-01-31
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is performed within subterranean formation 42 after performing methods 200,
300. Under
these conditions, methods 200, 300 may be referred to herein as primary,
first, and/or initial
production-enhancing processes.
[0061] Performing methods 200, 300 in addition to and/or in place of the
traditional
cyclic and/or continuous production-enhancing processes that are discussed
above may
provide significant benefits over performing only the traditional production-
enhancing
processes. As an illustrative, non-exclusive example, the traditional
production-enhancing
processes often may generate two liquid hydrocarbon phases that include
viscous
hydrocarbons 46, such as a light, or upper, phase and a heavy, or lower,
phase.
[0062] The light phase that is produced by a traditional production-
enhancing process
may be readily produced from the subterranean formation without further
processing.
However, the heavy phase produced by such a process may be difficult to remove
from the
subterranean formation due to a high viscosity of the heavy phase. Thus, it
may be necessary
to either leave the heavy phase within the subterranean formation or perform
additional
production-enhancing processes, such as injection of a supplemental, or heavy,
diluent
(and/or dual duty agent) into the subterranean formation, to further decrease
the viscosity of
the heavy phase. Leaving the heavy phase in the formation may decrease the
overall viscous
hydrocarbons production from the subterranean formation and/or decrease a
proportion of the
viscous hydrocarbon in place that may be produced from the subterranean
formation.
Likewise, performing additional production-enhancing processes may increase a
cost
associated with producing the viscous hydrocarbons from the subterranean
formation.
[0063] In contrast, the systems and methods disclosed herein, when
performed alone
and/or in conjunction with the traditional production-enhancing process, may
decrease,
suppress, and/or eliminate formation of the heavy phase. This suppression of
formation of
the heavy phase may be due to the concurrent heating and diluting of viscous
hydrocarbons
46 to produce heated and diluted hydrocarbons 49 that may be accomplished with
the systems
and methods that are disclosed herein.
[0064] As another illustrative, non-exclusive example, it may be
difficult and/or
impossible to control the temperature of the subterranean formation using the
traditional
production-enhancing processes due to a lack of heat generation and/or an
inconsistent/unpredictable heat generation thereby. In contrast, the systems
and methods
disclosed herein provide for selective supply of oxidant 62 to the
subterranean formation to
16
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control the temperature thereof. This may decrease a potential for damage to
the
subterranean formation, damage to the viscous hydrocarbon production assembly
by
maintaining the temperature of the subterranean formation below an upper
threshold
temperature, and/or formation of undesired combustion products within the
subterranean
formation. As an illustrative, non-exclusive example, a flow rate of oxidant
62 may be
decreased and/or stopped to decrease the temperature of the subterranean
formation. As
another illustrative, non-exclusive example, the flow rate of oxidant 62 may
be initiated
and/or increased to increase the temperature of the subterranean formation.
[0065] As another illustrative, non-exclusive example, it may be
difficult to control the
combustion products that may be produced during a traditional in situ
combustion process.
In contrast, the dual-duty agent according to the present disclosure may be
selected such that
the combustion products thereof are primarily water/steam and carbon dioxide.
[0066] As discussed, the systems and methods disclosed herein may be used
in
combination with more traditional production-enhancing processes to improve
the overall
production of viscous hydrocarbons from the subterranean formation. Fig. 4 is
a schematic
representation of an illustrative, non-exclusive example comparing the
hydrocarbon
production vs. time (or cycle number) for a production-enhancing process 98
according to the
present disclosure with that of a prior art production-enhancing process 96.
Both process 96
and process 98 utilize a single well for both injection of and production from
the subterranean
formation (such as first well 26 of Figs. 1 and 2).
[0067] Process 96 is a traditional cyclic solvent process, in which a
diluent is injected
into a wellbore that extends within the subterranean formation for an
injection time. The
diluent contacts and dilutes viscous hydrocarbons that are present within the
subterranean
formation. Subsequently, supply of the diluent to the subterranean formation
is stopped, and
the viscous hydrocarbons are produced from the subterranean formation for a
production
time. In Fig. 4, the process has been repeated a total of seven cycles, and
the cumulative
hydrocarbon production from the subterranean formation is shown to increase as
a result of
each cycle.
[0068] Process 98 is substantially similar to process 96 for cycles 1-4
and 6-7. However,
at the beginning of cycle 5, the diluent is utilized as a dual-duty agent.
Thus, a combusted
portion of the diluent is combusted within a heated zone of the subterranean
formation using
the systems and methods that are disclosed herein. Subsequently, an
uncombusted portion of
17
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the diluent is flowed through the heated zone and into the subterranean
formation. As
discussed, this uncombusted portion of the diluent is heated by flow through
the heated zone
and subsequently heats and dilutes the viscous hydrocarbons that are present
within the
subterranean formation, thereby increasing an overall efficiency of the
production-enhancing
process.
[0069] This is illustrated by the increased cumulative hydrocarbon
production that is
shown in Fig. 4 for process 98 when compared to process 96. It is noteworthy
that increased
cumulative hydrocarbon production is observed during cycles 5, 6, and 7
despite the fact that
the diluent is only combusted at the beginning of cycle 5, with cycles 6 and 7
being cycles of
the traditional cyclic solvent process.
[0070] Fig. 5 is a flowchart depicting methods 200 according to the
present disclosure of
heating and diluting viscous hydrocarbons that are present within a
subterranean formation.
Methods 200 may include removing viscous hydrocarbons from a heated zone at
205 and/or
pre-heating a dual-duty agent at 210. Methods 200 include supplying the dual-
duty agent to
the subterranean formation at 215, supplying an oxidant to the subterranean
formation at 220,
and combusting a combusted portion of the dual-duty agent and the oxidant in a
heated zone
at 225. Methods 200 further may include ceasing the supplying of the oxidant
while
continuing the supplying of the dual-duty agent at 230. In addition, methods
200 include
flowing an uncombusted portion of the dual-duty agent through the heated zone
to generate a
heated dual-duty agent at 235 and thermally and/or physically contacting the
heated dual-duty
agent with the viscous hydrocarbons to generate heated and diluted
hydrocarbons at 240.
Methods 200 further may include producing the heated and diluted hydrocarbons
from the
subterranean formation at 245 and/or repeating the method at 250.
[0071] Removing the viscous hydrocarbons from the heated zone at 205 may
include
removing a portion, a substantial portion, a majority, or substantially all of
the viscous
hydrocarbons from a portion of the subterranean formation that will include
the heated zone.
It is within the scope of the present disclosure that the removing may be
accomplished in any
suitable manner. As an illustrative, non-exclusive example, the removing may
include
producing the viscous hydrocarbons from the heated zone using any of the
systems and
methods that are disclosed herein.
[0072] Pre-heating the dual-duty agent at 210 may include pre-heating the
dual-duty
agent prior to the supplying at 215. It is within the scope of the present
disclosure that the
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pre-heating may be accomplished in any suitable manner. As an illustrative,
non-exclusive
example, a pre-heater may be utilized to pre-heat the dual-duty agent. As
another illustrative,
non-exclusive example, the pre-heating may include pre-heating the dual-duty
agent in a
surface region that is proximate to a wellbore that extends between the
surface region and the
subterranean formation. As yet another illustrative, non-exclusive example,
the pre-heating
may include solar pre-heating. Still further illustrative, non-exclusive
examples include pre-
heating the dual-duty agent with hot fluid recovered from the subterranean
formation, with
electrical heating, with microwave heating, with infrared heating, with heat
derived (and/or
otherwise generated) by burning a portion of the dual-duty agent, and/or with
heat derived
(and/or otherwise generated) by burning a fossil fuel. When a portion of the
dual-duty agent
is burned (or otherwise combusted) to generate heat for pre-heating additional
portions of the
dual-duty agent, this portion may be referred to as a pre-heating portion
and/or a pre-
combusted portion of the dual-duty agent.
[0073] Supplying the dual-duty agent to the subterranean formation at 215
may include
.. flowing and/or conveying the dual-duty agent through the wellbore and from
the surface
region to the subterranean formation. It is within the scope of the present
disclosure that the
dual-duty agent may be supplied continuously, or at least substantially
continuously, to the
subterranean formation. Alternatively, it is also within the scope of the
present disclosure
that the dual-duty agent may be supplied intermittently, periodically, and/or
cyclically to the
subterranean formation. As an illustrative, non-exclusive example, and as
discussed in more
detail herein, the supplying the dual-duty agent may be stopped and/or ceased
responsive to,
prior to, and/or during the producing at 245. However, and as also discussed
herein, at least a
portion of the dual-duty agent is supplied to the subterranean formation
subsequent to the
supplying the oxidant at 220 and the combusting at 225.
[0074] It is within the scope of the present disclosure that supplying the
dual-duty agent
may include supplying any suitable dual-duty agent, illustrative, non-
exclusive examples of
which are discussed in more detail herein, in any suitable form. As an
illustrative, non-
exclusive example, supplying the dual-duty agent may include supplying a
gaseous,
vaporous, and/or liquid dual-duty agent to the subterranean formation. As
another
illustrative, non-exclusive example, and when the dual-duty agent is supplied
to the
subterranean formation as a liquid, methods 200 further may include vaporizing
the dual-duty
agent within the subterranean formation to generate a vaporous dual-duty
agent.
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[0075]
Supplying the oxidant to the subterranean formation at 220 may include
selectively, periodically, and/or intermittently supplying the oxidant to the
subterranean
formation. As an
illustrative, non-exclusive example, supplying the oxidant to the
subterranean formation at 220 may be performed concurrently with and/or
responsive to a
demand and/or desire for the combusting at 225. It is within the scope of the
present
disclosure that supplying the oxidant to the subterranean formation further
may include
mixing the oxidant with the combusted portion of the dual-duty agent to
generate a
combustible mixture of the dual-duty agent and the oxidant. The mixing may be
performed
in any suitable location, such as in the wellbore, in the subterranean
formation, and/or in the
heated zone. In this regard, it also is within the scope of the disclosure
that the dual-duty
agent and the oxidant may not be mixed in the wellbore, but that they may be
mixed after
being supplied to the subterranean formation and/or to the heated zone
thereof.
