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 practiced 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 4,026,583 discloses an oil well pipe incorporating a
corrosion-resistant, metallic liner which is intimately metallurgically bonded
to the pipe
bore. A non-metallic annular seal may be provided in an annular groove to seal
off
between the tapered interfitting surfaces between the liner box and pin
sections; for
example, the seal may consist of polytetrafluoroethylene material, as for
example
TEFLON or VITON, and may comprise an O-ring having a radial thickness of
between
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0.025 and 0.225 inches. U.S. Patent Number 4,026,583 is herein incorporated by
reference in its entirety.
U.S. Patent Application Publication Number 2006/0048941 discloses an
apparatus and method for controlling and/or minimizing the formation or
accumulation
of unwanted deposits on the inside of fluid flow paths by employing at various
locations along the path an assembly of permanent magnets oriented such that
the
fluid flow is preferably from the North magnetic pole to the South magnetic
pole.
Suitable materials for use as seals include but are not limited to
fluorocarbon rubber
(FKM)-type seals and O-rings, including KEL-F and FLUOREL (both available from
3M, St. Paul, Minn.), VITON and KALREZ (both available from E.I. DuPont de
Nemours Co.); chlorosulfonated polyethylenes, such as HYPHALON (available from
DuPont Dow Elastomers); PTFE (TEFLON) and filled PTFE such as FLUOROSINT
(available from Quadrant DSM Engineering Plastic Products, Reading, Pa.);
copolymers of butadiene and acrylonitrile, known as Buna-N (nitrile; NBR),
such as
HYVCAR (available from Goodrich Chemical Co.); and silicone or silicone
rubber.
Typically, seals are fluorocarbon rubber-type seals, such as VITON. U.S.
Patent
Application Publication Number 2006/0048941 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
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systems and methods for solvent miscible flooding. There is a further need in
the art
for improved systems and methods for transporting a miscible solvent in a pipe
during
an enhanced oil recovery operation. There is a need in the art for improved
seals to
be used with a miscible solvent in a pipe during an enhanced oil recovery
operation.
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 above the formation; a
second
well above the formation; the first well comprises a mechanism to inject a
miscible
enhanced oil recovery formulation into the formation; the first well comprises
a seal
comprising a fluorinated polymer, the seal adapted to contain the miscible
enhanced
oil recovery formulation within a tubular; and the second well comprises a
mechanism
to produce oil and/or gas from the formation.
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 installing
a seal
in the first well, the seal comprising a fluorinated polymer.
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 systems and methods 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 may be miscible with oil in place.
Improved systems and methods for transporting and/or containing a compound
in a pipe which may be miscible with oil in place.
Improved systems and methods for sealing a compound in a pipe which may
be miscible with oil in place.
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Brief Description of the Drawings
Figure 1 illustrates an oil and/or gas production system.
Figure 2 illustrates an oil and/or gas production system.
Figures 3a-3c illustrate oil and/or gas production systems.
Figure 4 illustrates an oil and/or gas production system.
Figures 5a and 5b illustrate an oil and/or gas production system with a
concentric tubular arrangement.
Figure 6 illustrates a threaded tubular connection.
Detailed Description of the Invention
Figure 2:
Referring now to Figure 2, in some embodiments system 200 is illustrated.
System 200 includes underground formation 202, underground formation 204,
underground formation 206, and underground formation 208. Facility 210 may be
provided at the surface. Well 212 traverses formations 202 and 204, and has
multiple
openings in formation 206. Portions 214 of formation 206 may be optionally
fractured
and/or perforated. During primary production, oil and gas from formation 206
may be
produced into portions 214, into well 212, and travels up to facility 210.
Facility 210
then separates gas, which may be sent to gas processing 216, and liquid, which
may
be sent to liquid storage 218. Facility 210 also includes miscible enhanced
oil
recovery formulation storage 230.
As shown in Figure 2, miscible enhanced oil recovery formulation may be
pumped down well 212 that is shown by the down arrow and pumped into formation
206. Miscible enhanced oil recovery formulation and oil and/or gas may be then
produced back up well 212 to facility 210, as shown by up arrow. Facility 210
may be
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 212.
In some embodiments, miscible enhanced oil recovery formulation may be
pumped into formation 206 below the fracture pressure of the formation, for
example
from about 40% to about 90% of the fracture pressure.
