Abstract: Methods and apparatus relate to recovering petroleum products from underground reservoirs. The recovering of the petroleum products relies on introduction of heat and solvent into the reservoirs. Supplying water and then solvent for hydrocarbons in direct contact with combustion of fuel and oxidant generates a stream suitable for injection into the reservoir in order to achieve such thermal and solvent based recovery.

Abstract: A method for treating a wellbore in a hydrogen sulfide-containing formation that includes injecting a first slug in the wellbore, the first slug comprising: at least one of primary amine and ammonia; and a base fluid; injecting a second slug in the wellbore, the second slug comprising: a triazine scavenger; and a base fluid; and allowing the triazine scavenger to react with the hydrogen sulfide is disclosed.

Abstract: A method of in-situ processing of a subterranean oil shale formation to produce hydrocarbons comprising contacting the oil shale with (i) a carbon monoxide/water mixture or (ii) a carbon monoxide/water/hydrogen mixture together with at least one liquefaction promoter, under pressure and heat to produce hydrocarbons.

Abstract: A flow rate control valve, wherein the flow rate control valve is provided with a first circular tube section having first and second ports formed on a body forming the flow rate control valve, and also with a plate section mounted to the upper part of the first circular tube section through a mounting section. The plate section is provided to only one end side of the first circular tube section, is supported on the mounting section in a cantilever manner, and is formed flat.

Abstract: A cyclic remediation process to restore oil recovery from a primary oil production well that has watered off from bottom water encroachment (cone or crest) whereby: (a) the primary oil production well has a produced water cut in excess of 95% (v/v); (b) the oil is heavy oil, with in-situ viscosity >1000 cp; wherein said process includes: (c) injecting a steam slug with a volume of 0.5 to 5.0 times the cumulative primary oil production, with steam volumes measured as water volumes; (d) shutting in the well for a soak period, after the steam injection is complete; and (e) producing the well until the water cut exceeds 95%.

Abstract: Combustion gases with relatively high levels of carbon dioxide (CO2), steam, and/or hot water, may be used to improve recovery of heavy hydrocarbons from geologic formations and/or from surface mined materials. These gases reduce the viscosity and/or increase hydrocarbon extraction rates through improvements in thermal efficiency and/or higher rates of heat delivery for a given combustor an capital investment. Such high water/CO2 content combustion gases can be formed by adding water to combustion gases formed by burning fuel. The pressure to inject the combustion gases and extract heavy hydrocarbons may be provided by diverting high pressure expanded gases from wet combustion in a gas turbine, or by reducing the pressure drop across a turbine and using the expanded hot gases for extraction.

Abstract: A method of treating concentrated produced water derived from a steam assisted gravity discharge oil recovery process is described. The method includes utilizing a double drum dryer to dry a concentrated slurry and produce a dried concentrate for deposition in a landfill.

Abstract: A method for treating a karsted formation containing heavy hydrocarbons and dolomite includes providing heat to at least part of one or more karsted layers in the formation from one or more heaters located in the karsted layers. A temperature in at least one of the karsted layers is allowed to reach a decomposition temperature of dolomite in the formation. The dolomite is allowed to decompose and at least some hydrocarbons are produced from at least one of the karsted layers of the formation.

Abstract: A SAGD system including a string defining an axial flow channel and an annular flow pathway, a fluid access structure between the axial flow channel and the annular flow pathway, and a valve disposed within the annular flow pathway. The valve being selectively closable to selectively inhibit annular flow in an uphole direction. A method for treating a SAGD formation.

Abstract: A method for treating a hydrocarbon containing layer in a subsurface formation includes forming a plurality of substantially vertical fractures in the formation at selected intervals along a length of at least one production wellbore positioned substantially horizontally in the hydrocarbon containing layer. Heat is provided from a plurality of heaters to the hydrocarbon containing layer such that at least some hydrocarbons in the hydrocarbon containing layer are mobilized. At least some of the plurality of heaters are positioned substantially horizontally in the hydrocarbon containing layer. At least some mobilized hydrocarbons are produced through at least one production wellbore.

Abstract: An apparatus for combustion steam generation is provided, which includes a combustion chamber having an inlet end and an outlet end; a manifold at the inlet end configured to introduce a fuel and an oxidizer into the combustion chamber; an outer casing defining a coolant chamber between the outer casing and the combustion chamber; and a plurality of converging coolant inlets for conducting coolant from the coolant chamber into the combustion chamber at or near the outlet end of the combustion chamber. The converging coolant inlets are radially disposed around the combustion chamber and preferably configured to produce a converging-diverging nozzle from the coolant conducted into the combustion chamber. The device may be used in systems and methods for enhanced recovery of subterranean hydrocarbons, by deployment into and operation in a wellbore, where the produced steam and combustion gases are injected into a hydrocarbon formation to enhance hydrocarbon recovery.

