Abstract: A process for decreasing the CO.sub.2 content of hydrocarbon gas by injecting a hydrocarbon gas containing CO.sub.2 into a water bearing zone of an underground formation and producing hydrocarbon gas from a collection point in the underground formation removed from the injection point.

Abstract: A method of producing hydrocarbonaceous liquids and gases from subterranean kerogen-containing oil shale formations comprising (a) penetrating the oil shale deposits with at least two well bores; (b) fracturing the oil shale deposits in a lower vertical portion thereof; (c) igniting the hydrocarbonaceous deposit; (d) introducing through the first well bore a free oxygen-containing gas to the ignited point of the oil shale deposit to effect thermal decomposition of the hydrocarbonaceous material therein and to propagate a combustion zone through the fractured communication area and the second well bore, thereby forming a region of combusted shale between the first well bore and the second well bore; (e) allowing the combustion to continue until a sufficient volume of combusted shale has been formed; (f) then jetting an aqueous liquid into and through the combusted shale zone to remove the mineral residue remaining after combustion; (g) positioning conventional explosives in the oil shale deposit in the vicinit

Abstract: A fluid injection induced oil recovery process wherein fluid is injected into a formation via a plurality of fluid injection wells and is produced from the formation via a plurality of production wells, and excessive flow and channeling through a "thief" region between one injection well and one production well is controlled by successively (1) shutting in the one injection well and operating the one production well for a first period of time and (2) operating the injection well and shutting in the production well for a second period of time. This sequence is repeated as many times as desired. The sequence can be modified by adding the additional step of (3) operating both wells for a third period of time. This alternative sequence is also repeated as many times as desired.

Abstract: The vertical conformance of a steam drive process is improved and steam override reduced by penetrating the zone between one injector and one producer, with an infill well which is in fluid communication with the bottom half of the formation, and producing petroleum from the infill well after steam channeling has occurred at the production well. After the water cut of the fluids being produced from the infill well reaches 95 percent, the infill well is converted from a producer to an injector and hot water is injected into the lower portion of the formation via the infill well and fluids are produced from the production well. By this means, oil is recovered from the lower portions of the formation adjacent the production well. After water breakthrough occurs at the production well, steam is injected into the infill well and fluids are recovered from the production well.

Abstract: Thermal oil recovery processes employing the injection of steam and/or hot water for mobilizing viscous petroleum sweep only a small fraction of the formation between the wells because of override, underride, or channeling resulting in poor vertical conformance, as well as poor horizontal conformance of the swept portion of the formation. Both vertical and horizontal conformance are improved significantly if steam is injected into a formation until channeling has begun, after which steam injection is terminated and an aqueous fluid is injected into the formation, which has a viscosity essentially the same as water and contains an emulsifying agent capable of forming a viscous emulsion in the portions of the formation where override, underride or channeling has occurred. After a small slug of emulsifying fluid has been injected, steam injection is resumed and as a consequence of the emulsion plug, moves into portions of the formation from which oil would not be recovered if the emulsion had not been injected.

Abstract: The vertical or both vertical and horizontal conformance of a steam drive process is improved and steam override reduced by penetrating the zone between one injector and one producer, with one or more infill wells in fluid communication with the bottom half or less of the formation, and producing petroleum from the infill well after steam channeling has occurred at the production well. After the water cut of the fluids being produced from the infill well reaches 95 percent, the infill well is converted from a producer to an injector and steam is injected into the infill well and fluids are recovered from the production well. When one infill well is employed in a more or less aligned arrangement between injection and production wells, the vertical conformance is improved. When one or more infill wells are positioned in an offset or nonaligned arrangement relative to each injector and producer, conformance in both the horizontal and vertical planes is improved.

Abstract: The vertical conformance of a steam drive process is improved and steam override reduced by penetrating the zone between one injection well and one producing well, with an infill well which is in fluid communication with the bottom half or less of the formation, and producing petroleum from the infill well after steam channeling has occurred at the production well; then converting the infill well from a producer to an injector and injecting steam into the lower portion of the formation via the infill well and recovering fluids from the production well. Two separate communication paths are established, one between the surface and the upper half or less of the formation, and one between the bottom half or less of the formation in the producing well, or in the infill well, or injection well, or combination of two or more thereof.