[0076]
Combusting the combusted portion of the dual-duty agent and the oxidant at 225
may include combusting to heat the heated zone of the subterranean formation.
As discussed,
the combusted portion of the dual-duty agent also may be referred to herein as
a first portion
of the dual-duty agent, a portion of the dual-duty agent that is combusted
within the heated
zone, and/or a portion of the dual-duty agent that is to be combusted. It is
within the scope of
the present disclosure that the combusting further may include igniting the
combustible
mixture of the dual-duty agent and the oxidant within the heated zone, such as
by actuating
an ignition source that is present within the heated zone.
[0077] As
discussed, the combusting at 225 may generate a gaseous combustion product,
which may include steam, water, and/or carbon dioxide, and methods 200 further
may
include retaining the gaseous combustion product within the subterranean
formation. This
may increase a pressure within the subterranean formation, thereby providing a
driving force
for production of the heated and diluted hydrocarbons from the subterranean
formation at 245
and/or may further heat and/or dilute the viscous hydrocarbons.
[0078] It is
within the scope of the present disclosure that the combusting at 225 may
include combusting a fuel stream that includes the combusted portion of the
dual-duty agent,
as well as one or more additional materials that may be present within the
heated zone, such
as viscous hydrocarbons. As an illustrative, non-exclusive example, the dual-
duty agent may
comprise a majority, at least 60 wt%, at least 65 wt%, at least 70 wt%, at
least 75 wt%, at
least 80 wt%, at least 85 wt%, at least 90 wt%, at least 95 wt%, at least 96
wt%, at least 97
CA 02804521 2013-01-31
2012EM246-CA
wt%, at least 98 wt%, or at least 99 wt% of the fuel stream. As another
illustrative, non-
exclusive example, the additional materials may comprise less than 40 wt%,
less than 35
wt%, less than 30 wt%, less than 25 wt%, less than 20 wt%, less than 15 wt%,
less than 10
wt%, less than 5 wt%, less than 4 wt%, less than 3 wt%, less than 2 wt%, or
less than 1 wt%
of the fuel stream.
[0079] As discussed, the supplying the dual-duty agent at 215 may include
supplying the
dual-duty agent to the subterranean formation independently from the supplying
the oxidant
to the subterranean formation at 220 and/or the combusting at 225.
Additionally or
alternatively, the supplying the dual-duty agent at 215 may be performed prior
to, during,
and/or subsequent to the supplying the oxidant at 220 and/or the combusting at
225, and the
supplying the oxidant at 220 and/or the combusting at 225 may be initiated
based upon any
suitable criteria and/or combination of criteria.
[0080] As illustrative, non-exclusive examples, the supplying at 220
and/or the
combusting at 225 may be initiated based, at least in part, on a selected
and/or predetermined
oxidant supply time and/or period. As another illustrative, non-exclusive
example, and when
the oxidant is supplied to the subterranean formation periodically, the
supplying at 220 and/or
the combusting at 225 may be initiated based, at least in part, on passage of
a threshold
elapsed time since a last and/or prior time that the oxidant was supplied to
the subterranean
formation.
[0081] As yet another illustrative, non-exclusive example, the supplying at
220 and/or the
combusting at 225 may be initiated based, at least in part, on a temperature
of the heated
zone. This may include initiating the supplying at 220 and/or the combusting
at 225 to
maintain the temperature of the heated zone above a threshold lower heated
zone
temperature, illustrative, non-exclusive examples of which include
temperatures of greater
than 15 C, greater than 20 C, greater than 25 C, greater than 30 C,
greater than 35 C,
greater than 40 C, greater than 50 C, greater than 60 C, greater than 70
C, greater than 80
C, or greater than 90 C.
[0082] As another illustrative, non-exclusive example, the supplying at
220 and/or the
combusting at 225 may be initiated based, at least in part, on a property of
the heated and
diluted hydrocarbons, illustrative, non-exclusive examples of which include a
temperature of
the heated and diluted hydrocarbons and/or a viscosity of the heated and
diluted
hydrocarbons. It is within the scope of the present disclosure that the
property of the heated
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and diluted hydrocarbons may be measured at any suitable location,
illustrative, non-
exclusive examples of which include within the subterranean formation, within
the wellbore,
and/or within the surface region.
[0083] As an illustrative, non-exclusive example, the supplying at 220
and/or the
combusting at 225 may be initiated to maintain the temperature of the heated
and diluted
hydrocarbons above a threshold lower hydrocarbon temperature, illustrative,
non-exclusive
examples of which include temperatures of greater than 15 C, greater than 20
C, greater
than 25 C, greater than 30 C, greater than 35 C, greater than 40 C,
greater than 50 C,
greater than 60 C, greater than 70 C, greater than 80 C, or greater than 90
C. As another
illustrative, non-exclusive example, the supplying at 220 and/or the
combusting at 225 may
be initiated to maintain the viscosity of the heated and diluted hydrocarbons
below a
threshold viscosity, illustrative, non-exclusive examples of which include
viscosities of less
than 5000 cP, less than 4500 cP, less than 4000 cP, less than 3500 cP, less
than 3000 cP, less
than 2500 cP, less than 2000 cP, less than 1500 cP, or less than 1000 cP.
[0084] Ceasing the supplying of the oxidant while continuing the supplying
of the dual-
duty agent at 230 may include selectively blocking, stopping, and/or occluding
the supplying
at 220 while permitting and/or continuing the supplying at 215. It is within
the scope of the
present disclosure that the ceasing at 230 also may include and/or be referred
to as ceasing
the combusting, since ceasing the supply of oxidant to the subterranean
formation will starve
the combustion reaction for oxidant, thereby ceasing, or initiating a cease
in, the combustion
reaction that is occurring therein.
[0085] It is within the scope of the present disclosure that the ceasing
may include
ceasing based upon any suitable criteria and/or combination of criteria. As an
illustrative,
non-exclusive example, the ceasing at 230 may be based, at least in part, on
an elapsed time
since the start of the supplying at 220.
[0086] As another illustrative, non-exclusive example, the ceasing at 230
may be based,
at least in part, on the temperature of the heated zone. Thus, the ceasing at
230 may include
ceasing the supplying of oxidant to the subterranean formation to maintain the
temperature of
the heated zone below a threshold upper heated zone temperature, illustrative,
non-exclusive
examples of which include temperatures of less than 900 C, less than 850 C,
less than 825
C, less than 800 C, less than 775 C, less than 750 C, less than 725 C,
less than 700 C,
less than 675 C, less than 650 C, less than 600 C, less than 550 C, or
less than 500 C.
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[0087] As yet another illustrative, non-exclusive example, the ceasing at
230 may be
based, at least in part, on a property of the heated and diluted hydrocarbons,
illustrative, non-
exclusive examples of which are discussed in more detail herein with reference
to the
supplying at 220. As an illustrative, non-exclusive example, the ceasing at
230 may include
.. ceasing the supply of oxidant to the subterranean formation to maintain the
temperature of the
heated and diluted hydrocarbons below a threshold upper hydrocarbon
temperature,
illustrative, non-exclusive examples of which include temperatures of less
than 500 C, less
than 450 C, less than 400 C, less than 375 C, less than 350 C, less than
325 C, less than
300 C, less than 250 C, or less than 200 C. As another illustrative, non-
exclusive example,
the supplying the dual-duty agent to the subterranean formation at 215 may
include supplying
a predetermined volume of the dual-duty agent to the subterranean formation,
and the ceasing
at 230 may be based, at least in part, on combustion of a fraction of the
predetermined
volume of the dual-duty agent. As illustrative, non-exclusive examples, the
ceasing at 230
may be responsive to combustion of at least 0.5 volume %, at least 1 volume %,
at least 2
volume %, at least 3 volume (Vo, at least 4 volume %, at least 5 volume %, at
least 6 volume
%, at least 7 volume %, at least 8 volume %, at least 9 volume %, at least 10
volume %, or at
least 15 volume %, of the predetermined volume of the dual-duty agent.
Additionally or
alternatively, the ceasing at 230 may include ceasing such that less than 30
volume %, less
than 25 volume %, less than 22.5 volume %, less than 20 volume %, less than
17.5 volume
A, less than 15 volume %. less than 12.5 volume %, less than 10 volume %, less
than 7.5
volume %, or less than 5 volume % of the predetermined volume of the dual-duty
agent is
combusted in the subterranean formation.
[0088] Flowing the uncombusted portion of the dual-duty agent through the
heated zone
to generate the heated dual-duty agent at 235 may include heating the
uncombusted portion of
the dual-duty agent within the heated zone. As an illustrative, non-exclusive
example, the
flowing may include thermally contacting the uncombusted portion of the dual-
duty agent
with the heated zone and/or with reservoir solids, such as sand and/or rock,
that may be
present within the heated zone. As another illustrative, non-exclusive
example, the flowing
may include transferring thermal energy from the heated zone to the dual-duty
agent to
generate the heated dual-duty agent. As discussed, the uncombusted portion of
the dual-duty
agent also may be referred to herein as a second portion of the dual-duty
agent and/or a
portion of the dual-duty agent that is not combusted within the heated zone.
[0089] Contacting the viscous hydrocarbons with the heated dual-duty
agent to generate
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the heated and diluted hydrocarbons at 240 may include thermally and/or
physically
contacting the heated dual-duty agent with the viscous hydrocarbons.
