Abstract: A method of stimulating coalbed methane production by injecting gas into a producer and subsequently placing the producer back on production is described. A decrease in water production may also result. The increase in gas production and decrease in water production may result from: (1) the displacement of water from the producer by gas; (2) the establishment of a mobile gas saturation at an extended distance into the coalbed, extending outward from the producer; and (3) the reduction in coalbed methane partial pressure between the coal matrix and the coal's cleat system.
Type:
Grant
Filed:
June 6, 2001
Date of Patent:
September 17, 2002
Assignee:
The University of Wyoming Research Corporation
Abstract: A method and system for tertiary or enhanced oil recovery from a subterranean liquid hydrocarbon or oil wells is described. The method uses packers (104, 105, 204, 205, 304, 305, 305A, 305B) or angled wells (401) in order to force the gas down into the oil bearing strata (502) from a gas containing strata (501). The result is increased production of oil since the gas is forced downward over a large horizontal area between the gas containing strata and oil bearing strata.
Abstract: A method and apparatus for and aggregates in a fluid medium. The present invention employs an ultrasonic device to efficiently breakup particle agglomerates by driving the ultrasonic signal over a small range of frequencies around the acoustic slow wave frequency of the saturated agglomerate. At this frequency, the fluid vibrates out of phase with the solid and is forced out through the pore structure in the agglomerate. This relative fluid motion to exert high viscous stresses at the particle-particle contact points which leads to fracture of the agglomerate and the redispersion of the individual particles. The apparatus includes a dispersing vessel containing aggregates of particles in a fluid, a sonic member for applying an ultrasonic signal in said dispersing vessel for separating the aggregates to form dispersed particles.
Type:
Grant
Filed:
October 30, 2000
Date of Patent:
June 18, 2002
Assignee:
Xerox Corporation
Inventors:
Robert J. Meyer, Christine J. Tarnawskyj
Abstract: Process intended for enhanced recovery of a petroleum fluid by combined injection of an aqueous phase saturated with acid gases. The process esentially consists in continuously injecting, into the oil reservoir, a mixture of an aqueous phase and of a gas at least partially soluble in the aqueous phase and at least partially miscible with the petroleum fluid, by controlling the ratio of the flow rates of the aqueous phase and of the gas so that the latter is always in a state of saturation or oversaturation at the bottom of the injection well(s). The aqueous phase saturated or oversaturated with gas comes into contact with the petroleum fluid present in the reservoir. The gas dissolved in the aqueous phase is at least partially transferred to the liquid hydrocarbon phase, thus causing swelling and viscosity reduction of this phase, which favors migration of the petroleum fluid towards a production zone.
Abstract: Soil, which is contaminated by one or more hydrophobic organic chemicals, can be cleaned or remediated using an aqueous composition with a surfactant prepared by reacting an alkenylsuccinic anhydride or acid with an amine acid or salt of an amine acid. The surfactant allows at least a portion of the hydrophobic organic chemical to be removed from the soil by becoming associated with the aqueous composition, which is then separated from the soil.
Type:
Grant
Filed:
October 14, 1999
Date of Patent:
December 4, 2001
Assignee:
The Lubrizol Corporation
Inventors:
Robert N. Jones, James H. Bush, Stuart L. Bartley, John J. Mullay, Gregory M. Mlachak
Abstract: A method of producing an oil reservoir having a gas cap and an oil column. A first injection fluid, such as water, is introduced into the reservoir at the gas-oil contact and gas and oil are simultaneously produced from the gas cap and oil column, respectively. A second injection fluid, such as water, may be introduced at a point in or below the oil column.
Abstract: An improved method for the recovery of hydrocarbons from a hydrocarbon deposit comprising the steps of introducing a diluent gas along a predominantly horizontal injection well drilled at the base of a hydrocarbon deposit; creating an initial communication path with a predominantly horizontal production well spaced laterally apart from the injection well; gradually enriching the diluent gas with a hydrocarbon solvent to produce a hydrocarbon solvent vapor which is saturated at reservoir conditions; continuously circulating the diluent gas and the saturated hydrocarbon solvent vapor through the hydrocarbon deposit; and producing mobilized hydrocarbons from the hydrocarbon deposit.
