Note: Descriptions are shown in the official language in which they were submitted.
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SYSTEMS AND METHODS FOR PRODUCING OIL AND/OR GAS
Field of the Invention
The present disclosure relates to systems and methods for producing oil and/or
gas.
Background of the Invention
Enhanced Oil Recovery (EOR) may be used to increase oil recovery in fields
worldwide. There are three main types of EOR, thermal, chemical/polymer and
gas
injection, which may be used to increase oil recovery from a reservoir, beyond
what
can be achieved by conventional means - possibly extending the life of a field
and
boosting the oil recovery factor.
Thermal enhanced recovery works by adding heat to the reservoir. The most
widely practised form is a steamdrive, which reduces oil viscosity so that it
can flow to
the producing wells. Chemical flooding increases recovery by reducing the
capillary
forces that trap residual oil. Polymer flooding improves the sweep efficiency
of
injected water. Miscible injection works in a similar way to chemical
flooding. By
injecting a fluid that is miscible with the oil, trapped residual oil can be
recovered.
Referring to Figure 1, there is illustrated prior art system 100. System 100
includes underground formation 102, underground formation 104, underground
formation 106, and underground formation 108. Production facility 110 is
provided at
the surface. Well 112 traverses formations 102 and 104, and terminates in
formation
106. The portion of formation 106 is shown at 114. Oil and gas are produced
from
formation 106 through well 112, to production facility 110. Gas and liquid are
separated from each other, gas is stored in gas storage 116 and liquid is
stored in
liquid storage 118.
U.S. Patent Number 7,225,866 discloses that an oil shale formation may be
treated using an in situ thermal process. A mixture of hydrocarbons, H2,
and/or other
formation fluids may be produced from the formation. Heat may be applied to
the
formation to raise a temperature of a portion of the formation to a pyrolysis
temperature. Heat sources may be used to heat the formation. The heat sources
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may be positioned within the formation in a selected pattern. U.S. Patent
Number
7,225,866 is herein incorporated by reference in its entirety.
Co-pending U.S. Patent Application Publication Number 2006/0254769,
published November 16, 2006, and having attorney docket number TH2616,
discloses a system including a mechanism for recovering oil and/or gas from an
underground formation, the oil and/or gas comprising one or more sulfur
compounds;
a mechanism for converting at least a portion of the sulfur compounds from the
recovered oil and/or gas into a carbon disulfide formulation; and a mechanism
for
releasing at least a portion of the carbon disulfide formulation into a
formation. U.S.
Patent Application Publication Number 2006/0254769 is herein incorporated by
reference in its entirety.
There is a need in the art for improved systems and methods for enhanced oil
recovery. There is a further need in the art for improved systems and methods
for
enhanced oil recovery using a solvent, for example through viscosity
reduction,
chemical effects, and miscible flooding. There is a further need in the art
for improved
systems and methods for solvent miscible flooding.
Summary of the Invention
In one aspect, the invention provides a system for producing oil and/or gas
from an underground formation comprising a first well in the formation; a
mechanism
to inject a miscible enhanced oil recovery formulation into the first well; a
second well
in the formation; a mechanism to produce oil and/or gas from the second well;
wherein the first well and the second well comprise an interior of the system;
a
plurality of containment wells exterior to the first well and the second well;
and a
mechanism to inject a containment agent into the containment wells.
In another aspect, the invention provides a method for producing oil and/or
gas
comprising injecting a carbon disulfide formulation into a formation from a
first well;
producing oil and/or gas from the formation from a second well; and injecting
a
containment agent into the formation from a plurality of containment wells. In
some
embodiments, the method also includes recovering carbon disulfide formulation
from
the oil and/or gas, if present, and then injecting at least a portion of the
recovered
carbon disulfide formulation into the formation.
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In another aspect, the invention provides a method for producing oil and/or
gas
comprising injecting a miscible enhanced oil recovery formulation into a
formation
from a first well; producing oil and/or gas from the formation from a second
well; and
injecting a containment agent into the formation from plurality of containment
wells.