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The recovery of oil and/or gas with one or more wells (such as well 212) from
underground formation 206 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 underground formation 206 is not critical.
Figures 3a and 3b:
Referring now to Figures 3a and 3b, in some embodiments of the invention,
system 200 is illustrated. System 200 includes underground formation 202,
underground formation 204, underground formation 206, and underground
formation
208. Facility 210 may be provided at the surface. Well 212 traverses
formations 202
and 204, and has openings in formation 206. Portions 214 of formation 206 may
be
optionally fractured and/or perforated. During primary production, oil and gas
from
formation 206 may be produced into portions 214, into well 212, and travels up
to
facility 210. Facility 210 then separates gas, which may be sent to gas
processing
216, and liquid, which may be sent to liquid storage 218. Facility 210 also
includes
miscible enhanced oil recovery formulation storage 230.
As shown in Figure 3a, miscible enhanced oil recovery formulation may be
pumped down well 212 that is shown by the down arrow and pumped into formation
206. 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.
After the soaking period, as shown in Figure 3b, miscible enhanced oil
recovery formulation and oil and/or gas may be then produced back up well 212
to
facility 210. Facility 210 may be 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
212, 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 206 below the fracture pressure of the formation, for
example
from about 40% to about 90% of the fracture pressure.
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Figure 3c:
Referring now to Figure 3c, in some embodiments of the invention, system 300
is illustrated. System 300 includes underground formation 302, formation 304,
formation 306, and formation 308. Production facility 310 may be provided at
the
surface. Well 312 traverses formation 302 and 304 has openings at formation
306.
Portions of formation 314 may be optionally fractured and/or perforated. As
oil and
gas is produced from formation 306 it enters portions 314, and travels up well
312 to
production facility 310. Gas and liquid may be separated, and gas may be sent
to gas
storage 316, and liquid may be sent to liquid storage 318. Production facility
310
may be able to produce and/or store miscible enhanced oil recovery
formulation,
which may be produced and stored in production / storage 330. Hydrogen sulfide
and/or other sulfur containing compounds from well 312 may be sent to miscible
enhanced oil recovery formulation production / storage 330. Miscible enhanced
oil
recovery formulation may be pumped down well 332, to portions 334 of formation
306. Miscible enhanced oil recovery formulation traverses formation 306 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 312, to production facility 310.
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 332.
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 332, followed by another component to force miscible
enhanced oil
recovery formulation or miscible enhanced oil recovery formulation mixed with
other
components across formation 306, 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.
Figure 4:
Referring now to Figure 4, in some embodiments of the invention, system 700
is illustrated. System 700 includes underground formation 702, formation 704,
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formation 706, and formation 708; and underground formation 802, formation
804,
formation 806, and formation 808. Production facility 710 is provided at the
surface.
Well 712 traverses formation 702 and 704 has openings at formation 706.
Portions of
formation 714 may be optionally fractured and/or perforated. As oil and gas is
produced from formation 706 it enters portions 714, and travels up well 712 to
production facility 710. Gas and liquid may be separated, and gas may be sent
to gas
storage 716, and liquid may be sent to liquid storage 718. Production facility
710 is
able to produce carbon disulfide and/or carbon oxysulfide formulation, which
may be
produced and stored in carbon disulfide formulation production 730. Hydrogen
sulfide
and/or other sulfur containing compounds from well 712 may be sent to carbon
disulfide formulation production 730. Carbon disulfide formulation is
transported to
well 732 by pipe 734 and pumped down well 732, to formation 806. Carbon
disulfide
formulation may be used in formation 806 to aid in the production of oil and
gas from
formation 806.
Well 732 is separated from well 712 by a distance d 740. In some
embodiments, distanced 740 is from about 1 to about 1000 kilometers, for
example
from about 5 to about 250 kilometers, or for example from about 10 to about
100
kilometers, or for example about 50 to 75 kilometers.
Figures 5a & 5b:
Referring now to Figure 5a, a tubular 900 is illustrated traversing formations
802 and 804, and ending in formation 806. Tubular 900 may be used as an
observation well, a peripheral containment well, an injection well, and/or a
production
well.