Abstract: For extracting a liquid (such as oil) from a porous medium, the liquid is subjected to pulses that propagate through the liquid flowing through the pores of the medium. The pulses cause momentary surges in the velocity of the liquid, which keeps the pores open. The pulses can be generated in the production well, or in a separate excitation well. If the pulses travel with the liquid, the velocity of travel of the liquid through the pores can be increased. The solid matrix is kept stationary, and the pulses move through the liquid. The pulses in the liquid can be generated directly in the liquid, or indirectly in the liquid via a localized area of the solid matrix.
Type:
Application
Filed:
April 9, 2001
Publication date:
August 30, 2001
Applicant:
PE-TECH Inc.
Inventors:
Brett Charles Davidson, Maurice Bernard Dusseault, Mikhail Boris Geilikman, Kirby Warren Hayes, Thomas James Timothy Spanos
Abstract: A method of stimulating coalbed methane production by injecting gas into a producer and subsequently placing the producer back on production is described. A decrease in water production may also result. The increase in gas production and decrease in water production may result from: (1) the displacement of water from the producer by gas; (2) the establishment of a mobile gas saturation at an extended distance into the coalbed, extending outward from the producer; and (3) the reduction in coalbed methane partial pressure between the coal matrix and the coal's cleat system.
Type:
Grant
Filed:
June 23, 1999
Date of Patent:
June 12, 2001
Assignee:
The University of Wyoming Research Corp.,
Abstract: A method of making surfactants from lignin is disclosed by reducing lignin in the presence of a metal oxide or iron based catalyst in an organic hydrogen donor solvent to produce lignin phenol and subjecting the lignin phenol to one or a combination of several reactions such as alkoxylation, alkylation, sulfonation, sulfation, alkoxysulfation, and sulfomethylation. The lignin surfactants so produced can be employed in a surfactant system to recover oil from underground formations.
Type:
Grant
Filed:
June 5, 2000
Date of Patent:
March 27, 2001
Assignee:
Texaco Inc.
Inventors:
Douglas Gene Naae, Lawrence Edward Whittington, Dan Edward Kieke
Abstract: In an underground oil reservoir, an injection well is completed low in the reservoir and a production well is provided having a horizontal leg completed relatively high in the reservoir and a vertical leg completed low in the reservoir. Water is injected with the vertical leg open and the horizontal leg closed, so that a displacement front advances in an under-riding manner between the wells and oil is produced through the vertical leg. Once the water break-through in the vertical leg occurs, it is closed and the horizontal leg is opened. A rising, horizontal, gravity-stable displacement front then advances upwardly toward the horizontal leg, through which oil is produced. The open horizontal leg acts as a low pressure sink to induce the horizontal displacement front to advance up toward it. This two-stage process is characterized by a good vertical and lateral sweep.
Abstract: For use in a field having a plurality of interspersed injection and production wells that extend to a mineral bearing formation, a system for extracting the mineral from the formation having a jet pump system for each production well, each pump system having a power fluid inlet and a production fluid outlet at the earth's surface, a bottom hole fluid inlet, a solvent reservoir at the earth's surface providing a source of liquid solvent and reservoir having connection to each of the injection wells by which solvent is conveyed to the mineral producing formation to produce a bottom hole reservoir of mineral laden bottom hole fluid, a power fluid reservoir at the earth's surface, a high pressure pump at the earth's surface connected between the power fluid reservoir and the power fluid inlet of each of the jet pump systems for moving power fluid through the jet pump systems to draw in bottom hole fluid that is mixed with the power fluid to provide production fluid that is moved to the earth's surface; and a mine
Abstract: A soil and groundwater decontamination system (10) and associated process are provided for soil and groundwater remediation. The system (10) and process utilizes both a physical or chemical reaction with the contaminants in a contaminated subsurface zone and extraction of the reaction end products and any remaining contaminants from the contaminated subsurface zone (100). In architecture, the soil and groundwater decontamination system (10) comprises an chemical product (12) that is introduced into an injection well (18). The injection well (18) is disposed into a passage provided in or adjacent to the contaminated subsurface zone (100) and allows the introduction of the chemical product (12) (and catalyst (24) if necessary) into the contaminated subsurface zone (100). The chemical product (12) reacts (physically or chemically) with contamination in the soil and groundwater and creates a reaction end product.