Advantages of the invention include one or more of the following:
Improved systems and methods for enhanced recovery of hydrocarbons from a
formation with a solvent.
Improved systems and methods for enhanced recovery of hydrocarbons from a
formation with a fluid containing a miscible solvent.
Improved compositions and/or techniques for secondary recovery of
hydrocarbons.
Improved systems and methods for enhanced oil recovery.
Improved systems and methods for enhanced oil recovery using a miscible
solvent.
Improved systems and methods for enhanced oil recovery using a compound
which is miscible with oil in place.
Brief Description of the Drawings
Figure 1 illustrates an oil and/or gas production system.
Figure 2a illustrates a well pattern.
Figures 2b and 2c illustrate the well pattern of Figure 2a during enhanced oil
recovery processes.
Figures 3a-3c illustrate oil and/or gas production systems.
Figure 4 illustrates a well pattern.
Detailed Description of the Invention
Figure 2a:
Referring now to Figure 2a, in some embodiments, an array of wells 200 is
illustrated. Array 200 includes well group 202 (denoted by horizontal lines)
and well
group 204 (denoted by diagonal lines).
Array 200 defines a production area, enclosed by the rectangle. Array 200
defines an interior of the system. Exterior to array 200 are located a
plurality of
containment wells 250.
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Each well in well group 202 has horizontal distance 230 from the adjacent well
in well group 202. Each well in well group 202 has vertical distance 232 from
the
adjacent well in well group 202.
Each well in well group 204 has horizontal distance 236 from the adjacent well
in well group 204. Each well in well group 204 has vertical distance 238 from
the
adjacent well in well group 204.
As shown in Figure 2a, horizontal distance 230 and horizontal distance 236
refer to a distance from left to right of the paper, and vertical distance 232
and vertical
distance 238 refer to a distance from up to down of the paper. In practice,
array may
be composed of vertical wells that are perpendicular to the earth's surface,
horizontal
wells that are parallel to the earth's surface, or wells that are inclined at
some other
angle, for example 30 to 60 degrees with respect to the earth's surface.
Each well in well group 202 is distance 234 from the adjacent wells in well
group 204. Each well in well group 204 is distance 234 from the adjacent wells
in well
group 202.
In some embodiments, each well in well group 202 is surrounded by four wells
in well group 204. In some embodiments, each well in well group 204 is
surrounded
by four wells in well group 202.
In some embodiments, horizontal distance 230 is from about 5 to about 1000
meters, or from about 10 to about 500 meters, or from about 20 to about 250
meters,
or from about 30 to about 200 meters, or from about 50 to about 150 meters, or
from
about 90 to about 120 meters, or about 100 meters.
In some embodiments, vertical distance 232 is from about 5 to about 1000
meters, or from about 10 to about 500 meters, or from about 20 to about 250
meters,
or from about 30 to about 200 meters, or from about 50 to about 150 meters, or
from
about 90 to about 120 meters, or about 100 meters.
In some embodiments, horizontal distance 236 is from about 5 to about 1000
meters, or from about 10 to about 500 meters, or from about 20 to about 250
meters,
or from about 30 to about 200 meters, or from about 50 to about 150 meters, or
from
about 90 to about 120 meters, or about 100 meters.
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In some embodiments, vertical distance 238 is from about 5 to about 1000
meters, or from about 10 to about 500 meters, or from about 20 to about 250
meters,
or from about 30 to about 200 meters, or from about 50 to about 150 meters, or
from
about 90 to about 120 meters, or about 100 meters.
In some embodiments, distance 234 is from about 5 to about 1000 meters, or
from about 10 to about 500 meters, or from about 20 to about 250 meters, or
from
about 30 to about 200 meters, or from about 50 to about 150 meters, or from
about 90
to about 120 meters, or about 100 meters.
In some embodiments, array of wells 200 may have from about 10 to about
1000 wells, for example from about 5 to about 500 wells in well group 202, and
from
about 5 to about 500 wells in well group 204. There may be provided from about
2 to
about 1000 containment wells 250, for example from about 5 to about 500, or
from
about 10 to about 200.