Abstract: The vertical conformance of a steam drive process is improved and steam override reduced by penetrating the recovery zone between one injection well and one producing well, with at least one infill well which is in fluid communication with no more than the bottom half of the formation. Steam or a mixture of steam and hydrocarbon is injected into the injection well and fluids including oil are recovered from the producing well until live steam production occurs at the producing well. Petroleum production is then begun at the infill well and continued until the water cut of the fluids being produced from the infill well reaches 95 percent. The infill well is converted from a producer to an injector and hot water or cold water followed by hot water is injected into thelower portion of the formation via the infill well and fluids are produced from the production well. By this means, oil is recovered from the lower portions of the formation between the infill well and the production well.

Abstract: The vertical conformance of a steam drive process is improved and steam override reduced by penetrating the zone between one injector and one producer, with an infill well located between the injector and producer which is in fluid communication with no more than the bottom half of the formation. Steam is injected into the injection well in the first phase with production of fluids from the upper 1/3 or less of the formation via the production well. A separate flow path in communication with the bottom 1/3 or less of the formation is provided in the producing well, and is used during the first phase for push-pull treatment of the formation with solvent and steam or hot water.

Abstract: This invention relates to novel leaching methods and apparatus for recovering minerals such as ores, high viscosity oil, and the like, from the subsurface earth formation. More specifically, the formation is penetrated by a plurality of mine shafts or large-diameter boreholes which are spaced apart as a function of the lithological characteristics of the formation. Thereafter, a suitable leaching fluid such as a liquid solvent, steam, free hydrogen, or carbon dioxide is injected into the formation through a plurality of drill holes radially extending from the lower portions of the shafts.In a particular technique for recovering high viscosity oil, the formation is initially subjected to a sequence of "soaking" cycles, wherein fluid is injected into the formation during separate discrete time periods, and wherein dissolved minerals or reduced viscosity oil is drained from the drill holes during the interval following each injection period.

Abstract: A method of extracting oil from an underground bed of an oil-bearing mineral. The method comprises introducing a plurality of conduits into a first, lower part of the bed. Each conduit is spaced from its neighbors and includes a relatively coarse filter at its lower end and contains a relatively fine filter and a lift pump. A first conduit of the plurality of conduits extends to a depth less than the depth of its neighbors. The pressure in the first conduit is reduced. A solvent for the oil is introduced into those conduits at ambient pressure so that the solvent is drawn towards the first conduit and forms a flow path in the bed as it is drawn to the first conduit. The oil-solvent solution is pumped from the first conduit and the space left in the first area after extraction of the oil is filled with water.

Abstract: A process for recovering oil from a heterogeneous subterranean reservoir having strata of widely varying permeability by injecting therein via a well a slug of a micellar solution followed by an aqeuous drive fluid wherein, at some time prior to the injection to all of the slug of the micellar solution, there is injected into the reservoir one or more aqueous solutions of reagents that react in the reservoir to form a plugging material, one of which reagents contains a polyvalent cation. After the plugging material has formed, the well is produced to remove from the reservoir the unreacted reagent containing a polyvalent cation which polyvalent cation would otherwise react with and reduce the efficiency of the subsequently injected micellar solution.

Abstract: A method for the in-situ recovery of low API gravity oils or bitumen from subterranean hydrocarbon-bearing formations wherein the recovery is optimized by the injection of a mixture of an oxygen-containing gas and steam until the recovery efficiency declines, followed by the injection of a mixture of light hydrocarbon and steam, under operating conditions that may utilize pressurization and drawdown cycles.

Abstract: A multi-phase heated fluid process which avoids heated fluid breakthrough, is used to continually produce subsurface hydrocarbons, utilizing two commmunicating wells in a process comprising:Simultaneous injection of said heated fluid into said wells until substantial mobilization of hydrocarbons within a zone surrounding said wells is obtained; one well is shut in while production is commenced in the other well;Preferably a final phase where sufficient heated fluid at relatively restricted rates is continually injected into said one well to provide driving force for continual production in said other well, without interruption, once production has commenced.