Abstract: A method is disclosed for recovering methane from a solid carbonaceous subterranean formation having a production well in fluid communication with the formation and an injection well in fluid communication with the formation. In the method an oxygen-depleted effluent, produced by a cryogenic separator is injected into the formation through the injection well. A first methane-containing gaseous mixture is recovered from the formation through the production well-during at least a portion of the time the oxygen-depleted effluent is being injected into the formation. The first methane-containing gaseous mixture has a first methane-desorbing gas volume percent. The injection of oxygen-depleted effluent is ceased and thereafter a second methane-containing gaseous mixture is recovered from the formation which has a second methane-desorbing gas volume percent which is less than the first methane-desorbing gas volume percent.
Abstract: A method and apparatus for operating a well which has a wellbore which passes into both an oil and gas production zone and a gas injection zone. An oil and gas stream is produced from the production zone through the wellbore to the surface where gas is separated from the oil. After production is shut-in, gas is mixed with a carrier fluid at the surface to form a dense mixture which, in turn, is flowed down the same wellbore and through a downhole auger separator wherein a portion of the gas is separated from the mixture. The separated gas is injected into the injection zone with the remainder of the mixture being returned to the surface. At the conclusion of the injection cycle, the well is returned to production and, if desired, the process is repeated.
Abstract: An improved concentrated surfactant formulation and process for the recovery of residual oil from subterranean petroleum reservoirs, and more particularly an improved alkali surfactant flooding process which results in ultra-low interfacial tensions between the injected material and the residual oil, wherein the concentrated surfactant formulation is supplied at a concentration above, at, or, below its CMC, also providing in situ formation of surface active material formed from the reaction of naturally occurring organic acidic components with the injected alkali material which serves to increase the efficiency of oil recovery.
Abstract: A gravity-drainage hydrocarbon recovery method is provided to produce oil and gas from subterranean formations. A substantially horizontal high-permeability web is created at the bottom portion of an oil reservoir. The web is connected to a production well. The high-permeability web is fabricated by conventional drilling, high-pressure water jet drilling, and high-power microwave fracturing. Primary oil recovery will benefit from this configuration in terms of improved volumetric sweep efficiency, delayed gas break through, increased oil production rate and overall oil recovery. This method is also used with secondary oil recovery for which a gas is injected into the upper portion of a reservoir. Oil is produced from the bottom portion of the reservoir. If economically warranted, high-permeability web is also implemented to the injection well.
Abstract: A hole in the earth for transferring geothermal energy from the earth around the hole to an energy carrier fluid which is introduced into the hole. The lower ends (7, 8) of at least two substantially vertically extending hole sections (2, 4) which have been used as wells for the recovery of oil or gas, are interconnected via an additional hole section (3).
Abstract: A method for increasing the production of methane from a subterranean carbonaceous formation by chemically stimulating the formation of additional free surface area or cleats in the organic constituents of the formation and by causing inorganically adsorbed methane to be released from contained clay-minerals to increase the rate of methane desorption from the formation by injecting an aqueous oxidizing solution containing at least one oxidant into the formation, and thereafter producing methane from the formation at an increased rate. Suitable oxidants include peroxide, ozone, oxygen, chlorine dioxide, sodium hypochloride, water soluble salts of hypochlorous acid, perchlorate, chlorate, persulfate, perborate, percarbonate, permanganate, nitrate and combinations thereof.
Abstract: A method for increasing the production of methane from a subterranean coal formation by chemically stimulating the formation of cleats in the formation to increase the rate of methane production from the formation by injecting an aqueous oxidant solution into the formation to stimulate the formation of cleats in the formation; and thereafter producing methane from the formation at an increased rate. Suitable oxidants include chlorine dioxide, metallic salts of perchlorate, chlorate, persulfate, perborate, percarbonate, permanganate, nitrate and combinations thereof.