In some embodiments, array of wells 200 is seen as a top view with well group
202 and well group 204 being vertical wells spaced on a piece of land. In some
embodiments, array of wells 200 is seen as a cross-sectional side view with
well
group 202 and well group 204 being horizontal wells spaced within a formation.
The recovery of oil and/or gas with array of wells 200 from an underground
formation may be accomplished by any known method. Suitable methods include
subsea production, surface production, primary, secondary, or tertiary
production.
The selection of the method used to recover the oil and/or gas from the
underground
formation is not critical.
The containment of oil and/or gas and/or an enhanced oil recovery agent with
containment wells 250 may be accomplished by any known method. Suitable
methods include pumping water, a peroxide such as hydrogen peroxide or a
solution
of hydrogen peroxide in water, carbon dioxide, natural gas or other gaseous or
liquid
hydrocarbons, nitrogen, air, brine, or other liquids or gases into containment
wells
250. In another embodiment, containment wells 250 may be used to create a
freeze
wall barrier. One suitable freeze wall barrier is disclosed in U.S. Patent
Number
7,225,866 is herein incorporated by reference in its entirety. The selection
of the
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method used to contain oil and/or gas and/or an enhanced oil recovery agent
with
containment wells 250 is not critical.
In some embodiments, oil and/or gas may be recovered from a formation into a
well, and flow through the well and flowline to a facility. In some
embodiments,
enhanced oil recovery, with the use of an agent for example steam, water, a
surfactant, a polymer flood, and/or a miscible agent such as a carbon
disulfide
formulation or carbon dioxide, may be used to increase the flow of oil and/or
gas from
the formation.
In some embodiments, oil and/or gas recovered from a formation may include
a sulfur compound. The sulfur compound may include hydrogen sulfide,
mercaptans,
sulfides and disulfides other than hydrogen disulfide, or heterocyclic sulfur
compounds for example thiophenes, benzothiophenes, or substituted and
condensed
ring dibenzothiophenes, or mixtures thereof.
In some embodiments, a sulfur compound from the formation may be
converted into a carbon disulfide formulation. The conversion of at least a
portion of
the sulfur compound into a carbon disulfide formulation may be accomplished by
any
known method. Suitable methods may include oxidation reaction of the sulfur
compound to sulfur and/or sulfur dioxides, and by reaction of sulfur and/or
sulfur
dioxide with carbon and/or a carbon containing compound to form the carbon
disulfide
formulation. The selection of the method used to convert at least a portion of
the
sulfur compound into a carbon disulfide formulation is not critical.
In some embodiments, a suitable miscible enhanced oil recovery agent may be
a carbon disulfide formulation. The carbon disulfide formulation may include
carbon
disulfide and/or carbon disulfide derivatives for example, thiocarbonates,
xanthates
and mixtures thereof; and optionally one or more of the following: hydrogen
sulfide,
sulfur, carbon dioxide, hydrocarbons, and mixtures thereof.
In some embodiments, a suitable method of producing a carbon disulfide
formulation is disclosed in copending U.S. Patent Application having serial
number
11/409,436, filed on April 19, 2006, having attorney docket number TH2616.
U.S.
Patent Application having serial number 11/409,436 is herein incorporated by
reference in its entirety.
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Figure 2b:
Referring now to Figure 2b, in some embodiments, array of wells 200 is
illustrated. Array 200 includes well group 202 (denoted by horizontal lines)
and well
group 204 (denoted by diagonal lines). Containment wells 250 are provided
about
array of wells 200.
In some embodiments, a miscible enhanced oil recovery agent is injected into
well group 204, and oil is recovered from well group 202. As illustrated, the
miscible
enhanced oil recovery agent has injection profile 208, and oil recovery
profile 206 is
being produced to well group 202. In some embodiments, a containment agent is
injected into containment wells 250. As illustrated, the containment agent has
an
injection profile about each of the containment wells 250. Containment agent
may be
used to force miscible enhanced oil recovery agent and/or oil and/or gas
towards
producing well group 202.