Referring now to Figure 5b, tubular 900 is shown in more detail. Tubular 900
includes internal tubular 902 located within external tubular 904. Internal
tubular 902
is made up of multiple sections, connected at joints 908. External tubular 904
is
made up of multiple sections, connected at joints 910. Packer 906 may be
provided
between the exterior of tubular 902 and the interior of tubular 904. Packer
may seal
off an upper annular space between the exterior of tubular 902 and the
interior of
tubular 904 from a lower annular space, for example a production or injection
zone.
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Packer 906 may have one or more sealing elements on its interior surface
adjacent tubular 902 and/or one or more sealing elements on its exterior
surface
adjacent tubular 904.
Figure 6:
Referring now to Figure 6, tubular system 1000 with threaded tubular
connection 1008 is illustrated. Tubular 1030 having pin end 1012 is
threadingly
engaged with tubular 1020 having box end 1010. Pin end 1012 is the male
connection which fits within box end 1010 which is the female connection.
One or more seals 1014 and/or 1016 may be provided adjacent the threaded
connections. Seals 1014 and/or 1016 may be o-rings or other seal
configurations as
are known in the art. Seals 1014 and/or 1016 may be fitted into grooves on
tubulars
1020 and/or 1030. Seals 1014 and/or 1016 may be used to provide a seal between
an interior and exterior of tubulars 1020 and 1030, for example to contain
fluids within
tubulars 1020 and 1030 and/or to keep fluids out of tubulars 1020 and 1030.
Tubular system 1000 may be representative of one or more parts of well 212,
312, 332, 712, 732, and/or tubular 900, 902, and/or 904.
Seal Materials:
In some embodiments, seals 1014 and/or 1016 and packer 906 may be made
of fluorinated polymers such as PTFE (polytetrafluoroethylene), fluorinated
ethylene-
propylene copolymers, commercially available as Teflon TM from Du Pont;
fluoroelastomers such as a copolymer of vinylidene fluoride and
hexafluoropropylene,
commercially available as VitonTM from Du Pont, for example Viton A; or
perfluoroelastomers such as a copolymer of vinylidene fluoride and
hexafluoropropylene, commercially available as KalrezTM from Du Pont, for
example
Kalrez AS-568 3018-1.
In some embodiments, seals 1014 and/or 1016 and packer 906 may be made
of fluorocarbon polymers, perfluorocarbon polymers, fluoroelastomers, or
perfluoroelastomers.
In some embodiments, seals 1014 and/or 1016 and packer 906 may be made
of a fluorinated polymer, where at least about 25% of the hydrogens attached
to a
carbon have been replaced with a fluorine or chlorine, for example replacing
at least
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about 50% of the hydrogens, at least about 75% of the hydrogens, or at least
about
90% of the hydrogens.
Alternative Embodiments:
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, a carbon oxysulfide formulation, and/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 or a carbon oxysulfide
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.
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Patent Application having serial number 11/409,436 is herein incorporated by
reference in its entirety.
In some embodiments, suitable miscible enhanced oil recovery agents include
carbon disulfide, carbon oxysulfide, 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, 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.
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
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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.
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.
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
produced
to produce commercial products such as transportation fuels such as gasoline
and
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diesel, 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 above the
formation; a second well above the formation; the first well comprises a
mechanism to
inject a miscible enhanced oil recovery formulation into the formation; the
first well
comprises a seal comprising a fluorinated polymer, the seal adapted to contain
the
miscible enhanced oil recovery formulation within a tubular; and the second
well
comprises a mechanism to produce oil and/or gas from the formation. 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, a carbon
oxysulfide 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 miscible enhanced oil recovery formulation comprises a carbon
disulfide formulation, a carbon oxysulfide formulation, or 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 miscible
enhanced oil recovery formulation comprising a carbon disulfide formulation.
In some
embodiments, the system also includes a mechanism for producing a carbon
disulfide
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formulation. In some embodiments, the underground formation comprises an oil
having a viscosity from 100 to 5,000,000 centipoise.
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
installing a seal in the first well, the seal comprising a fluorinated
polymer. 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 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 some embodiments, the fluorinated polymer is at least 40%
fluorinated. In some embodiments, the fluorinated polymer is at least 80%
fluorinated. In some embodiments, the fluorinated polymer is selected from the
group
consisting of polytetrafluoroethylene, fluorinated ethylene-propylene
copolymers,
fluoroelastomers, copolymers of vinylidene fluoride and hexafluoropropylene,
or
perfluoroelastomers.
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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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