Abstract: A method of improving the sweep efficiency and increasing oil recovery of miscible flooding without reducing injectivity of the injection wells. Two sets of wells are used with one set being drilled between the other sets. The interwell area of a reservoir is pretreated by injecting a permeability-reducing agent (preferably a polymer) through said first set of wells. The polymer enters the more permeable zones and partially plugs them, both near and away from the wellbore. Thereafter, the injection or first set of wells are converted to producing wells. After the step of reducing the permeability contrast of the heterogeneous reservoirs, a miscible slug, that may or may not be preceded by a controlled salinity preflush, is injected into the second set of wells. There is no reduction in injectivity of the miscible injection wells, becuse no permeability-reducing agent has been injected therethrough.

Abstract: Disclosed is an oil recovery method especially useful for recovering viscous oil from thick formations including tar sand deposits. The method comprises several phases which accomplish efficient recovery of the viscous oil from the formation with good vertical and horizontal sweep conformance or effectiveness. The first phase may utilize as few as two spaced apart wells, one for fluid injection and one for oil production and an oil recovery method such as injecting steam or a mixture of air and steam for low temperature, controlled oxidation is a preferred fluid for use in the first phase. After fluid breakthrough at the production well occurs, the producer of the first phase is converted to an injection well and one or more new production wells outside of the pattern swept by the injected fluid are completed in the oil formation. Thermal recovery fluids are then injected into two wells with the displacement moving in the direction of the new production wells.

Abstract: Disclosed is method for treating a high permeabiity communication channel between wells for use in a viscous oil recovery method to stabilize fine particulate matter present in the communication channel to prevent movement of fine particles during the oil recovery process. The communication channel is formed by fracturing or sweeping with air followed by introducing a viscous oil displacing medium such as a solvent or steam to desaturate the previously fractured or air swept zone in the formation, converting it into a high permeability channel between wells. In order to stabilize the fine grain sand and other minerals present in the communication channel to prevent migration thereof which results in loss of permeability of the communication channel, the channel is treated with a hydroxy aluminum solution and allowed to age for a period of time sufficient to form crystalline aluminum hydroxide which cements the grains together while maintaining permeability of the communication channel.

Abstract: Heavy or viscous oils may be recovered from subterranean deposits by one or more wells each of which is provided with at least two separate communication means from the surface of the earth, one in fluid communication with the upper part of the formation and the other well being in fluid communication with the lower part of the formation, each of said communication means being completed so as to permit injection of steam or mixtures of steam and other materials into the formation and production of heated viscous petroleum therefrom. A relatively impermeable barrier is formed between the portions of the formation where the communication is established, oriented horizontally and extending some distance into the formation. The oil recovery process comprises several separate phases of operation.

Abstract: Heavy or viscous oils may be recovered from subterranean deposits by one or more wells each of which is provided with at least two separate communication means from the surface of the earth, one in fluid communication with the upper part of the formation and the other well being in fluid communication with the lower part of the formation, each of said communication means being completed so as to permit injection of steam or mixtures of steam and other materials into the formation and production of heated viscous petroleum therefrom. The oil recovery process comprises several separate phases of operation. In the first, steam is injected into the formation using both communication means simultaneously for a period of time followed by a soak period if desired, followed by production of heated oil from both parts of the formation using both communication means simultaneously.

Abstract: Process for the gasification of coal in situ comprising driving shafts or tunnels into a coal seam, injecting air into the bore holes to ignite and burn the coal to raise its temperature ceasing the flow of air when the coal is hot enough to support the endothermic water gas reaction, and injecting steam into the hot coal formation, such steam preferably being preheated by the flue gases taken from the same end of the bore holes where the air was injected, and recovering product gases, including carbon monoxide and hydrogen, and also product oil, exiting the tunnel at the other end of the bore holes. When the temperature of the coal drops during injection of steam to a level which will just permit combustion, the steam flow is stopped, and the cycle is repeated by air injection and flue gas removal at the front end of the bore holes, and through the tunnel connected therewith. This cyclic process is repeated until the entire mass of coal within the area encompassed by the bore holes is exhausted.