In some embodiments, a miscible enhanced oil recovery agent is injected into
well group 202, and oil is recovered from well group 204. As illustrated, the
miscible
enhanced oil recovery agent has injection profile 206, and oil recovery
profile 208 is
being produced to well group 204. In some embodiments, a containment agent is
injected into containment wells 250. As illustrated, the containment agent has
an
injection profile about each of the containment wells 250. Containment agent
may be
used to force miscible enhanced oil recovery agent and/or oil and/or gas
towards
producing well group 204.
In some embodiments, well group 202 may be used for injecting a miscible
enhanced oil recovery agent, and well group 204 may be used for producing oil
and/or gas from the formation for a first time period; then well group 204 may
be used
for injecting a miscible enhanced oil recovery agent, and well group 202 may
be used
for producing oil and/or gas from the formation for a second time period,
where the
first and second time periods comprise a cycle.
In some embodiments, multiple cycles may be conducted which include
alternating well groups 202 and 204 between injecting a miscible enhanced oil
recovery agent, and producing oil and/or gas from the formation, where one
well
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group is injecting and the other is producing for a first time period, and
then they are
switched for a second time period.
In some embodiments, a cycle may be from about 12 hours to about 1 year, or
from about 3 days to about 6 months, or from about 5 days to about 3 months.
In
some embodiments, each cycle may increase in time, for example each cycle may
be
from about 5% to about 10% longer than the previous cycle, for example about
8%
longer.
In some embodiments, a miscible enhanced oil recovery agent or a mixture
including a miscible enhanced oil recovery agent may be injected at the
beginning of
a cycle, and an immiscible enhanced oil recovery agent or a mixture including
an
immiscible enhanced oil recovery agent may be injected at the end of the
cycle. In
some embodiments, the beginning of a cycle may be the first 10% to about 80%
of a
cycle, or the first 20% to about 60% of a cycle, the first 25% to about 40% of
a cycle,
and the end may be the remainder of the cycle.
In some embodiments, suitable miscible enhanced oil recovery agents include
carbon disulfide, hydrogen sulfide, carbon dioxide, octane, pentane, LPG, C2-
C6
aliphatic hydrocarbons, nitrogen, diesel, mineral spirits, naptha solvent,
asphalt
solvent, kerosene, acetone, xylene, trichloroethane, or mixtures of two or
more of the
preceding, or other miscible enhanced oil recovery agents as are known in the
art. In
some embodiments, suitable miscible enhanced oil recovery agents are first
contact
miscible or multiple contact miscible with oil in the formation.
In some embodiments, suitable immiscible enhanced oil recovery agents
include water in gas or liquid form, air, mixtures of two or more of the
preceding, or
other immiscible enhanced oil recovery agents as are known in the art. In some
embodiments, suitable immiscible enhanced oil recovery agents are not first
contact
miscible or multiple contact miscible with oil in the formation.
In some embodiments, an immiscible enhanced oil recovery agent and/or a
miscible enhanced oil recovery agent may be used as a containment agent and
injected into containment wells 250.
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In some embodiments, immiscible and/or miscible enhanced oil recovery
agents injected into the formation may be recovered from the produced oil
and/or gas
and re-injected into the formation.
In some embodiments, oil as present in the formation prior to the injection of
any enhanced oil recovery agents has a viscosity of at least about 100
centipoise, or
at least about 500 centipoise, or at least about 1000 centipoise, or at least
about 2000
centipoise, or at least about 5000 centipoise, or at least about 10,000
centipoise. In
some embodiments, oil as present in the formation prior to the injection of
any
enhanced oil recovery agents has a viscosity of up to about 5,000,000
centipoise, or
up to about 2,000,000 centipoise, or up to about 1,000,000 centipoise, or up
to about
500,000 centipoise.
Figure 2c:
Referring now to Figure 2c, in some embodiments, array of wells 200 is
illustrated. Array 200 includes well group 202 (denoted by horizontal lines)
and well
group 204 (denoted by diagonal lines). Containment wells 250 are located
exterior to
array 200 to form a perimeter about array 200.