Additionally or
alternatively, the contacting at 240 also may include absorbing the heated
dual-duty agent
within the viscous hydrocarbons, mixing the heated dual-duty agent with the
viscous
hydrocarbons, and/or diluting the viscous hydrocarbons with the heated dual-
duty agent. As
discussed, the concurrent heating and diluting of the viscous hydrocarbons
through
combination with the heated and diluted dual-duty agent may significantly
decrease a
viscosity thereof and/or generate heated and diluted hydrocarbons with a
viscosity that is
significantly lower than that of the viscous hydrocarbons.
[0090] As discussed, generating the heated and diluted hydrocarbons through
the
contacting at 240 using the systems and methods that are disclosed herein may
include
generating the heated and diluted hydrocarbons without generating two separate
liquid
hydrocarbon phases that include the viscous hydrocarbon within the
subterranean formation.
Additionally or alternatively, generating the heated and diluted hydrocarbons
through the
contacting at 240 may significantly decrease a volume of the heavy liquid
hydrocarbon phase
when compared to methods that include contacting the viscous hydrocarbons with
an
unheated diluent.
[0091] As illustrative, non-exclusive examples, the contacting at 240 may
include
generating both the heavy liquid hydrocarbon phase and the light liquid
hydrocarbon phase;
however, when both phases are generated, the volume of the heavy liquid
hydrocarbon phase
may comprise less than 25%, less than 20%, less than 15%, less than 10%, less
than 5%, less
than 2.5%, or less than 1% of the volume of the light liquid hydrocarbon
phase. Thus, the
producing at 245 may include producing the heated and diluted hydrocarbons
from the
subterranean formation without supplying a supplemental diluent to the
subterranean
formation to decrease the viscosity of the heavy liquid hydrocarbon phase.
[0092] Producing the heated and diluted hydrocarbons from the
subterranean formation at
245 may include producing the heated and diluted hydrocarbons from a
production well that
extends within the subterranean formation. The producing at 245 may include
producing the
heated and diluted hydrocarbons from the subterranean formation without
supplying steam to
the subterranean formation (other than as a product of the combusting at 225)
and/or without
utilizing the viscous hydrocarbons that are present within the subterranean
formation as a
primary fuel for the combusting at 225.
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[0093] As discussed in more detail herein, the production well may be
separate and/or
distinct from an injection well that receives the dual-duty agent and the
oxidant during the
supplying at 215 and 220 and that defines the heated zone. However, and as
also discussed in
more detail herein, it is also within the scope of the present disclosure that
a single well may
function as both the production well and the injection well.
[0094] When the single well functions as both the production well and the
injection well,
it is within the scope of the present disclosure that an auxiliary well may
intersect the single
well, and at least one of the dual-duty agent and the oxidant may be supplied
to the
production well via the auxiliary well. Additionally or alternatively, methods
200 further
may include venting a combustion product stream from the production well via
the auxiliary
well.
[0095] Repeating the method at 250 may include repeating any suitable
portion of the
method. As an illustrative, non-exclusive example, the repeating at 250 may
include
repeating at least the supplying at 215, the supplying at 220, and the
combusting at 225
subsequent to the ceasing at 230, the flowing at 235, and the contacting at
240 to further heat
and dilute the viscous hydrocarbons that may be present within the
subterranean formation.
[0096] Fig. 6 is a flowchart depicting methods 300 according to the
present disclosure of
enhancing production of viscous hydrocarbons from a subterranean formation.
Methods 300
may include performing an initial production-enhancing process at 305 and
include
converting the viscous hydrocarbons to heated and diluted hydrocarbons at 310.
Methods
300 further may include performing a subsequent production-enhancing process
at 315 and
include producing the heated and diluted hydrocarbons from the subterranean
formation at
320. Methods 300 additionally may include repeating the methods at 325.
[0097] It is within the scope of the present disclosure that the
converting at 310 may form
a portion of a subsequent production-enhancing process that is configured to
be performed
within the subterranean formation after performing an initial production-
enhancing process.
Under these conditions, performing the initial production-enhancing process at
305 may
include performing any suitable process and/or operation within the
subterranean formation
to decrease the viscosity of the viscous hydrocarbons that are contained
therein and/or to
produce the viscous hydrocarbons therefrom.
[0098] As illustrative, non-exclusive examples, and as discussed, the
initial production-
enhancing processes may include one or more of in situ combustion, a cyclic
solvent process,
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cyclic steam injection, steam assisted gravity drainage, solvent assisted
gravity drainage,
solvent assisted steam assisted gravity drainage, steatnflood, heated solvent,
non-heated
vapor extraction, and/or heated vapor extraction. It is within the scope of
the present
disclosure that performing the initial production-enhancing process at 305 may
include
removing and/or depleting the viscous hydrocarbons from a region, or portion,
of the
subterranean formation, such as from a heated zone that may be utilized during
the
converting at 310.
[0099] It is also within the scope of the present disclosure that methods
300 further may
include depressurizing, or blowing down, the subterranean formation and/or an
injection well
that extends therein. As an illustrative, non-exclusive example, the
depressurizing may
include depressurizing the injection well after performing the initial
production-enhancing
process and prior to performing the subsequent production-enhancing process.
As another
illustrative, non-exclusive example, the depressurizing may include
depressurizing the
injection well subsequent to performing both the initial production-enhancing
process and the
subsequent production-enhancing process.
[0100] Converting the viscous hydrocarbons to heated and diluted
hydrocarbons at 310
may include performing any suitable production-enhancing process to both heat
and dilute
the viscous hydrocarbons that are present within the subterranean formation.
As an
illustrative, non-exclusive example, the converting at 310 may include
performing any of the
methods 200 that are disclosed herein and discussed in more detail with
reference to Fig. 5.
[0101] It is within the scope of the present disclosure that the
converting at 310 may form
a portion of an initial production-enhancing process that is configured to be
performed within
the subterranean formation prior to performing a subsequent production-
enhancing process.
Under these conditions, performing the subsequent production-enhancing process
at 315 may
include performing any suitable process and/or operation within the
subterranean formation
to decrease the viscosity of the viscous hydrocarbons that are contained
therein and/or to
produce the viscous hydrocarbons therefrom. Illustrative, non-exclusive
examples of
subsequent production-enhancing processes include any of the initial
production-enhancing
processes that are discussed in more detail herein with reference to
performing the initial
production-enhancing process at 305.
[0102] Producing the heated and diluted hydrocarbons from the
subterranean formation at
320 may include the use of any suitable systems and/or methods to remove the
heated and
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diluted hydrocarbons from the subterranean formation and/or to convey the
heated and
diluted hydrocarbons to a surface region, and may be at least substantially
similar to the
producing at 245 that is discussed in more detail herein with reference to
Fig. 5. It is within
the scope of the present disclosure that the producing at 320 may be
intermittent or
continuous. As an illustrative, non-exclusive example, and when a single
wellbore is utilized
during the converting at 310 (such as for supply of the dual-duty agent and
the oxidant to the
subterranean formation) and the producing at 320 (such as to convey the heated
and diluted
hydrocarbons from the subterranean formation and to the surface region), the
producing at
320 may be performed intermittently and/or subsequent to the converting at
310. As another
illustrative, non-exclusive example, and when an injection well is utilized
during the
converting at 310 (such as for supply of the dual-duty agent and the oxidant
to the
subterranean formation) and a separate production well is utilized during the
producing at
320 (such as to convey the heated and diluted hydrocarbons from the
subterranean formation
and to the surface region), the producing at 320 may be performed
continuously, at least
substantially continuously, and/or during the converting at 310.
[0103] It is also within the scope of the present disclosure that the
producing at 320 may
be performed any suitable number of times and/or in any suitable sequence
during methods
300. As an illustrative, non-exclusive example, and when methods 300 include
both the
performing at 305 and the converting at 310, the producing at 320 may be
performed both
subsequent to the performing at 305 and subsequent to the converting at 310.
Alternatively,
the producing at 320 may be performed subsequent to the converting at 310 but
not
subsequent to the performing at 305. As another illustrative, non-exclusive
example, and
when methods 300 include the converting at 310 and the performing at 315, the
producing at
320 may be performed both subsequent to the converting at 310 and subsequent
to the
performing at 315. Alternatively, the producing at 320 may be performed
subsequent to the
performing at 315 but not subsequent to the converting at 310.
[0104] Repeating the method at 325 may include repeating any suitable
portion of the
method based on any suitable criteria. As an illustrative, non-exclusive
example, and when
methods 300 include the performing at 305, the repeating at 325 may include
repeating the
performing at 305 a plurality of times prior to the converting at 310; and an
illustrative, non-
exclusive example of this repeating is discussed in more detail herein with
reference to Fig. 4.
Additionally or alternatively, the repeating at 325 also may include repeating
the converting
at 310 a plurality of times subsequent to the performing at 305 and/or
repeating the
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performing at 305 one or more times subsequent to the converting at 310.
[0105] Alternatively, and when methods 300 include the performing at 315,
the repeating
at 325 also may include repeating the converting at 310 a plurality of times
prior to the
performing at 315 and/or repeating the performing at 315 a plurality of times
subsequent to
the converting at 310. Additionally or alternatively, the repeating at 325
also may include
repeating the converting at 310 one or more times subsequent to the performing
at 315.
[0106] As discussed, the producing at 320 may be performed any suitable
number of
times and/or in any suitable sequence during methods 300. Thus, the repeating
at 325 further
may include repeating the producing at 320, such as by performing the
producing subsequent
to the performing at 305, subsequent to the converting at 310, and/or
subsequent to the
performing at 315.