Abstract: In the oil-bearing formation wherein primary production has been exhausted and secondary recovery by waterflooding is exhausted or about exhausted, the residual brine is removed by progressive displacement. In this displacement a centrally disposed injection well or, preferably, lineal injection wells are utilized for the initial injection of preflush fluid with the immediately adjacent production and/or injection wells being shut in. After a specified slug of preflush has been injected, a series of chemical slugs is injected followed by drive fluid. After displacement of the residual brine has been effected out past the adjacent shutin wells, as evidenced by the arrival of the preflush, they are utilized as production wells. After oil sweep to these wells is complete, they are used as injection wells and the procedure is moved another step outward.

Abstract: A method of in situ solution mining is disclosed in which a primary leaching process employing an array of 5-spot leaching patterns of production and injection wells is converted to a different pattern by converting to injection wells all the production wells in alternate rows.

Abstract: The present invention relates to an improved method for the solution mining of a mineral from a subterranean formation. More specifically, the invention relates to an improved method which enhances significantly the recovery of the mineral from a subterranean formation via solution mining. The improvement comprises switching a well which initially functions as a producer to an injector and vice versa after oxidant breakthrough has occurred at a production well.

Abstract: A method for producing geothermal energy and minerals from subterranean high temperature and high salinity water reservoirs by injecting low salinity water at ambient surface temperature into the reservoir through a well bore, allowing the injected water to become heated in the reservoir and then producing water through the well bore to the surface for use as a source of energy and, optionally, minerals. Simultaneously with the employment of certain wells for injection-production cycles, other wells may be employed predominantly for injection of water to displace heat and in-situ well brines to well bores which produce such water and brines to the surface for utilization of their heat energy and dissolved minerals.

Abstract: A method is provided for recovering heavy oil from an underground tar sand reservoir by injecting steam into an injection well penetrating the reservoir sufficiently to fracture the tar sand and provide passage for the steam through the tar sand to a production well piercing the tar sand reservoir. Steam is provided at sufficient heat to mobilize heavy oil from the permeated tar sand and a pressure sufficient to maintain competency of the formation to permit continued flow from the injection well to the production well. Injection of surfactant into the tar sand reservoir is used to produce a condensible foam which aids in maintaining back pressure on the injected steam within the tar sand reservoir to maintain the competency of the formation and to cause further permeation of the formation by the steam. Foam can be produced of strength sufficient to permit pressure to be applied in the tar sand reservoir capable of further fracturing the reservoir.

Abstract: An improved steam soak process recovers viscous oil from a reservoir containing a relatively steam impermeable oil-rich layer above a relatively steam permeable water-rich layer. Steam is injected at a rate and volume that displaces an oil bank into the water layer. The cooling of the oil bank impedes the flow of water so that, during the production cycle, the rate of oil recovery is increased.

Abstract: This application discloses a process for accomplishing in situ retorting of coal, or a similar hydrocarbon by constructing a substantially impervious retorting area, and then fragmenting the coal to provide a substantially homogeneous, porous mass. After pyrolysis due to the introduction of oxygen-containing gas at one portion and withdrawal of oil and gas at another portion, the direction of gas flow is reversed to convert the char into a relatively high B.T.U. gas product.

Abstract: A process for removing methane from a subterranean coal deposit. A carbon dioxide-containing fluid is introduced into the coal deposit through an injection well and held therein for a period sufficient to enable a substantial amount of methane to be desorbed from the surfaces of the coal deposit. Following the hold period, the injected carbon dioxide-containing fluid and desorbed methane are recovered through a recovery well or wells spaced from the injection well. The process is repeated until sufficient methane has been removed to enable safe mining of the coal deposit.

Abstract: In producing shale oil from a relatively permeable leached zone within a subterranean oil shale deposit, hot aqueous fluid is flowed between wells along paths which are vertically varied. An initial flow between near-bottom injection and production locations within the leached zone is varied by steps inclusive of producing fluid from a near-top location and injecting fluid into the initial production location.

Abstract: A method for recovering low-gravity viscous oils and bitumen hydrocarbons from a subterranean hydrocarbon-bearing formation by injecting thereinto a hydrocarbon solvent saturated with a gas, and thereafter establishing a thermal sink in the formation, followed by a soak period, and production of the hydrocarbons therefrom.