In some embodiments, a miscible enhanced oil recovery agent is injected into
well group 204, and oil is recovered from well group 202. As illustrated, the
miscible
enhanced oil recovery agent has injection profile 208 with overlap 210 with
oil
recovery profile 206, which is being produced to well group 202. In some
embodiments, a containment agent is injected into containment wells 250. As
illustrated, the containment agent has an injection profile about each of the
containment wells 250. Containment agent may be used to force miscible
enhanced
oil recovery agent and/or oil and/or gas towards producing well group 202.
After a
sufficient period of time containment agent injection profile may overlap with
one or
more of injection profile 208 and oil recovery profile 206 so that enhanced
oil recovery
agent is contained within array 200; and/or so that oil and/or gas is
contained within
array 200; and/or so that containment agent is produced to well group 202.
In some embodiments, a miscible enhanced oil recovery agent is injected into
well group 202, and oil is recovered from well group 204. As illustrated, the
miscible
enhanced oil recovery agent has injection profile 206 with overlap 210 with
oil
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recovery profile 208, which is being produced to well group 204. In some
embodiments, a containment agent is injected into containment wells 250. As
illustrated, the containment agent has an injection profile about each of the
containment wells 250. Containment agent may be used to force miscible
enhanced
oil recovery agent and/or oil and/or gas towards producing well group 204.
After a
sufficient period of time containment agent injection profile may overlap with
one or
more of injection profile 208 and oil recovery profile 206 so that enhanced
oil recovery
agent is contained within array 200; and/or so that oil and/or gas is
contained within
array 200; and/or so that containment agent is produced to well group 204.
Releasing at least a portion of the miscible enhanced oil recovery agent
and/or
other liquids and/or gases may be accomplished by any known method. One
suitable
method is injecting the miscible enhanced oil recovery formulation into a
single
conduit in a single well, allowing carbon disulfide formulation to soak, and
then
pumping out at least a portion of the carbon disulfide formulation with gas
and/or
liquids. Another suitable method is injecting the miscible enhanced oil
recovery
formulation into a first well, and pumping out at least a portion of the
miscible
enhanced oil recovery formulation with gas and/or liquids through a second
well. The
selection of the method used to inject at least a portion of the miscible
enhanced oil
recovery formulation and/or other liquids and/or gases is not critical.
In some embodiments, the miscible enhanced oil recovery formulation and/or
other liquids and/or gases may be pumped into a formation at a pressure up to
the
fracture pressure of the formation.
In some embodiments, the miscible enhanced oil recovery formulation may be
mixed in with oil and/or gas in a formation to form a mixture which may be
recovered
from a well. In some embodiments, a quantity of the miscible enhanced oil
recovery
formulation may be injected into a well, followed by another component to
force
carbon the formulation across the formation. For example air, water in liquid
or vapor
form, carbon dioxide, other gases, other liquids, and/or mixtures thereof may
be used
to force the miscible enhanced oil recovery formulation across the formation.
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In some embodiments, the miscible enhanced oil recovery formulation may be
heated prior to being injected into the formation to lower the viscosity of
fluids in the
formation, for example heavy oils, paraffins, asphaltenes, etc.
In some embodiments, the miscible enhanced oil recovery formulation may be
heated and/or boiled while within the formation, with the use of a heated
fluid or a
heater, to lower the viscosity of fluids in the formation. In some
embodiments, heated
water and/or steam may be used to heat and/or vaporize the miscible enhanced
oil
recovery formulation in the formation.
In some embodiments, the miscible enhanced oil recovery formulation may be
heated and/or boiled while within the formation, with the use of a heater. One
suitable
heater is disclosed in copending United States Patent Application having
serial
number 10/693,816, filed on October 24, 2003, and having attorney docket
number
TH2557. United States Patent Application having serial number 10/693,816 is
herein
incorporated by reference in its entirety.