Abstract: A method is proposed for heating a hydrocarbons reservoir, comprising the provision of an installation comprising: a first wellbore equipped with an injection string fitted with an adjustable choke and an extraction string fitted with an adjustable choke, a set of sensors, intended to measure physical variables, an automatic device making it possible to control and monitor the operation of the installation; the circulation of steam from one string to the other; the control of the steam injection flow rate in function of a target value; the keeping of a set of physical variables within a predetermined range of values by continuous action of the automatic device on the choke of the injection string, and on the choke of the extraction string.

Abstract: The present disclosure is generally directed to systems that are used for reclaiming components of wellbore cuttings material. In one illustrative embodiment, a system is disclosed that includes, among other things, a dryer that is adapted to receive a drill cuttings mixture that includes drilling fluid and cuttings material, the dryer being further adapted to treat the drill cuttings mixture by drying the cuttings material below a preselected moisture content level. The system also includes a moisture sensor that is adapted to sense a moisture content of the cuttings material after it is dried by the dryer, and a cuttings reinjection system that is adapted to reinject the dried cuttings material into a well bore. Additionally, the system includes a conveyor system that is adapted to convey the dried cuttings material to the cuttings reinjection system, wherein the conveyor system includes, among other things, a positive pressure pneumatic conveying apparatus.

Abstract: A method of producing oil which begins by drilling, casing and inserting a tubing string in a wellbore. The method then perforates both an upper portion and a lower portion of the casing to establish communication between the wellbore with a upper horizontal fracture and a lower horizontal fracture. A retrievable packer or a seal assembly is inserted horizontally between the tubing string and the casing and vertically between the upper horizontal fracture and the lower horizontal fracture for heat isolation. Steam is then injected into the wellbore both into the upper horizontal fracture and the lower horizontal fracture. Heavy oil is then produced from the lower horizontal fracture while injecting steam into the upper horizontal fracture.

Abstract: A gas generator is provided with a combustion chamber into which oxygen and a hydrogen containing fuel are directed for combustion therein. The gas generator also includes water inlets and an outlet for a steam and CO2 mixture generated within the gas generator. The steam and CO2 mixture can be used for various different processes, with some such processes resulting in recirculation of water from the processor back to the water inlets of the gas generator. In one process a hydrocarbon containing subterranean space is accessed by a well and the steam and CO2 mixture is directed into the well to enhance removability of hydrocarbons within the subterranean space. Fluids are then removed from the subterranean space include hydrocarbons and water, with a portion of the hydrocarbons then removed in a separator/recovery step. The resulting hydrocarbon removal system can operate with no polluting emissions and with no water requirements.

Abstract: A method of creating a network of fractures in a reservoir is provided. The method includes designing a desired fracture network system, and determining required in situ stresses to create the desired fracture network within the reservoir. The method further includes designing a layout of wells to alter the in situ stresses within the stress field, and then injecting a fracturing fluid under pressure into the reservoir to create an initial set of fractures within the reservoir. The method also includes monitoring the in situ stresses within the stress field, and modifying the in situ stresses within the stress field. The method then includes injecting a fracturing fluid under pressure into the reservoir in order to expand upon the initial set of fractures and to create the network of fractures. A method for producing hydrocarbons from a subsurface formation is also provided herein, wherein a fracture network is created from a single, deviated wellbore production.

Abstract: A method of determining a permeability profile of a heavy-oil bearing formation includes pre-heating of the formation by circulation of steam in a well, creating an excessive pressure inside the well during the pre-heating stage, stopping circulation of steam in the well, measuring temperature along a well bore of the well using distributed temperature sensors, wherein the measuring is performed from a moment at which steam circulation stops until a thermally stable condition is achieved, creating a conductive heat exchange model relating a quantity of steam penetrated into the formation to a local permeability of the formation, the model being created using the temperature measurement results of the pre-heating stage for solving an inverse problem, and determining the formation permeability profile from the created model.

Abstract: A technique includes completing a well, including installing a tubing string that includes a screen in the well and installing a fiber-based material outside of the screen. The technique further includes using the well as an injection well, including communicating a fluid into the tubing string to cause an injection flow to be communicated in a fluid flow path from an interior of the tubing string, through the screen and into a formation.

Abstract: A method and systems for using a non-volatile solvent to recover heavy oils are provided. In a method a solvent that includes a non-volatile component is injected into the reservoir. A mobilizing fluid is injected into the reservoir. Fluid is produced from the reservoir, wherein the fluid comprises the solvent, the mobilizing fluid, and the hydrocarbons from the reservoir.