[0107] In the present disclosure, several of the illustrative, non-
exclusive examples have
been discussed and/or presented in the context of flow diagrams, or flow
charts, in which the
methods are shown and described as a series of blocks, or steps. Unless
specifically set forth
in the accompanying description, it is within the scope of the present
disclosure that the order
of the blocks may vary from the illustrated order in the flow diagram,
including with two or
more of the blocks (or steps) occurring in a different order and/or
concurrently. It is also
within the scope of the present disclosure that the blocks, or steps, may be
implemented as
logic, which also may be described as implementing the blocks, or steps, as
logics. In some
applications, the blocks, or steps, may represent expressions and/or actions
to be performed
by functionally equivalent circuits or other logic devices. The illustrated
blocks may, but are
not required to, represent executable instructions that cause a computer,
processor, and/or
other logic device to respond, to perform an action, to change states, to
generate an output or
display, and/or to make decisions.
[0108] As used herein, the term "and/or placed between a first entity and a
second entity
means one of (1) the first entity, (2) the second entity, and (3) the first
entity and the second
entity. Multiple entities listed with "and/or should be construed in the same
manner, i.e.,
"one or more" of the entities so conjoined. Other entities may optionally be
present other
than the entities specifically identified by the "and/or" clause, whether
related or unrelated to
those entities specifically identified. Thus, as a non-limiting example, a
reference to "A
and/or B," when used in conjunction with open-ended language such as
"comprising" may
refer, in one embodiment, to A only (optionally including entities other than
B); in another
28
embodiment, to B only (optionally including entities other than A); in yet
another
embodiment, to both A and B (optionally including other entities). These
entities may refer
to elements, actions, structures, steps, operations, values, and the like.
[0109] As used herein, the phrase "at least one," in reference to a
list of one or more
entities should be understood to mean at least one entity selected from any
one or more of the
entity in the list of entities, but not necessarily including at least one of
each and every entity
specifically listed within the list of entities and not excluding any
combinations of entities in
the list of entities. This definition also allows that entities may optionally
be present other
than the entities specifically identified within the list of entities to which
the phrase "at least
one" refers, whether related or unrelated to those entities specifically
identified. Thus, as a
non-limiting example, "at least one of A and B" (or, equivalently, "at least
one of A or B," or,
equivalently "at least one of A and/or B") may refer, in one embodiment, to at
least one,
optionally including more than one, A, with no B present (and optionally
including entities
other than B); in another embodiment, to at least one, optionally including
more than one, B,
with no A present (and optionally including entities other than A); in yet
another
embodiment, to at least one, optionally including more than one, A, and at
least one,
optionally including more than one, B (and optionally including other
entities). In other
words, the phrases "at least one," "one or more," and "and/or" are open-ended
expressions
that are both conjunctive and disjunctive in operation. For example, each of
the expressions
"at least one of A, B and C," "at least one of A, B, or C," "one or more of A,
B, and C," "one
or more of A, B, or C" and "A, B, and/or C" may mean A alone, B alone, C
alone, A and B
together, A and C together, B and C together, A, B and C together, and
optionally any of the
above in combination with at least one other entity.
[0110]
[0111] As used herein the terms "adapted" and "configured" mean that the
element,
component, or other subject matter is designed and/or intended to perform a
given function.
Thus, the use of the terms "adapted" and "configured" should not be construed
to mean that a
29
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given element, component, or other subject matter is simply "capable of"
performing a given
function but that the element, component, and/or other subject matter is
specifically selected,
created, implemented, utilized, programmed, and/or designed for the purpose of
performing
the function. It is also within the scope of the present disclosure that
elements, components,
and/or other recited subject matter that is recited as being adapted to
perform a particular
function may additionally or alternatively be described as being configured to
perform that
function, and vice versa.
[0112]
Illustrative, non-exclusive examples of systems and methods according to the
present disclosure are presented in the following enumerated paragraphs. It is
within the
scope of the present disclosure that an individual step of a method recited
herein, including in
the following enumerated paragraphs, may additionally or alternatively be
referred to as a
"step for" performing the recited action.
[0113] Al. A
method of heating and diluting viscous hydrocarbons within a subterranean
formation, the method comprising:
supplying a dual-duty agent to the subterranean formation;
supplying an oxidant to the subterranean formation;
combusting a combusted portion of the dual-duty agent with the oxidant to heat
a
portion of the subterranean formation, with this portion of the subterranean
formation
forming a heated zone of the subterranean formation;
ceasing the supplying of the oxidant while continuing the supplying of the
dual-duty
agent to the subterranean formation;
flowing an uncombusted portion of the dual-duty agent through the heated zone
to
heat the uncombusted portion of the dual-duty agent and generate a heated dual-
duty agent;
and
contacting the viscous hydrocarbons with the heated dual-duty agent to
generate
heated and diluted hydrocarbons.
[0114] A2. The
method of paragraph Al, wherein the supplying the dual-duty agent
includes continuously supplying the dual-duty agent.
[0115] A3. The
method of paragraph Al, wherein the supplying the dual-duty agent
includes periodically supplying the dual-duty agent.
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[0116] A4. The method of any of paragraphs Al-A3, wherein the supplying
the oxidant
includes periodically supplying the oxidant.
[0117] Bl. A method of heating and diluting viscous hydrocarbons within a
subterranean
formation, the method comprising:
continuously supplying a dual-duty agent to the subterranean formation;
periodically supplying an oxidant to the subterranean formation;
combusting a combusted portion with the oxidant of the dual-duty agent in a
heated
zone of the subterranean formation during the periodically supplying;
flowing an uncombusted portion of the dual-duty agent through the heated zone
to
heat the uncombusted portion of the dual-duty agent and generate a heated dual-
duty agent;
and
contacting the viscous hydrocarbons with the heated dual-duty agent to
generate
heated and diluted hydrocarbons.
[0118] B2. The method of paragraph Bl, wherein the periodically supplying
the oxidant
includes ceasing the supplying of the oxidant while continuing the supplying
of the dual-duty
agent to the subterranean formation.
[0119] Cl. The method of any of paragraphs A 1 -B2, wherein, prior to
supplying the
dual-duty agent, the method further includes pre-heating the dual-duty agent.
[0120] C2. The method of paragraph Cl, wherein the pre-heating includes
pre-heating
the dual-duty agent within a surface region, and optionally wherein the
surface region is
proximate to a wellbore that extends within the subterranean formation.
[0121] C3. The method of any of paragraphs Al -C2, wherein the method
further
includes producing the heated and diluted hydrocarbons from the subterranean
formation.
[0122] C4. The method of paragraph C3, wherein the producing includes
producing
from a production well that extends within the subterranean formation.
[0123] C5. The method of any of paragraphs C3-C4, wherein the combusting
includes
producing a gaseous combustion product and pressurizing the subterranean
formation with
the gaseous combustion product to provide a motive force for the producing.
[0124] C6. The method of any of paragraphs C3-05, wherein the producing
further
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includes producing the heated and diluted hydrocarbons from the subterranean
formation
without supplying a supplemental dual-duty agent to the subterranean
formation.
[0125] C7. The method of any of paragraphs C4-C6, wherein the
(continuously)
supplying the dual-duty agent and the (periodically) supplying the oxidant
include supplying
the dual-duty agent and the oxidant to the production well.
[0126] C8. The method of paragraph C7, wherein at least one of the
(continuously)
supplying the dual-duty agent and the (periodically) supplying the oxidant
includes supplying
the at least one of the dual-duty agent and the oxidant to the production well
via an auxiliary
well that intersects the production well, and optionally wherein the method
further includes
venting a combustion product stream from the production well via the auxiliary
well.
[0127] C9. The method of any of paragraphs C4-C6, wherein the
(continuously)
supplying the dual-duty agent and the (periodically) supplying the oxidant
includes supplying
the dual-duty agent and the oxidant to an injection well that is separate from
the production
well.
[0128] C I O. The method of paragraph C9, wherein the combusting includes
at least one
of combusting within the simulation well and combusting within a portion of
the
subterranean formation that is adjacent to the injection well.
[0129] Cl 1 . The method of any of paragraphs C9-C10, wherein the
injection well is at
least one of adjacent to at least a portion of the production well, parallel
to at least a portion
.. of the production well, and located vertically above at least a portion of
the production well.
[0130] C12. The method of any of paragraphs Al-C1 1, wherein the
(continuously)
supplying the dual-duty agent, the (periodically) supplying the oxidant, and
the combusting
include supplying the dual-duty agent and the oxidant to a/the wellbore that
extends within
the subterranean formation and combusting a combustible mixture that includes
the dual-duty
agent and the oxidant.
[0131] C13. The method of paragraph C12, wherein the combusting includes
combusting
within the wellbore.
[0132] C14. The method of any of paragraphs C12-C13, wherein the
combusting
includes combusting within a portion of the subterranean formation that is
proximal to the
wellbore.
[0133] C15. The method of paragraph C14, wherein a majority of the
viscous
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hydrocarbons are removed from the portion of the subterranean formation prior
to the
combusting, and optionally wherein the method further includes removing the
majority of the
viscous hydrocarbons from the portion of the subterranean formation prior to
the combusting.
[0134] C16. The method of any of paragraphs A 1 -C 15, wherein the
(continuously)
supplying the dual-duty agent includes supplying the dual-duty agent to the
subterranean
formation as a liquid dual-duty agent, and optionally wherein the method
further includes
vaporizing the dual-duty agent within the subterranean formation to generate a
vaporous
dual-duty agent.
[0135] C17. The method of any of paragraphs A1-C16, wherein the
(continuously)
supplying the dual-duty agent includes supplying the dual-duty agent to the
subterranean
formation as at least one of a gas and a vapor.
[0136] C18. The method of any of paragraphs AI-C17, wherein the method
further
includes mixing the oxidant with the dual-duty agent within at least one of
a/the wellbore, the
subterranean formation, and the heated zone to form a/the combustible mixture.