Abstract: Disclosed is an electrokinetic soil decontamination system that uses special electrode wall configurations, treatment wall configurations, and a combination electrode/treatment wall. A special emplacement method for all the flowable wall materials is used and special wall material compositions are disclosed.
Type:
Grant
Filed:
December 13, 1996
Date of Patent:
June 22, 1999
Assignee:
E. I. du Pont de Nemours and Company
Inventors:
Ronald J. Griffith, Richard Claude Landis, Dale Steven Schultz
Abstract: A method for increasing the production of methane from a subterranean coal formation penetrated by an injection well and a production well by producing methane from the coal formation via the production well; passing a portion of the methane to a synthesis gas generation zone wherein at least a portion of the methane is reacted with an oxygen-containing gas to produce a mixture of carbon monoxide and hydrogen; passing a major portion of the mixture to a hydrocarbon synthesis zone wherein the carbon monoxide and hydrogen are reacted to produce heavier hydrocarbons and a tail gas comprising nitrogen and carbon dioxide; separating a major portion of the tail gas from the hydrocarbons and recovering the hydrocarbons as a product stream; injecting at least a portion of the tail gas into the coal formation through the injection well. The methane may be obtained from a single well or a plurality of wells operated to produce the methane by a huff and puff process.
Abstract: Disclosed is a process for removing contaminants from a contaminated area of the subsurface which comprises providing a borehole in the contaminated area; placing in the borehole a perforated riser pipe inside of which is situated a vacuum extraction pipe with an opening situated within the perforated riser pipe, wherein a packing is situated in a portion of the annular space between the vacuum extraction pipe and the perforated riser pipe; applying a vacuum to the vacuum extraction pipe to draw gases and liquid from the subsurface into the perforated riser pipe below the packing and from the riser pipe into the vacuum extraction pipe and transport both the gases and the liquid to the surface as a common stream; forming from the common stream a stream which is primarily liquid and a stream which is primarily gaseous; and removing contaminants from at least one of the liquid stream and the gaseous stream. Also disclosed is an apparatus for carrying out the disclosed process.
Type:
Grant
Filed:
June 7, 1995
Date of Patent:
January 20, 1998
Assignee:
Xerox Corporation
Inventors:
Richard A. Williams, Ronald E. Hess, Michael T. Salotti, John F. Thomasser, Scott M. Huber, Eliott N. Duffney, Alfonso R. Mancini
Abstract: A system extracts contaminated vapors from soil or other subsurface regions by using changes in barometric pressure to operate sensitive check valves that control air entry and removal from wells in the ground. The system creates an efficient subterranean flow of air through a contaminated soil plume and causes final extraction of the contaminants from the soil to ambient air above ground without any external energy sources.
Type:
Grant
Filed:
December 7, 1995
Date of Patent:
December 16, 1997
Assignee:
Lockheed Idaho Technologies Company
Inventors:
Jerry R. Weidner, Wayne C. Downs, Timothy G. Kaser, H. James Hall
Abstract: A method and apparatus for achieving in situ bioremediation of dissolved or dispersed organic contaminants in the groundwater phase at a contaminated site. The apparatus of this invention is configured to be used within an injection well of the type employed with known remediation techniques and enhances the biological treatment of soil contaminants in situ with microbes through achieving optimal levels of oxidizing agents within the soil. As such, the present invention is adapted to be employed in conjunction with conventional remediation systems to treat water-borne contaminants more efficiently. Importantly, the apparatus is also capable of delivering oxidizing agents in a manner that prevents or at least reduces the occurrence of biofouling of the injection and recovery wells.
Type:
Grant
Filed:
February 25, 1997
Date of Patent:
November 25, 1997
Assignee:
General Motors Corporation
Inventors:
Abdul Shaheed Abdul, Thomas Loughborough Gibson
Abstract: A soil remediation system (10) for removing contaminants (11) from a contaminated area (12) located in the vadose zone (13) of the earth and comprising multiplicity of stratigraphic zones, contaminants and compositions (26, 28), is disclosed. The system (10) comprises a first circulator (32) for circulating gas through the first zone (26) at a first volumetric rate and a second circulator (38) for circulating gas through the second zone (28) at a second volumetric rate to carry the contaminants in each respective zone (26, 28) to the surface of the earth (15). The system (10) includes a zero or low permeability membrane or layer (34) positioned between the first and second zone (26, 28) to control the commingling of the first and second volumetric flow rates so as to allow removal of contaminates in the first zone (26) independent of the removal of contaminates in the second zone (28).