Abstract: A method of producing from a subterranean formation can include injecting steam into the formation, and then automatically opening at least one valve in response to the steam condensing. A well system can include a tubular string disposed in a wellbore, the tubular string including at least one valve, steam which flows from the wellbore into a formation surrounding the wellbore, and alternately flows from the formation into the wellbore as liquid water, and the valve opening automatically in response to presence of the liquid water in the wellbore.

Abstract: Processes for recovering hydrocarbons from subterranean formations are disclosed. The hydrocarbon can be contacted with water or steam and one or more additives, and subsequently recovered. The hydrocarbon can be selected from the group consisting of heavy or light crude oil, bitumen, an oil sand ore, a tar sand ore and combinations thereof. The additive can be, for example, a fluorinated hydrocarbon, one or more alcohols, combinations of alcohols, and combinations of one or more alcohols and one or more fluorinated hydrocarbons. Compositions or mixtures including hydrocarbons, water or steam, and additives are also disclosed.

Abstract: Methods of extracting a hydrocarbon-based product from subsurface (oil) shale formations are provided. These methods rely on the use of an extraction fluid comprising pentane for facilitating the production of a mobile hydrocarbon-based product when the pentane contacts hydrocarbons in subsurface shale. The contacting process, and the subsequent process of recovering the mobile hydrocarbon-based product, is further enhanced by the methods of fracturing and/or rubblizing portions of the shale formation, so as to enhance their fluid permeability.

Abstract: Methods for recovery of heavy oils use selective catalytic downhole upgrading with SAGD technology. Certain embodiments include extracting heavy oil using a SAGD process and upgrading the heavy oil in a production well with a cracking catalyst. The cracking catalyst is introduced into the production well, allowing the extracted hydrocarbons to interface with the cracking catalyst to upgrade the hydrocarbons. The upgraded hydrocarbons are then separated from the cracking catalyst. This upgraded stream has a lower molecular weight, significantly reducing the viscosity of the produced hydrocarbons. A gasifier is provided to gasify a portion of the slurry containing unconverted heavy oil and cracking catalyst to produce syngas. The syngas may then be used to produce steam for use in the SAGD extraction process, improving energy efficiency of the process. Further, formation catalyst losses are avoided as the catalyst injected into the well is recovered and available for reuse.

Abstract: A downhole apparatus for oil sand exploitation, including at least a casing for housing a water conduit for receiving water, at least one steam generation chamber being in fluid communication with said water conduit and having at least one steam outlet, at least one electrical heater, being thermally connected to said steam generation chamber, at least one crude oil conduit for recovering crude oil. A method including injecting steam from at least one steam generation chamber coupled to an oil recovery conduit into a reserve; and removing oil from the reserve through the conduit, wherein the least one steam generation chamber is disposed on the oil recovery conduit, and the steam generation chamber includes a plurality of heating conduits each including a heating element and a thermally conductive material therein, and at least one reservoir surrounding the plurality of heating conduits from which the steam is produced.

Abstract: Methods relate to a steam-gas-solvent (SGS) process for recovery of heavy crude oil and bitumen. The methods include injecting a steam-gas-solvent mixture to mobilize hydrocarbons in a formation and producing from the formation the hydrocarbons that are mobilized. The steam-gas-solvent mixture includes steam, a gas non-condensable under reservoir operating conditions and a solvent condensable under reservoir operating conditions.

Abstract: A method for generating steam from a feedwater inlet stream including impurities is disclosed. The method involves receiving the feedwater inlet stream at an inlet of a steam generator and causing the feedwater stream to flow through a tubing circuit to an outlet of the tubing circuit, the tubing circuit having a substantially un-rifled bore defined by a metal wall. The method also involves delivering a heat flux to the feedwater stream through the metal wall of the tubing circuit to generate steam by causing evaporation of feedwater within the tubing circuit, and controlling at least one of a flow rate of the feedwater stream and the heat flux to cause generation of an outlet stream at the outlet includes a steam portion and liquid phase portion, the steam portion being greater than about 80% of the outlet stream by mass. The steam portion provides sufficient cooling of the metal wall to maintain a wall temperature at less than a threshold temperature.

Abstract: Embodiments presented herein provide an evaporation based zero liquid discharge method for generation of up to 100% quality high pressure steam from produced water in the heavy oil production industry. De-oiled water is processed in an evaporation system producing a distillate that allows steam to be generated with either drum-type boilers operating at higher pressures or once-through steam generators (OTSGs) operating at higher vaporization rates. Evaporator blowdown is treated in a forced-circulation evaporator to provide a zero liquid discharge system that could recycle >98% of the deoiled water for industrial use. Exemplary embodiments of the invention provide at least one “straight sump” evaporator and at least one hybrid external mist eliminator. Embodiments of the evaporation method operate at a higher overall efficiency than those of the prior art by producing distillate at a higher enthalpy which minimizes the high pressure boiler preheating requirement.