[0137] C19. The method of paragraph C18, wherein the method further
includes igniting
the combustible mixture within the heated zone, optionally wherein the
igniting includes
actuating an ignition source that is present within the heated zone.
[0138] C20. The method of any of paragraphs A 1 -C19, wherein the
(periodically)
supplying the oxidant and the combusting are initiated based, at least in
part, on an elapsed
time since a prior (periodically) supplying the oxidant.
[0139] C21. The method of any of paragraphs Al-C20, wherein the
(periodically)
supplying the oxidant and the combusting arc initiated based, at least in
part, on a
temperature of the heated zone, optionally wherein the (periodically)
supplying and the
combusting are initiated to maintain the temperature of the heated zone above
a threshold
lower heated zone temperature, and further optionally wherein the threshold
lower heated
zone temperature is greater than 15 C, greater than 20 C, greater than 25
C, greater than 30
C, greater than 35 C, greater than 40 C, greater than 50 C, greater than 60
C, greater than
70 C, greater than 80 C, or greater than 90 C.
[0140] C22. The method of any of paragraphs A 1-C21, wherein the
(periodically)
supplying the oxidant and the combusting are initiated based, at least in
part, on a property of
the heated and diluted hydrocarbons.
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[0141] C23. The method of paragraph C22, wherein the property of the
heated and
diluted hydrocarbons includes a temperature of the heated and diluted
hydrocarbons,
optionally wherein the temperature of the heated and diluted hydrocarbons is
measured
within the subterranean formation, optionally wherein the temperature of the
heated and
diluted hydrocarbons is measured within a/the surface region, optionally
wherein the
(periodically) supplying and the combusting are initiated to maintain the
temperature of the
heated and diluted hydrocarbons above a threshold lower hydrocarbon
temperature, and
further optionally wherein the threshold lower hydrocarbon temperature is
greater than 15 C,
greater than 20 C, greater than 25 C, greater than 30 C, greater than 35
C, greater than 40
C, greater than 50 C, greater than 60 C, greater than 70 C, greater than 80
C, or greater
than 90 C.
[0142] C24. The method of any of paragraphs C22-C23, wherein the property
of the
heated and diluted hydrocarbons includes a viscosity of the heated and diluted
hydrocarbons,
optionally wherein the viscosity of the heated and diluted hydrocarbons is
measured within
the subterranean formation, optionally wherein the viscosity of the heated and
diluted
hydrocarbons is measured in a/the surface region, optionally wherein the
(periodically)
supplying and the combusting are initiated to maintain the viscosity of the
heated and diluted
hydrocarbons below a threshold viscosity, and further optionally wherein the
threshold
viscosity is less than 5000 cP, less than 4500 cP, less than 4000 cP, less
than 3500 cP, less
than 3000 cP, less than 2500 cP, less than 2000 cP, less than 1500 cP, or less
than 1000 cP.
[0143] C25. The method of any of paragraphs A1-C24, wherein the
combusting includes
combusting a fuel stream that includes the combusted portion of the dual-duty
agent and a
portion of the viscous hydrocarbons.
[0144] C26. The method of paragraph C25, wherein the dual-duty agent
comprises at
least 60 wt%, at least 65 wt%, at least 70 wt%, at least 75 wt%, at least 80
wt%, at least 85
wt%, at least 90 wt%, at least 95 wt%, at least 96 wt%, at least 97 wt%, at
least 98 wt%, or at
least 99 wt% of the fuel stream.
[0145] C27. The method of any of paragraphs C25-C26, wherein the viscous
hydrocarbons comprise less than 40 wt%, less than 35 wt%, less than 30 wt%,
less than 25
wt%, less than 20 wt%, less than 15 wt%, less than 10 wt%, less than 5 wt%,
less than 4 wt%,
less than 3 wt%. less than 2 wt%, or less than 1 wt% of the fuel stream.
[0146] C28. The method of any of paragraphs A1-C27, wherein a/the ceasing
the
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supplying of the oxidant includes at least one of ceasing the combusting and
initiating ceasing
of the combusting.
[0147] C29. The method of any of paragraphs Al-C28, wherein a/the ceasing
the
supplying of the oxidant includes ceasing the supplying of the oxidant based,
at least in part,
on an elapsed time since a start of the (periodically) supplying the oxidant.
[0148] C30. The method of any of paragraphs A 1 -C29, wherein a/the
ceasing the
supplying of the oxidant includes ceasing the supplying of the oxidant based,
at least in part,
on a/the temperature of the heated zone, optionally wherein the ceasing the
supplying
includes ceasing the supplying to maintain the temperature of the heated zone
below a
threshold upper heated zone temperature, and further optionally wherein the
threshold upper
heated zone temperature includes a temperature of less than 900 C, less than
850 C, less
than 825 C, less than 800 C, less than 775 C, less than 750 C, less than
725 C, less than
700 C, less than 675 C, less than 650 C, less than 600 C, less than 550
C, or less than
500 C.
[0149] C31. The method of any of paragraphs AI -C30, wherein a/the ceasing
the
supplying of the oxidant includes ceasing the supplying of the oxidant based,
at least in part,
on a/the property of the heated and diluted hydrocarbons.
[0150] C32. The method of paragraph C31, wherein the property of the
heated and
diluted hydrocarbons includes a/the temperature of the heated and diluted
hydrocarbons,
optionally wherein the temperature of the heated and diluted hydrocarbons is
measured
within the subterranean formation, optionally wherein the temperature of the
heated and
diluted hydrocarbons is measured within a/the surface region, optionally
wherein the ceasing
the supplying of the oxidant includes ceasing the supplying of the oxidant to
maintain the
temperature of the heated and diluted hydrocarbons below a threshold upper
hydrocarbon
temperature, and further optionally wherein the threshold upper hydrocarbon
temperature is
less than 500 C, less than 450 C, less than 400 C, less than 375 C, less
than 350 C, less
than 325 C, less than 300 C, less than 250 C, or less than 200 C.
[0151] C33. The method of any of paragraphs Al-C32, wherein the
(continuously)
supplying the dual-duty agent to the subterranean formation includes supplying
a
predetermined volume of the dual-duty agent to the subterranean formation.
[0152] C34. The method of paragraph C33, wherein a/the ceasing the
supplying of the
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oxidant includes ceasing the supplying of the oxidant responsive to combusting
a fraction of
the predetermined volume of the dual-duty agent, optionally wherein the
fraction is at least
0.5 volume %, at least 1 volume %, at least 2 volume %, at least 3 volume %,
at least 4
volume %, at least 5 volume %, at least 6 volume %, at least 7 volume %, at
least 8 volume
%, at least 9 volume %, at least 10 volume %, or at least 15 volume % of the
predetermined
volume of the dual-duty agent, and further optionally wherein the fraction is
less than 30
volume %, less than 25 volume %, less than 22.5 volume %. less than 20 volume
%, less than
17.5 volume %, less than 15 volume %, less than 12.5 volume %, less than 10
volume %, less
than 7.5 volume %, or less than 5 volume % of the predetermined volume of the
dual-duty
agent.
[0153] C35. The method of any of paragraphs Al -C34, wherein the flowing
the
uncombusted portion of the dual-duty agent through the heated zone includes
thermally
contacting the uncombusted portion of the dual-duty agent with the heated
zone, and
optionally with reservoir solids that are present within the heated zone.
[0154] C36. The method of any of paragraphs Al-C35. wherein the flowing the
uncombusted portion of the dual-duty agent through the heated zone includes
transferring
thermal energy from the heated zone, and optionally from a/the reservoir
solids that are
present within the heated zone, to the dual-duty agent to generate the heated
dual-duty agent.
[0155] C37. The method of any of paragraphs A 1 -C36, wherein the
contacting the
viscous hydrocarbons with the heated dual-duty agent includes at least one,
and optionally
both, of thermally contacting the viscous hydrocarbons with the heated dual-
duty agent and
physically contacting the viscous hydrocarbons with the heated dual-duty
agent.
[0156] C38. The method of any of paragraphs Al-C37, wherein the
contacting the
viscous hydrocarbons with the heated dual-duty agent includes at least one of
absorbing the
heated dual-duty agent within the viscous hydrocarbons and mixing the heated
dual-duty
agent with the viscous hydrocarbons.
[0157] C39. The method of any of paragraphs Al-C38, wherein the
contacting the
viscous hydrocarbons with the heated dual-duty agent includes at least one of
diluting the
viscous hydrocarbons with the heated dual-duty agent and forming a mixture of
the heated
dual-duty agent and the viscous hydrocarbons.
[0158] C40. The method of any of paragraphs A 1-C39, wherein the method
further
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includes generating the heated and diluted hydrocarbons without generating two
separate
liquid hydrocarbon phases that include the viscous hydrocarbons within the
subterranean
formation.
[0159] C41. The method of any of paragraphs AI-C39, wherein the method
further
includes generating a heavy liquid hydrocarbon phase that includes a portion
of the viscous
hydrocarbons and a light liquid hydrocarbon phase that includes a portion of
the viscous
hydrocarbons within the subterranean formation, and further wherein a volume
of the
generated heavy liquid hydrocarbon phase is less than 25%, less than 20%, less
than 15%,
less than 10%, less than 5%, less than 2.5%, or less than 1% of a volume of
the generated
light liquid hydrocarbon phase.
[0160] C42. The method of any of paragraphs A1-C41, wherein the
combusting includes
generating a/the gaseous combustion product, and further wherein the method
includes
retaining the gaseous combustion product within the subterranean formation.
[0161] C43. The method of any of paragraphs Al -C42, wherein the method
further
includes producing the heated and diluted hydrocarbons without supplying a/the
supplemental diluent to the subterranean formation.