Figures 3a & 3b:
Referring now to Figures 3a and 3b, in some embodiments of the invention,
system 300 is illustrated. System 300 includes underground formation 302,
underground formation 304, underground formation 306, and underground
formation
308. Facility 310 is provided at the surface. Well 312 traverses formations
302 and
304, and has openings in formation 306. Portions 314 of formation 306 may be
optionally fractured and/or perforated. During primary production, oil and gas
from
formation 306 is produced into portions 314, into well 312, and travels up to
facility
310. Facility 310 then separates gas, which is sent to gas processing 316, and
liquid,
which is sent to liquid storage 318. Facility 310 also includes miscible
enhanced oil
recovery formulation storage 330. As shown in Figure 3a, miscible enhanced oil
recovery formulation may be pumped down well 312 that is shown by the down
arrow
and pumped into formation 306. Miscible enhanced oil recovery formulation may
be
left to soak in formation for a period of time from about 1 hour to about 15
days, for
example from about 5 to about 50 hours.
Containment well 350 with injection mechanism 352 and containment well 360
with injection mechanism 362 may be provided to contain miscible enhanced oil
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recovery formulation between containment well 350 and containment well 360.
Injection mechanisms 352 and 362 may be used to inject a containment agent,
for
example a refrigerant to create a freeze wall, cement, liquid sulfur, or a
liquid or gas
such as water, peroxide, a peroxide solution, carbon dioxide, natural gas,
other C, -
C15 hydrocarbons, nitrogen, or air.
After the soaking period, as shown in Figure 3b, miscible enhanced oil
recovery formulation and oil and/or gas is then produced back up well 312 to
facility
310. Facility 310 is adapted to separate and/or recycle miscible enhanced oil
recovery formulation, for example by boiling the formulation, condensing it or
filtering
or reacting it, then re-injecting the formulation into well 312, for example
by repeating
the soaking cycle shown in Figures 3a and 3b from about 2 to about 5 times.
In some embodiments, miscible enhanced oil recovery formulation may be
pumped into formation 306 below the fracture pressure of the formation, for
example
from about 40% to about 90% of the fracture pressure.
In some embodiments, well 312 as shown in Figure 3a injecting into formation
306 may be representative of a well in well group 202, and well 312 as shown
in
Figure 3b producing from formation 306 may be representative of a well in well
group
204.
In some embodiments, well 312 as shown in Figure 3a injecting into formation
306 may be representative of a well in well group 204, and well 312 as shown
in
Figure 3b producing from formation 306 may be representative of a well in well
group
202.
Figure 3c:
Referring now to Figure 3c, in some embodiments of the invention, system 400
is illustrated. System 400 includes underground formation 402, formation 404,
formation 406, and formation 408. Production facility 410 is provided at the
surface.
Well 412 traverses formation 402 and 404 has openings at formation 406.
Portions of
formation 414 may be optionally fractured and/or perforated. As oil and gas is
produced from formation 406 it enters portions 414, and travels up well 412 to
production facility 410. Gas and liquid may be separated, and gas may be sent
to gas
storage 416, and liquid may be sent to liquid storage 418. Production facility
410 is
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able to produce and/or store miscible enhanced oil recovery formulation, which
may
be produced and stored in production / storage 430. Hydrogen sulfide and/or
other
sulfur containing compounds from well 412 may be sent to miscible enhanced oil
recovery formulation production / storage 430. Miscible enhanced oil recovery
formulation is pumped down well 432, to portions 434 of formation 406.
Miscible
enhanced oil recovery formulation traverses formation 406 to aid in the
production of
oil and gas, and then the miscible enhanced oil recovery formulation, oil
and/or gas
may all be produced to well 412, to production facility 410. Miscible enhanced
oil
recovery formulation may then be recycled, for example by boiling the
formulation,
condensing it or filtering or reacting it, then re-injecting the formulation
into well 432.
Containment well 450 with injection mechanism 452 and containment well 460
with injection mechanism 462 may be provided to contain miscible enhanced oil
recovery formulation between containment well 450 and containment well 460.
Injection mechanisms 452 and 462 may be used to inject a containment agent,
for
example a refrigerant to create a freeze wall, or a liquid or gas such as
water,
peroxide, a peroxide solution, carbon dioxide, natural gas, other C1 - C15
hydrocarbons, nitrogen, or air, or mixtures thereof.