Abstract: A method for increasing the production of methane from a subterranean coal formation by chemically stimulating the formation of cleats in the coal formation in order to facilitate removal of formation water, and increase the rate of methane production from the coal formation is disclosed. The method comprises injecting an aqueous oxidant solution into the coal formations to stimulate the formation of cleats in the coal formation; and thereafter producing methane from the coal formations at an increased rate. The aqueous oxidant solution comprises hypochlorite, metallic salts of hypochlorous acid, hydrogen peroxide, ozone, oxygen and combinations thereof.
Abstract: An enhanced oil recovery process comprises of the at least periodic introduction of (i) a non-condensible gas preferably selected from among carbon dioxide, nitrogen, methane or mixtures thereof, and (ii) an aqueous drive solution, preferably brine, into a reservoir formation. In this process, the half cycle of non-condensible gas injection, prior to aqueous drive fluid injection, measured in hydrocarbon pore volume is less than 0.25%. In this preferred embodiment, the non-condensible gas, e.g., carbon dioxide, and water, are simultaneously injected into the formation.
Type:
Grant
Filed:
May 8, 1996
Date of Patent:
June 3, 1997
Assignee:
Chevron U.S.A. Inc.
Inventors:
Chris E. Stevens, Steven D. McPherson, John R. Larson, Donnell R. Robie, Ronald K. Wackowski
Abstract: A method for the recovery of hydrocarbons from a reservoir of hydrocarbons including injecting a hydrocarbon solvent into the reservoir along with a displacement gas to mobilize hydrocarbons in the reservoir of hydrocarbons; and producing mobilized hydrocarbons from the reservoir of hydrocarbons. The hydrocarbon solvent is injected along one or more predominantly horizontal injection wells in the aquifer that are spaced from the production well or wells. The hydrocarbon solvent is a hydrocarbon solvent selected from the group consisting of ethane, propane, butane.
Abstract: A method is disclosed for recovering methane from a solid carbonaceous subterranean formation having a production well in fluid communication with the formation and an injection well in fluid communication with the formation. In the method an oxygen-depleted effluent, produced by a cryogenic separator is injected into the formation through the injection well. A first methane-containing gaseous mixture is recovered from the formation through the production well during at least a portion of the time the oxygen-depleted effluent is being injected into the formation. The first methane-containing gaseous mixture has a first methane-desorbing gas volume percent. The injection of oxygen-depleted effluent is ceased and thereafter a second methane-containing gaseous mixture is recovered from the formation which has a second methane-desorbing gas volume percent which is less than the first methane-desorbing gas volume percent.
Abstract: A method for treating a mixture of gaseous fluids within a solid carbonaceous subterranean formation. In some embodiments, the invention provides for the disposal of a strongly adsorbing gaseous fluid within the formation. In other embodiments, the invention provides a means for fractionating a mixture of gaseous fluids within the formation. In still other embodiments, the invention provides for the recovery of a raffinate from the formation which is enriched in relatively weaker adsorbing gaseous fluids. In still other embodiments, the invention provides for the recovery of methane from the formation.
Type:
Grant
Filed:
August 7, 1995
Date of Patent:
October 22, 1996
Assignee:
Amoco Corporation
Inventors:
Joseph J. Chaback, Dan Yee, Richard F. Volz, Jr., John P. Seidle, Rajen Puri
Abstract: This invention is an enhanced vapor extraction system and method for in-situ remediation of soils contaminated with volatile organic compounds, weathered organic compounds and residual organics. The system consists of air influx wells installed around the periphery of the contaminated zone, an air extraction well installed within the contaminated soil zone and a vacuum pump or suction blower pulling on the extraction well and creating an air circulation which flows from the influx wells through the pore spaces of the contaminated soil to the extraction well. The shear action of the flowing air strips the contaminants from the soil surfaces and pore spaces and entrains them into the air stream for later disposal. The improvement consists of increasing the air velocity through the system to increase shear action and so the rate of contaminant removal.