[0162] C44. The method of any of paragraphs Al -C43, wherein the method
further
includes producing the heated and diluted hydrocarbons without supplying steam
to the
subterranean formation.
[0163] C45. The method of any of paragraphs Al -C44, wherein the method
further
includes producing the heated and diluted hydrocarbons without utilizing the
viscous
hydrocarbons as a primary fuel for the combusting.
[0164] C46. The method of any of paragraphs A1-C45, wherein the dual-duty
agent
includes a flammable material.
[0165] C47. The method of any of paragraphs Al -C46, wherein the dual-duty
agent
includes a material that at least one of dilutes the viscous hydrocarbons, is
soluble in the
viscous hydrocarbons, dissolves the viscous hydrocarbons, decreases a/the
viscosity of the
viscous hydrocarbons, and is miscible in the viscous hydrocarbons.
[0166] C48. The method of any of paragraphs Al -C47, wherein the dual-
duty agent
includes at least one of a diluent and a solvent for at least a portion of the
viscous
hydrocarbons.
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[0167] C49.
The method of any of paragraphs AI -C48, wherein the dual-duty agent
includes at least one of methane, ethane, propane, butane, pentane, hexane,
heptane, octane,
nonane, decane, dimethyl ether, an alkane, naphtha, natural gas condensate,
gas plant
condensate, and mixtures of the above.
[0168] C50. The method
of any of paragraphs Al-C49, wherein the viscous
hydrocarbons include at least one of bitumen, tar, an unconventional
hydrocarbon reserve,
and a hydrocarbon with a viscosity that is too high to be produced from the
subterranean
formation using primary hydrocarbon recovery operations and secondary
hydrocarbon
recovery operations.
[0169] C51. The method of any of paragraphs Al-050, wherein the
subterranean
formation includes at least one of an oil sands formation, a tar sands
formation, and a
bituminous sands formation.
[0170] C52.
The method of any of paragraphs Al-051, wherein the oxidant includes at
least one of oxygen, air, oxygen-enriched air, and a chemical oxidant.
[0171] C53. The method of any of paragraphs Al-052, wherein the heated and
diluted
hydrocarbons have a temperature that is at least one of:
(i) greater than an ambient temperature within the subterranean formation
prior to
the combusting;
(ii) greater than a temperature of the viscous hydrocarbons prior to the
contacting;
and
(iii) at least 15 C, at least 20 C, at least 25 C, at least 30 C, at
least 35 C, at
least 40 C, at least 45 C, at least 50 C, at least 55 C, at least 60 C,
at least 65 C, at least
70 C, at least 75 C, at least 80 C, at least 85 C, at least 90 C, at
least 95 C, or at least
100 C.
[0172] C54. The method of any of paragraphs Al-053, wherein the heated and
diluted
hydrocarbons have a viscosity that is at least 2, at least 3, at least 4, at
least 5, at least 10, at
least 25, at least 50, at least 100, at least 250, at least 500, at least 750,
or at least 1000 times
lower than at least one of:
(i) an
average viscosity of the viscous hydrocarbons prior to the combusting; and
(ii) an average viscosity of the viscous hydrocarbons prior to the
contacting.
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[0173] C55. The method of any of paragraphs A 1 -054, wherein the heated
and diluted
hydrocarbons include a mixture of the viscous hydrocarbons and the uncombusted
portion of
the dual-duty agent, and optionally wherein the heated and diluted
hydrocarbons further
include gaseous combustion products from the combusting.
[0174] C56. The method of any of paragraphs Al-055, wherein the heated zone
includes
a portion of a/the wellbore that extends within the subterranean formation.
[0175] C57. The method of any of paragraphs A1-056. wherein the heated
zone includes
a portion of the subterranean formation where the combusting occurs.
[0176] C58. The method of any of paragraphs A1-057, wherein the heated
zone includes
reservoir solids that are heated by the combusting.
[0177] C59. The method of any of paragraphs A1-058, wherein the method
further
includes repeating the method, optionally wherein the repeating includes
repeating at least the
(periodically) supplying the oxidant and the combusting subsequent to the
flowing and the
contacting.
[0178] Dl. A method of enhancing production of viscous hydrocarbons from a
subterranean formation, the method comprising:
converting the viscous hydrocarbons to heated and diluted hydrocarbons using
the
method of any of paragraphs Al-059; and
producing the heated and diluted hydrocarbons from the subterranean formation.
[0179] D2. The method of paragraph Dl, wherein, subsequent to the
converting, the
method further includes performing a cyclic solvent process to produce a
portion of the
viscous hydrocarbons from the subterranean formation.
[0180] D3. The method of paragraph D2, wherein the method further
includes repeating
the cyclic solvent process a plurality of times subsequent to the converting.
[0181] D4. The method of paragraph D1, wherein the converting forms a
portion of an
initial production-enhancing process, and further wherein, subsequent to the
converting, the
method further includes performing a subsequent production-enhancing process.
[0182] D5. The method of paragraph D4, wherein the subsequent production-
enhancing
process includes a cyclic solvent process.
[0183] D6. The method of paragraph D4, wherein the subsequent production-
enhancing
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process includes at least one of in situ combustion, a cyclic solvent process,
cyclic steam
stimulation, steam assisted gravity drainage, solvent assisted steam assisted
gravity drainage,
solvent assisted gravity drainage, steamflood, heated solvent, non-heated
vapor extraction,
and heated vapor extraction.
[0184] D7. The method of any one of paragraphs D1-D6, wherein the
converting forms a
portion of a subsequent production-enhancing process, and further wherein,
prior to the
converting, the method further includes performing an initial production-
enhancing process,
and optionally wherein the method further includes depressurizing a/the
injection well that
extends within the subterranean formation after performing the initial
production-enhancing
process and prior to performing the subsequent production-enhancing process.
[0185] D8. The method of paragraph D7, wherein the initial production-
enhancing
process includes a cyclic solvent process.
[0186] D9. The method of paragraph D7, wherein the initial production-
enhancing
process includes at least one of in situ combustion, a cyclic solvent process,
cyclic steam
stimulation, steam assisted gravity drainage, solvent assisted steam assisted
gravity drainage,
solvent assisted gravity drainage, steamflood, heated solvent, non-heated
vapor extraction,
and heated vapor extraction.
[0187] D10. The method of any of paragraphs D4-D9, wherein the method
further
includes repeating the initial production-enhancing process a plurality of
times prior to
performing the subsequent production-enhancing process.
[0188] D11. The method of any of paragraphs D4-D10, wherein the method
further
includes repeating the subsequent production-enhancing process a plurality of
times
subsequent to performing the initial production-enhancing process.
[0189] D12. The method of any of paragraphs D4-D11, wherein the method
further
includes repeating the initial production-enhancing process subsequent to
performing the
subsequent production-enhancing process, and optionally wherein the method
further
includes repeating the subsequent production-enhancing process subsequent to
repeating the
initial production-enhancing process.
[0190] D13. The method of any of paragraphs D4-D12, wherein the method
further
includes repeating the initial production-enhancing process a plurality of
times.
[0191] D14. The method of any of paragraphs D4-D13, wherein the method
further
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includes repeating the subsequent production-enhancing process a plurality of
times.
[0192] D15. The method of any of paragraphs DJ-D14, wherein the method
includes
ceasing the converting during the producing.
[0193] D16. The method of paragraph D15, wherein the converting includes
conveying
the dual-duty agent through a/the wellbore that extends within the
subterranean formation,
and further wherein the producing includes producing the heated and diluted
hydrocarbons
from the wellbore.
[0194] D17. The method of any of paragraphs DI-D14, wherein the method
includes
continuing the converting during the producing.
[0195] D18. The method of paragraph D17, wherein the converting includes
conveying
the dual-duty agent through a/the injection well that extends within the
subterranean
formation, and further wherein the producing includes producing the heated and
diluted
hydrocarbons from a production well that is separate from the injection well.
[0196] D19. The method of any of paragraphs D1 -D18, wherein the method
further
includes repeating the method.
[0197] El. A viscous hydrocarbon production assembly, comprising:
a wellbore that extends between a surface region and a subterranean formation
that
includes a viscous hydrocarbon;
a dual-duty agent supply system that is configured to selectively supply a
dual-duty
agent through the wellbore to the subterranean formation;
an oxidant supply system that is configured to selectively supply an oxidant
through
the wellbore to the subterranean formation; and
a controller that is programmed to control the operation of the viscous
hydrocarbon
production assembly using the method of any of paragraphs Al-D19.
[0198] E2. The viscous hydrocarbon production assembly of paragraph El,
wherein the
assembly further includes a heated and diluted hydrocarbon production system
that is
configured to produce a heated and diluted hydrocarbon stream that includes
heated and
diluted hydrocarbons from the subterranean formation.
[0199] E3. The viscous hydrocarbon production assembly of paragraph E2,
wherein the
heated and diluted hydrocarbon production system is configured to produce the
heated and
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diluted hydrocarbon stream from the wellbore.
[0200] E4. The viscous hydrocarbon production assembly of paragraph E2,
wherein the
wellbore forms a portion of an injection well, wherein the assembly further
includes a
production well that extends between the surface region and the subterranean
formation, and
further wherein the injection well is separate from the production well.
[0201] E5. The viscous hydrocarbon production assembly of paragraph E4,
wherein the
heated and diluted hydrocarbon production system is configured to produce the
heated and
diluted hydrocarbon stream from the production well.
[0202] E6. The viscous hydrocarbon production assembly of any of
paragraphs E4-E5,
wherein at least a parallel portion of the injection well is parallel to at
least a parallel portion
of the production well.
[0203] E7. The viscous hydrocarbon production assembly of paragraph E6,
wherein the
parallel portion of the injection well is located vertically above the
parallel portion of the
production well.