In some embodiments, a quantity of miscible enhanced oil recovery formulation
or miscible enhanced oil recovery formulation mixed with other components may
be
injected into well 432, followed by another component to force miscible
enhanced oil
recovery formulation or miscible enhanced oil recovery formulation mixed with
other
components across formation 406, for example air; water in gas or liquid form;
water
mixed with one or more salts, polymers, and/or surfactants; carbon dioxide;
other
gases; other liquids; and/or mixtures thereof.
In some embodiments, well 412 which is producing oil and/or gas is
representative of a well in well group 202, and well 432 which is being used
to inject
miscible enhanced oil recovery formulation is representative of a well in well
group
204.
In some embodiments, well 412 which is producing oil and/or gas is
representative of a well in well group 204, and well 432 which is being used
to inject
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miscible enhanced oil recovery formulation is representative of a well in well
group
202.
Figure 4:
Referring now to Figure 4, in some embodiments of the invention, an array of
wells 500 is illustrated. Array 500 includes well group 502 (denoted by
horizontal
lines) and well group 504 (denoted by diagonal lines).
Array 500 defines a production area, enclosed by the rectangle. Array 500
defines an interior of the system. Exterior to array 500 are located internal
containment wells 550, and external containment wells 552. Other arrays of
containment wells may also be provided (not shown).
In some embodiments, a containment agent may be injected into internal
containment wells 550 and external containment wells 552. In another
embodiment,
a containment agent may be injected into external containment wells 552, and
the
containment agent, oil and/or gas, and/or an enhanced oil recovery agent may
be
produced from internal containment wells 550.
Each well in well group 502 has horizontal distance 530 from the adjacent well
in well group 502. Each well in well group 502 has vertical distance 532 from
the
adjacent well in well group 502.
Each well in well group 504 has horizontal distance 536 from the adjacent well
in well group 504. Each well in well group 504 has vertical distance 538 from
the
adjacent well in well group 504.
Each well in well group 502 is distance 534 from the adjacent wells in well
group 504. Each well in well group 504 is distance 534 from the adjacent wells
in well
group 502.
In some embodiments, each well in well group 502 is surrounded by four wells
in well group 504. In some embodiments, each well in well group 504 is
surrounded
by four wells in well group 502.
Alternatives:
In some embodiments, oil and/or gas produced may be transported to a
refinery and/or a treatment facility. The oil and/or gas may be processed to
produce
commercial products such as transportation fuels such as gasoline and diesel,
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heating fuel, lubricants, chemicals, and/or polymers. Processing may include
distilling
and/or fractionally distilling the oil and/or gas to produce one or more
distillate
fractions. In some embodiments, the oil and/or gas, and/or the one or more
distillate
fractions may be subjected to a process of one or more of the following:
catalytic
cracking, hydrocracking, hydrotreating, coking, thermal cracking, distilling,
reforming,
polymerization, isomerization, alkylation, blending, and dewaxing.