Abstract: An enhanced oil recovery process comprises of the at least periodic introduction of (i) a non-condensible gas preferably selected from among carbon dioxide, nitrogen, methane or mixtures thereof, and (ii) an aqueous drive solution, preferably brine, into a reservoir formation. In this process, the half cycle of non-condensible gas injection, prior to aqueous drive fluid injection, measured in hydrocarbon pore volume is less than 0.25%. In this preferred embodiment, the non-condensible gas, e.g., carbon dioxide, and water, are simultaneously injected into the formation.
Type:
Grant
Filed:
July 1, 1994
Date of Patent:
May 14, 1996
Assignee:
Chevron U.S.A Inc.
Inventors:
Chris E. Stevens, Steven D. McPherson, John R. Larson, Donnell R. Robie, Ronald K. Wackowski
Abstract: Disclosed is a process for removing contaminants from a contaminated area of the ground having a vadose zone and a water table, which comprises providing a borehole in the contaminated area to a depth below the water table; placing in the borehole to a depth below the water table a first perforated riser pipe; placing inside the first perforated riser pipe a second perforated riser pipe; placing inside the second perforated riser pipe a first vacuum extraction pipe with a bottom opening situated within the second perforated riser pipe; placing a second vacuum extraction pipe within the first perforated riser pipe but without the second perforated riser pipe; while introducing a gas into the second perforated riser pipe, applying a vacuum to the first vacuum extraction pipe and applying a vacuum to the second vacuum extraction pipe to draw gases and liquid from the soil into the first vacuum extraction pipe and the second vacuum extraction pipe and transport both gases and liquid to the surface as two-phase co
Type:
Grant
Filed:
October 20, 1994
Date of Patent:
November 7, 1995
Assignee:
Xerox Corporation
Inventors:
Alfonso R. Mancini, Richard A. Williams
Abstract: An apparatus and process for separating and producing gas and liquid from a subterranean production zone via a well in fluid communication with the zone. After separation in the well, the gas is produced to the surface, compressed, and injected into an injection zone which is also in fluid communication with the well. The liquid is pumped to a production facility at the surface.
Abstract: The invention is directed at a method and apparatus for producing liquids, namely hydrocarbons, from a subterranean formation using a well having a collecting wellbore located at least partially within the formation.
Abstract: A method for treating a mixture of gaseous fluids within a solid carbonaceous subterranean formation. In some embodiments, the invention provides for the disposal of a strongly adsorbing gaseous fluid within the formation. In other embodiments, the invention provides a means for fractionating a mixture of gaseous fluids within the formation. In still other embodiments, the invention provides for the recovery of a raffinate from the formation which is enriched in relatively weaker adsorbing gaseous fluids. In still other embodiments, the invention provides for the recovery of methane from the formation.
Type:
Grant
Filed:
April 1, 1994
Date of Patent:
August 8, 1995
Assignee:
Amoco Corporation
Inventors:
Joseph J. Chaback, Dan Yee, Richard F. Volz, Jr., John P. Seidle, Rajen Puri
Abstract: A method for the recovery of hydrocarbons from a hydrocarbon deposit overlying an aquifer, including injecting a hydrocarbon solvent in the vapour phase into the aquifer to mobilize hydrocarbons in the hydrocarbon deposit; and producing mobilized hydrocarbons from the hydrocarbon deposit. Mobilized hydrocarbons are produced from the aquifer, and the hydrocarbon solvent is injected along one or more predominantly horizontal injection wells in the aquifer that are spaced from and alternate with the production well or wells. The hydrocarbon solvent is a hydrocarbon solvent selected from the group consisting of ethane, propane, butane.
Type:
Grant
Filed:
November 9, 1993
Date of Patent:
April 18, 1995
Assignee:
University Technologies International Inc.