[0204] E8. The viscous hydrocarbon production assembly of any of paragraphs
El -E7,
wherein the wellbore includes at least one of a vertical portion and a
deviated portion.
[0205] E9. The viscous hydrocarbon production assembly of any of
paragraphs El -E8,
wherein the wellbore includes a horizontal portion, optionally wherein the
horizontal portion
extends within the subterranean formation.
[0206] Fl. The use of any of the methods of any of paragraphs Al-D19 with
any of the
assemblies of any of paragraphs E I -E9.
[0207] F2. The use of any of the assemblies of any of paragraphs El-E9
with any of the
methods of any of paragraphs Al-D19.
[0208] F3. The use of any of the methods of any of paragraphs Al-A15 or
any of the
assemblies of any of paragraphs El -E9 to generate heated and diluted
hydrocarbons.
[0209] F4. The use of any of the methods of any of paragraphs Al-Al 5 or
any of the
assemblies of any of paragraphs El-E9 to stimulate a subterranean formation
that includes
viscous hydrocarbons.
[0210] F5. The use of any of the methods of any of paragraphs Al -Al 5 or
any of the
assemblies of any of paragraphs El-E9 to heat and dilute viscous hydrocarbons
that are
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present within a subterranean formation.
[0211] Fb. The use of any of the methods of any of paragraphs Al -A15 or
any of the
assemblies of any of paragraphs El-E9 to produce viscous hydrocarbons from a
subterranean
formation.
[0212] F7. The use of a dual-duty agent to heat and dilute viscous
hydrocarbons that are
present within a subterranean formation.
[0213] F8. The use of a dual-duty agent to stimulate production of
viscous hydrocarbons
from a subterranean formation.
[0214] PCT1. A method of heating and diluting viscous hydrocarbons within
a
subterranean formation, the method comprising:
supplying a dual-duty agent to the subterranean formation;
supplying an oxidant to the subterranean formation;
combusting a combusted portion of the dual-duty agent with the oxidant to heat
a
portion of the subterranean formation, with this portion of the subterranean
formation
.. forming a heated zone of the subterranean formation;
ceasing the supplying of the oxidant while continuing the supplying of the
dual-duty
agent to the subterranean formation;
flowing an uncombusted portion of the dual-duty agent through the heated zone
to
heat the uncombusted portion of the dual-duty agent and generate a heated dual-
duty agent;
and
contacting the viscous hydrocarbons with the heated dual-duty agent to
generate
heated and diluted hydrocarbons.
[0215] PCT2. The method of paragraph PCT1, wherein the method further
includes
producing the heated and diluted hydrocarbons from the subterranean formation,
wherein the
producing includes producing from a production well that extends within the
subterranean
formation, and further wherein the supplying the dual-duty agent and the
supplying the
oxidant include supplying the dual-duty agent and the oxidant to the
production well.
[0216] PCT3. The method of paragraph PCT I, wherein the method further
includes
producing the heated and diluted hydrocarbons from the subterranean formation,
wherein the
producing includes producing from a production well that extends within the
subterranean
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formation, and further wherein the supplying the dual-duty agent and the
supplying the
oxidant includes supplying the dual-duty agent and the oxidant to an injection
well that is
separate from the production well.
[0217] PCT4. The method of any of paragraphs PCT2-PCT3, wherein the
combusting
includes producing a gaseous combustion product and pressurizing the
subterranean
formation with the gaseous combustion product to provide a motive force for
the producing.
[0218] PCT5. The method of any of paragraphs PCT1-PCT4, wherein the
method further
includes mixing the oxidant with the dual-duty agent within at least one of a
wellbore that
extends within the subterranean formation, the subterranean formation, and the
heated zone to
form a combustible mixture, and further wherein the method includes igniting
the
combustible mixture within the heated zone.
[0219] PCT6. The method of any of paragraphs PCT1-PCT5, wherein the
supplying the
oxidant and the combusting are initiated based, at least in part, on at least
one of a
temperature of the heated zone and a temperature of the heated and diluted
hydrocarbons,
wherein the supplying and the combusting are initiated to at least one of
maintain the
temperature of the heated zone above a threshold lower heated zone temperature
that is
greater than 25 C and maintain the temperature of the heated and diluted
hydrocarbons
above a threshold lower hydrocarbon temperature that is greater than 20 C.
[0220] PCT7. The method of any of paragraphs PCT1-PCT6, wherein the
combusting
includes combusting a fuel stream that includes the combusted portion of the
dual-duty agent
and a portion of the viscous hydrocarbons, wherein the dual-duty agent
comprises at least 80
wt% of the fuel stream, and further wherein the viscous hydrocarbons comprise
less than 20
wt% of the fuel stream.
[0221] PCT8. The method of any of paragraphs PCT1-PCT8, wherein the
ceasing the
supplying of the oxidant includes ceasing the supplying of the oxidant based,
at least in part,
on at least one of a temperature of the heated zone and a temperature of the
heated and
diluted hydrocarbons, and further wherein the ceasing the supplying includes
ceasing the
supplying to at least one of maintain the temperature of the heated zone below
a threshold
upper heated zone temperature that is less than 750 C and to maintain the
temperature of the
heated and diluted hydrocarbons below a threshold upper hydrocarbon
temperature of less
than 350 C.
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[0222] PCT9. The method of any of paragraphs PCTI -PCT8, wherein the
supplying the
dual-duty agent to the subterranean formation includes supplying a
predetermined volume of
the dual-duty agent to the subterranean formation, and further wherein the
ceasing the
supplying of the oxidant includes ceasing the supplying of the oxidant
responsive to
combusting at least 0.5 volume % and less than 20 volume % of the
predetermined volume of
the dual-duty agent.
[0223] PCT10. The method of any of paragraphs PCT1-PCT9, wherein the
contacting
the viscous hydrocarbons with the heated dual-duty agent includes mixing the
heated dual-
duty agent with the viscous hydrocarbons.
[0224] PCT11. The method of any of paragraphs PCT1-PCT10, wherein the
viscous
hydrocarbons include at least one of bitumen, tar, an unconventional
hydrocarbon reserve,
and a hydrocarbon with a viscosity that is too high to be produced from the
subterranean
formation using primary hydrocarbon recovery operations and secondary
hydrocarbon
recovery operations, and further wherein the subterranean formation includes
at least one of
an oil sands formation, a tar sands formation, and a bituminous sands
formation.
[0225] PCT12. A method of enhancing production of viscous hydrocarbons
from a
subterranean formation, the method comprising:
converting the viscous hydrocarbons to heated and diluted hydrocarbons using
the
method of any of paragraphs PCT1-PCT1 I ; and
producing the heated and diluted hydrocarbons from the subterranean formation.
[0226] PCT13. A viscous hydrocarbon production assembly, comprising:
a wellbore that extends between a surface region and a subterranean formation
that
includes a viscous hydrocarbon;
a dual-duty agent supply system that is configured to selectively supply a
dual-duty
.. agent through the wellborc and to the subterranean formation;
an oxidant supply system that is configured to selectively supply an oxidant
through
the wellbore and to the subterranean formation; and
a controller that is programmed to control the operation of the viscous
hydrocarbon
production assembly using the method of any of paragraphs PCT1-PCT12.
[0227] PCT 14. A method of heating and diluting viscous hydrocarbons within
a
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subterranean formation, the method comprising:
continuously supplying a dual-duty agent to the subterranean formation;
periodically supplying an oxidant to the subterranean formation;
combusting a combusted portion of the dual-duty agent with the oxidant in a
heated
zone of the subterranean formation during the periodically supplying;
flowing an uncombusted portion of the dual-duty agent through the heated zone
to
heat the uncombusted portion of the dual-duty agent and generate a heated dual-
duty agent;
and
contacting the viscous hydrocarbons with the heated dual-duty agent to
generate
heated and diluted hydrocarbons.
[0228] PCT15. The method of paragraph PCT14, wherein the periodically
supplying the
oxidant includes ceasing the supplying of the oxidant while continuing the
supplying of the
dual-duty agent to the subterranean formation.
[0229] US1. A method of heating and diluting viscous hydrocarbons within
a
subterranean formation, the method comprising:
supplying a dual-duty agent to the subterranean formation;
supplying an oxidant to the subterranean formation;
combusting a combusted portion of the dual-duty agent with the oxidant to heat
a
portion of the subterranean formation, with this portion of the subterranean
formation
forming a heated zone of the subterranean formation;
ceasing the supplying of the oxidant while continuing the supplying of the
dual-duty
agent to the subterranean formation;
flowing an uncombusted portion of the dual-duty agent through the heated zone
to
heat the uncom busted portion of the dual-duty agent and generate a heated
dual-duty agent;
and
contacting the viscous hydrocarbons with the heated dual-duty agent to
generate
heated and diluted hydrocarbons.
[0230] US2. The method of paragraph US1, wherein, prior to the supplying
the dual-duty
agent, the method further includes pre-heating the dual-duty agent.
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[0231] US3. The method of paragraph US1, wherein the method further
includes
producing the heated and diluted hydrocarbons from the subterranean formation.
[0232] US4. The method of paragraph US3, wherein the producing includes
producing
from a production well that extends within the subterranean formation, and
further wherein
the supplying the dual-duty agent and the supplying the oxidant include
supplying the dual-
duty agent and the oxidant to the production well.
[0233] US5. The method of paragraph US4, wherein at least one of the
supplying the
dual-duty agent and the supplying the oxidant includes supplying the at least
one of the dual-
duty agent and the oxidant to the production well via an auxiliary well that
intersects the
production well.
[0234] US6. The method of paragraph US3, wherein the producing includes
producing
from a production well that extends within the subterranean formation, and
further wherein
the supplying the dual-duty agent and the supplying the oxidant include
supplying the dual-
duty agent and the oxidant to an injection well that is separate from the
production well.