Illustrative Embodiments:
In one embodiment of the invention, there is disclosed a system for producing
oil and/or gas from an underground formation comprising a first well in the
formation;
a mechanism to inject a miscible enhanced oil recovery formulation into the
first well;
a second well in the formation; a mechanism to produce oil and/or gas from the
second well; wherein the first well and the second well comprise an interior
of the
system; a plurality of containment wells exterior to the first well and the
second well;
and a mechanism to inject a containment agent into the containment wells. In
some
embodiments, the first well is at a distance of 10 meters to 1 kilometer from
the
second well. In some embodiments, the underground formation is beneath a body
of
water. In some embodiments, the system also includes a mechanism for injecting
an
immiscible enhanced oil recovery formulation into the formation, after the
miscible
enhanced oil recovery formulation has been released into the formation. In
some
embodiments, the system also includes a miscible enhanced oil recovery
formulation
selected from the group consisting of a carbon disulfide formulation, hydrogen
sulfide,
carbon dioxide, octane, pentane, LPG, C2-C6 aliphatic hydrocarbons, nitrogen,
diesel, mineral spirits, naptha solvent, asphalt solvent, kerosene, acetone,
xylene,
trichloroethane, and mixtures thereof. In some embodiments, the system also
includes an immiscible enhanced oil recovery formulation selected from the
group
consisting of water in gas or liquid form, air, and mixtures thereof. In some
embodiments, the system also includes a first array of wells comprising from 5
to 500
wells, and a second array of wells comprising from 5 to 500 wells. In some
embodiments, the system also includes a miscible enhanced oil recovery
formulation
comprising a carbon disulfide formulation. In some embodiments, the system
also
includes a mechanism for producing a carbon disulfide formulation. In some
CA 02730284 2011-01-07
WO 2010/009118 PCT/US2009/050530
embodiments, the underground formation comprises an oil having a viscosity
from
100 to 5,000,000 centipoise. In some embodiments, the first well comprises a
miscible enhanced oil recovery formulation profile in the formation, and the
second
well comprises an oil recovery profile in the formation, the system further
comprising
an overlap between the miscible enhanced oil recovery formulation profile and
the oil
recovery profile. In some embodiments, the containment agent is selected from
the
group consisting of a refrigerant, water, brine, peroxide, peroxide solutions,
nitrogen,
air, carbon dioxide, natural gas, other C1 - C15 hydrocarbons, and mixtures
thereof.
In some embodiments, the containment agent comprises water. In some
embodiments, the second well produces the containment agent. In some
embodiments, the second well produces the containment agent, the miscible
enhanced oil recovery formulation, and oil and/or gas.
In one embodiment of the invention, there is disclosed a method for producing
oil and/or gas comprising injecting a carbon disulfide formulation into a
formation from
a first well; producing oil and/or gas from the formation from a second well;
and
injecting a containment agent into the formation from a plurality of
containment wells.
In some embodiments, the method also includes recovering carbon disulfide
formulation from the oil and/or gas, if present, and then injecting at least a
portion of
the recovered carbon disulfide formulation into the formation. In some
embodiments,
injecting the carbon disulfide formulation comprises injecting at least a
portion of the
carbon disulfide formulation into the formation in a mixture with one or more
of
hydrocarbons; sulfur compounds other than carbon disulfide; carbon dioxide;
carbon
monoxide; or mixtures thereof. In some embodiments, the method also includes
heating the carbon disulfide formulation prior to injecting the carbon
disulfide
formulation into the formation, or while within the formation. In some
embodiments,
the carbon disulfide formulation is injected at a pressure from 0 to 37,000
kilopascals
above the initial reservoir pressure, measured prior to when carbon disulfide
injection
begins. In some embodiments, the underground formation comprises a
permeability
from 0.0001 to 15 Darcies, for example a permeability from 0.001 to 1 Darcy.
In
some embodiments, any oil, as present in the underground formation prior to
the
injecting the carbon disulfide formulation, has a sulfur content from 0.5% to
5%, for
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example from 1 % to 3%. In some embodiments, the method also includes
converting
at least a portion of the recovered oil and/or gas into a material selected
from the
group consisting of transportation fuels such as gasoline and diesel, heating
fuel,
lubricants, chemicals, and/or polymers.
In one embodiment of the invention, there is disclosed a method for producing
oil and/or gas comprising injecting a miscible enhanced oil recovery
formulation into a
formation from a first well; producing oil and/or gas from the formation from
a second
well; and injecting a containment agent into the formation from plurality of
containment wells. In some embodiments, the method also includes injecting an
immiscible enhanced oil recovery formulation after injecting the miscible
enhanced oil
recovery formulation, to push the miscible enhanced oil recovery formulation
through
the formation. In some embodiments, the miscible enhanced oil recovery
formulation
comprises a carbon disulfide formulation.
Those of skill in the art will appreciate that many modifications and
variations
are possible in terms of the disclosed embodiments of the invention,
configurations,
materials and methods without departing from their spirit and scope.
Accordingly, the
scope of the claims appended hereafter and their functional equivalents should
not be
limited by particular embodiments described and illustrated herein, as these
are
merely exemplary in nature.
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