Abstract: Processes are disclosed for separating an oxygen-containing gas into oxygen-enriched and oxygen-depleted streams. The oxygen-depleted stream is injected into a methane-containing solid carbonaceous subterranean formation to produce a methane-containing gaseous mixture. The oxygen-enriched stream is reacted with a stream containing an oxidizable material which can be the methane-containing mixture.
Abstract: A method of recovering methane from a solid carbonaceous subterranean formation having a production well in fluid communication with the formation and an injection well in fluid communication with the formation, comprising the steps of passing a gaseous fluid containing at least 60 volume percent nitrogen and at least 15 volume percent oxygen through a membrane separator to produce an oxygen-depleted effluent, pressurizing the oxygen-depleted effluent to a pressure above a reservoir pressure of the solid carbonaceous subterranean formation, injecting the oxygen-depleted effluent into the formation through the injection well, and recovering a fluid comprising methane through the production well.
Abstract: A method is disclosed for increasing the production of methane from a solid carbonaceous subterranean formation having a standard initial production rate of a methane-containing gas of X standard cubic feet per unit time. The method comprises the steps of injecting an inert methane-desorbing gas into the formation; terminating injection of the methane-desorbing gas; and thereafter recovering greater than X standard cubic feet per unit time of a methane-containing gas from the formation. In some embodiments, a number of well systems exceeding the number of available inert gas production and injection units can be operated in accordance with the present invention to yield greater methane-containing gas production than would be obtained if the available injection systems were dedicated continuously to particular well systems.
Abstract: A method of reducing, preferably preventing, precipitation of asphalt from crude oil. In one aspect, crude oil is contacted in the borehole with at least one N,N-dialkylamide of a fatty acid having 8 to 22 carbon atoms. In an second aspect, precipitation is reduced during miscible flooding in an EOR process by adding to the flooding solvent at least one N,N-dialkylamide of a fatty acid having 8 to 22 carbon atoms.
Type:
Grant
Filed:
February 8, 1993
Date of Patent:
February 14, 1995
Assignee:
Buckman Laboratories International, Inc.
Abstract: A method for reducing the inert gas fraction volume percent present in a methane-containing mixture produced by injecting an inert gas into a solid carbonaceous subterranean formation is disclosed. The method reduces the inert gas fraction by suspending the injection of the inert gas or by reducing a rate of injection of the inert gas. Additional methods are disclosed in which the inert gas volume percent of a gaseous mixture produced from more than one well can be maintained below the inert gas volume percent present in a gas obtained from at least one of the wells.
Abstract: A method is disclosed for using a pressure swing adsorption separator system to provide an oxygen-depleted gaseous effluent for injecting into a suitable solid carbonaceous subterranean formation, such as a coalbed, to enhance the recovery of methane from the formation.
Abstract: A method of recovering hydrocarbons from a reservoir under an active waterflood or water drive by injecting a recovery fluid comprising carbon dioxide or nitrogen under immiscible conditions, allowing the recovery fluid to soak, and producing the recovery fluid and formation fluids under conditionally miscible or miscible conditions after pressure has sufficiently increased in the wellbore area.
Abstract: The present invention refers to a process for creating in an aquifer an oxidation and precipitation zone (or a reduction zone) between a number of injection wells arranged around one or more extraction wells for purified water. The zone desired is created intermittently between each pair of adjacent injection wells by (i) introducing oxygen, oxygen-containing gas or an oxygen-releasing substance (or an oxygen-consuming substance) into the water in both wells and (ii) pumping the water in one well from below upwards while pumping the water in the other well from above downwards, whereby a circulation circuit is formed in the aquifer between the wells. A device for carrying out said process comprises an outer tube (1), sealing means (2), an inner tube member (3), a transversal wall (4) with a central opening, an elongation tube (5), an inner flow pipe (6) and conduits (7,8) for supply of air.
Abstract: The invention is a method for increasing the effectiveness of steam or carbon dioxide foaming operations for improving conformance during steam or carbon dioxide floods by adding to the surfactant foaming solution an alcohol having about 8 to about 20 carbon atoms in a concentration such that the ratio of alcohol to surfactant in the foaming solution is between about 1:6 and about 1:2.