[0235] US?. The method of paragraph US3, wherein the combusting includes
producing
a gaseous combustion product and pressurizing the subterranean formation with
the gaseous
combustion product to provide a motive force for the producing.
[0236] US8. The method of paragraph US1, wherein the supplying the dual-
duty agent
includes supplying the dual-duty agent to the subterranean formation as a
liquid dual-duty
agent, and further wherein the method includes vaporizing the dual-duty agent
within the
subterranean formation to generate a vaporous dual-duty agent.
[0237] US9. The method of paragraph US I, wherein the supplying the dual-
duty agent
includes supplying the dual-duty agent to the subterranean formation as at
least one of a gas
and a vapor.
[02381 US 10. The method of paragraph US I, wherein the method further
includes
mixing the oxidant with the dual-duty agent within at least one of a wellbore
that extends
within the subterranean formation, the subterranean formation, and the heated
cone to form a
combustible mixture, and further wherein the method includes igniting the
combustible
mixture within the heated zone.
[0239] US I I. The method of paragraph US1, wherein the supplying the
oxidant and the
combusting are initiated based, at least in part, on a temperature of the
heated zone, and
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further wherein the supplying and the combusting are initiated to maintain the
temperature of
the heated zone above a threshold lower heated zone temperature that is
greater than 25 C.
[0240] US12. The method of paragraph US1, wherein the supplying the
oxidant and the
combusting are initiated based, at least in part, on a temperature of the
heated and diluted
hydrocarbons, and further wherein the supplying and the combusting are
initiated to maintain
the temperature of the heated and diluted hydrocarbons above a threshold lower
hydrocarbon
temperature that is greater than 20 C.
[0241] US13. The method of paragraph US1, wherein the supplying the
oxidant and the
combusting are initiated based, at least in part, on a viscosity of the heated
and diluted
hydrocarbons, and further wherein the supplying and the combusting are
initiated to maintain
the viscosity of the heated and diluted hydrocarbons below a threshold
viscosity that is less
than 3000 cP.
[0242] US14. The method of paragraph US1, wherein the combusting includes
combusting a fuel stream that includes the combusted portion of the dual-duty
agent and a
portion of the viscous hydrocarbons, and further wherein the dual-duty agent
comprises at
least 80 wt% of the fuel stream.
[0243] US15. The method of paragraph US14, wherein the viscous
hydrocarbons
comprise less than 20 wt% of the fuel stream.
[0244] US16. The method of paragraph US1, wherein the ceasing the
supplying of the
oxidant includes ceasing the supplying of the oxidant based, at least in part,
on a temperature
of the heated zone, and further wherein the ceasing the supplying includes
ceasing the
supplying to maintain the temperature of the heated zone below a threshold
upper heated
zone temperature that is less than 750 C.
[0245] US (7. The method of paragraph US I, wherein the ceasing the
supplying of the
oxidant includes ceasing the supplying of the oxidant based, at least in part,
on the
temperature of the heated and diluted hydrocarbons, and further wherein the
ceasing the
supplying of the oxidant includes ceasing the supplying of the oxidant to
maintain the
temperature of the heated and diluted hydrocarbons below a threshold upper
hydrocarbon
temperature of less than 350 C.
[0246] US18. The method of paragraph US I, wherein the supplying the dual-
duty agent
to the subterranean formation includes supplying a predetermined volume of the
dual-duty
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agent to the subterranean formation, and further wherein the ceasing the
supplying of the
oxidant includes ceasing the supplying of the oxidant responsive to combusting
at least 0.5
volume % and less than 15 volume % of the predetermined volume of the dual-
duty agent.
[0247] US19.
The method of paragraph US1, wherein the contacting the viscous
hydrocarbons with the heated dual-duty agent includes mixing the heated dual-
duty agent
with the viscous hydrocarbons.
[0248] US20.
The method of paragraph US1, wherein the viscous hydrocarbons include
at least one of bitumen, tar, an unconventional hydrocarbon reserve, and a
hydrocarbon with
a viscosity that is too high to be produced from the subterranean formation
using primary
hydrocarbon recovery operations and secondary hydrocarbon recovery operations,
and further
wherein the subterranean formation includes at least one of an oil sands
formation, a tar sands
formation, and a bituminous sands formation.
[0249] US21.
The method of paragraph US1, wherein the dual-duty agent includes at
least one of methane, ethane, propane, butane, pentane, hexane, heptane,
octane, nonane,
decane, dimethyl ether, an alkane, naphtha, natural gas condensate, and gas
plant condensate.
[0250] US22.
The method of paragraph US1, wherein the oxidant includes at least one of
oxygen, air, oxygen-enriched air, and a chemical oxidant.
[0251] US23. A
method of enhancing production of viscous hydrocarbons from a
subterranean formation, the method comprising:
converting the viscous hydrocarbons to heated and diluted hydrocarbons using
the
method of paragraph US1; and
producing the heated and diluted hydrocarbons from the subterranean formation.
[0252] US24.
The method of paragraph US23, wherein, subsequent to the converting, the
method further includes performing a cyclic solvent process to produce a
portion of the
viscous hydrocarbons from the subterranean formation.
[0253] US25.
The method of paragraph US23, wherein, prior to the converting, the
method further includes performing a cyclic solvent process to produce a
portion of the
viscous hydrocarbons from the subterranean formation.
[0254] U526.
The method of paragraph US23, wherein the converting forms a portion of
an initial production-enhancing process, wherein, subsequent to the
converting, the method
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further includes performing a subsequent production-enhancing process, and
further wherein
the subsequent production-enhancing process includes at least one of in situ
combustion,
cyclic steam injection, steam assisted gravity drainage, solvent assisted
steam assisted gravity
drainage, solvent assisted gravity drainage, steamflood, heated solvent, non-
heated vapor
extraction, and heated vapor extraction.
[0255] US27. The method of paragraph US23, wherein the converting forms a
portion of
a subsequent production-enhancing process, wherein, prior to the converting,
the method
further includes performing an initial production-enhancing process, and
further wherein the
initial production-enhancing process includes at least one of in situ
combustion, cyclic steam
injection, steam assisted gravity drainage, solvent assisted steam assisted
gravity drainage,
solvent assisted gravity drainage, steamflood, heated solvent, non-heated
vapor extraction,
and heated vapor extraction.
[0256] US28. A viscous hydrocarbon production assembly, comprising:
a wellbore that extends between a surface region and a subterranean formation
that
includes a viscous hydrocarbon;
a dual-duty agent supply system that is configured to selectively supply a
dual-duty
agent through the wellbore and to the subterranean formation;
an oxidant supply system that is configured to selectively supply an oxidant
through
the wellbore and to the subterranean formation; and
a controller that is programmed to control the operation of the viscous
hydrocarbon
production assembly using the method of paragraph US1.
[0257] US29. The viscous hydrocarbon production assembly of paragraph
US28,
wherein the assembly further includes a heated and diluted hydrocarbon
production system
that is configured to produce a heated and diluted hydrocarbon stream that
includes heated
and diluted hydrocarbons from the subterranean formation.
[0258] US30. The viscous hydrocarbon production assembly of paragraph
US29,
wherein the heated and diluted hydrocarbon production system is configured to
produce the
heated and diluted hydrocarbon stream from the wellbore.
[0259] US31. The viscous hydrocarbon production assembly of paragraph
US29,
wherein the wellbore forms a portion of an injection well, wherein the
assembly further
includes a production well that extends between the surface region and the
subterranean
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formation, wherein the injection well is separate from the production well,
and further
wherein the heated and diluted hydrocarbon production system is configured to
produce the
heated and diluted hydrocarbon stream from the production well.
[0260] US32. A
method of heating and diluting viscous hydrocarbons within a
.. subterranean formation, the method comprising:
continuously supplying a dual-duty agent to the subterranean formation;
periodically supplying an oxidant to the subterranean formation;
combusting a combusted portion of the dual-duty agent with the oxidant in a
heated
zone of the subterranean formation during the periodically supplying;
flowing an uncornbusted portion of the dual-duty agent through the heated zone
to
heat the uncombusted portion of the dual-duty agent and generate a heated dual-
duty agent;
and
contacting the viscous hydrocarbons with the heated dual-duty agent to
generate
heated and diluted hydrocarbons.
[0261] US33. The method of paragraph US32, wherein the periodically
supplying the
oxidant includes ceasing the supplying of the oxidant while continuing the
supplying of the
dual-duty agent to the subterranean formation.
Industrial Applicability
[0262] The
systems and methods disclosed herein are applicable to the oil and gas
industry.
[0263] It is
believed that the disclosure set forth above encompasses multiple distinct
inventions with independent utility. While each of these inventions has been
disclosed in its
preferred form, the specific embodiments thereof as disclosed and illustrated
herein are not to
be considered in a limiting sense as numerous variations are possible. The
subject matter of
the inventions includes all novel and non-obvious combinations and
subcombinations of the
various elements, features, functions and/or properties disclosed herein.
Similarly, where the
claims recite "a" or "a first" element or the equivalent thereof, such claims
should be
understood to include incorporation of one or more such elements, neither
requiring nor
excluding two or more such elements.
[0264] It is believed that the following claims particularly point out
certain combinations
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and subcombinations that are directed to one of the disclosed inventions and
are novel and
non-obvious. Inventions embodied in other combinations and subcombinations of
features,
functions, elements and/or properties may be claimed through amendment of the
present
claims or presentation of new claims in this or a related application. Such
amended or new
claims, whether they are directed to a different invention or directed to the
same invention,
whether different, broader, narrower, or equal in scope to the original
claims, are also
regarded as included within the subject matter of the inventions of the
present disclosure.
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