Abstract: Viscous petroleum may be recovered from viscous petroleum-containing formations including tar sand deposits by contacting the formation with a heated multiple-component solvent for the petroleum. At least one solvent component is normally gaseous material such as methane, ethane, propane or butane and at least one component is normally liquid, such as pentane and higher molecular weight hydrocarbons. The solvent mixture is heated to a temperature in excess of ambient temperature, and preferably from 100.degree. to 500.degree. F. prior to injection into the formation. The multiple solvent is introduced under sufficient pressure that it is substantially all liquid at the injection conditions. Recovery of petroleum and solvent may be from the same well as is used for injection or from a remotely located well.

Abstract: Coal liquids and gases are recovered from a thick underground coal seam by drilling one or more boreholes from the earth's surface into the lower part of the seam, burning out the coal over a limited area near the bottom of the seam, collapsing the overlying coal to form a rubblized zone extending vertically to a point near the upper boundary of the seam, driving a flame front vertically through the rubblized zone to liberate hydrocarbon liquids and produce gases, and recovering the liquids and gases from the rubblized zone.

Abstract: A process is provided in which hydrocarbon gas containing CO.sub.2 is injected into an oil containing reservoir as an aid in recovering oil from the reservoir. Oil can be produced from at least one production well in said reservoir while hydrocarbon gas containing less CO.sub.2 than the injected mixture of hydrocarbon gas and CO.sub.2 can be recovered from production wells other than the oil producing well. Backflowing of the injection well produces a gas containing more CO.sub.2 than the gas originally injected. The method provides an in situ separation of CO.sub.2 from hydrocarbon gas.

Abstract: An improved process for decreasing the permeability of a subterranean oil-bearing formation which comprises injecting an aqueous surfactant solution containing a chemically crosslinkable, water-dispersible polymer which prevents the surfactant from foaming until it is in the formation and after the polymer breaks down due to heat in the formation caused by steam which is used to carry the aqueous solution into the formation. In accordance with one embodiment, gelled or ungelled cellulose ether polymers in an aqueous surfactant solution are injected with steam into the more permeable or more depleted portions of a subterranean oil-bearing formation to produce a selective blocking due to the formation of foam in the more permeable sections of the formation which forces the remaining injection steam to produce oil from less depleted portions of the formation.

Abstract: High level sonic energy is introduced at the head of an oil well casing and transmitted through the gaseous column formed in the casing down to oil bearing strata from which oil is being extracted. The sonic energy is transmitted into this strata either through the opening in the bottom of the casing and/or apertures in the casing wall, the sonic energy operating to heat the oil particles so as to reduce their viscosity and to induce the migration of oil particles from the oil bearing strata, as well as to clear the interstices of the formation of flow impeding particles, thereby augmenting the flow of oil in the well. The basic process is enhanced by heating the gas within the casing and/or pressurizing the gas.

Abstract: Disclosed herein is a method for recovering oil from a subterranean oil-bearing formation in which adjacent wells are subjected to steam stimulation to create a zone around each well which is initially heated to approximately steam temperature and which has a high water saturation following steam injection and oil production. Subsequently, a fluid having a relatively high electrical conductivity, such as a brine solution, is injected into the heated zone around the wells. Preferably the injected volume of high conductivity fluid is sufficient to displace the steam condensate from the zone and to fill the zone with the high conductivity fluid. The wells are then completed as electrodes and current is passed through the formation to heat the oil which was not heated to any significant amount by the steam. Following one or more cycles of steam stimulation and electrical heating, additional oil is recovered from the formation, preferably by line-drive steam displacement or by pattern steam flooding.

Abstract: A liquid aquifer energy storage method by which hot water is collected and stored in underground aquifers during the summer months and made available for heating during winter months. The liquid aquifer energy storage method also allows for the storage of cold water during the winter months for use in cooling during the summer months. The liquid aquifer energy storage method includes heating water and hot and warm zones within the aquifer or aquifers for storage of hot and warm water, respectively. Additionally, the method includes cooling water and cold and cool zones in the aquifer or aquifers for storage of cold and cool water.