Abstract: A system comprising a well drilled into an underground formation comprising hydrocarbons; a water supply; a steam production facility, the steam production facility comprising a filter to remove at least 80% of a quantity of divalent cations in the water supply; an exchange resin to remove at least 80% of a quantity of divalent cations in a filtered water stream that has already passed through the filter; a steam injection facility connected to the well and the steam production facility, adapted to inject the steam into the well.

Abstract: A method includes performing a chemical process to create a chemical product and an amount of heat, and transferring the heat to a first fluid. The method further includes hydrating a polymer in the first fluid, and adding the chemical product from the chemical process to the first fluid to create a treatment fluid. The method further includes diluting the treatment fluid with respect to at least one constituent of the treatment fluid. The method includes treating a formation of interest in a wellbore with the treatment fluid. The method includes changing a formulation of the treatment fluid during the treating. The method also includes extending the treating beyond a design amount, or ending the treatment before the design amount and preserving some reagents of the chemical process.

Abstract: A process for purifying extracted oil, byproducts, and wastewater, including the steps of: providing a composition having at least one solvent, an alkaline agent, a deflocculant, at least one surfactant selected from the group comprising an alkoxylated alcohol surfactant, an alkylamino-polyethoxy-sulfate surfactant, a polyether-phosphate ester surfactant, a surfactant that is a phosphate ester of an ethoxylated alcohol, and a surfactant that is a polyethyleneglycol monoaklyl ether, and a bonding agent; and associating the composition with at least one of extracted oil, byproducts, and wastewater—including, but not limited to, froth, middlings, tailings, mature fine tailings, solids, and combinations thereof.

Abstract: The present invention provides a system and method for producing oil in which an ether-containing formulation is injected into a formation containing oil and an oil-immiscible formulation is injected into the formation, and oil is produced from the formation. The oil-immiscible formulation has a salt content of at most 5 wt. % and is comprised of water having a salt content of at most 5 wt. %.

Abstract: A method for treating a nahcolite containing subsurface formation includes removing water from a saline zone in or near the formation. The removed water is heated using a steam and electricity cogeneration facility. The heated water is provided to the nahcolite containing formation. A fluid is produced from the nahcolite containing formation. The fluid includes at least some dissolved nahcolite. At least some of the fluid is provided to the saline zone.

Abstract: A method is disclosed for in-situ upgrading bitumen or heavy oils during thermal recovery operations. In one embodiment, steam injection for thermal recovery of bitumen in a dolomitic or limestone reservoir matrix material can be carried out at a higher temperature, a higher pressure, a longer dwell time or a combination of all three to allow the mobilized bitumen to remain in contact with the catalytic materials in the dolomitic or limestone reservoir matrix material for longer times at higher temperatures and pressures. In another embodiment, catalytic materials such as for example, oxides or carbonates of calcium, magnesium, potassium, nickel and/or iron can be injected into the reservoir along with steam to further enhance catalytic activity during the heating, mobilization and recovery phases of a thermal recovery operation.

Abstract: A downhole assembly may include a housing having an outer surface and an inner surface, the outer surface adapted for contact with a downhole fluid, the inner surface defining an interior volume. One or more heat producing components may be disposed within the interior volume and in thermal contact with a structural component (e.g., chassis). One or more thermal dissipation members may be disposed within the housing, the one or more thermal dissipation members in thermal contact with the chassis and in thermal contact with the inner surface of the housing.

Abstract: The invention relates to a method for producing steam comprising the successive steps of: providing feedwater containing carbonate and/or sulfate ions; adding a crystallizing reagent able to react with carbonate and/or sulfate ions to the feedwater, in order to produce carbonate and/or sulfate crystals; filtering the feedwater with a ceramic membrane to produce a permeate stream; supplying the permeate stream to a boiler; and generating steam in the boiler. The invention also relates to an installation adapted for implementing said method, as well as to a process for extracting hydrocarbons from a subterranean formation using the abovementioned method for producing steam.

Abstract: A method for producing bitumen or heavy oil from a subterranean reservoir comprising a carbonate mineral solid matrix comprising injection or co-injection of a gas other than carbon dioxide, injection or co-injection of a carbon containing gas containing a relatively low amount of carbon dioxide, injection of steam providing bicarbonate/alkalinity, or increasing the subterranean reservoir pressure, such that the dissolution and re-precipitation of carbonates is suppressed thereby.

Abstract: A method for accommodating thermal expansion of a heater in a formation includes flowing a heat transfer fluid through a conduit to provide heat to the formation and providing substantially constant tension to an end portion of the conduit that extends outside the formation. At least a portion of the end portion of the conduit is wound around a movable wheel used to apply tension to the conduit.

Abstract: Produced water is treated by raising the pH to a level that significantly increases silica solubility and breaks emulsions. So treated water is then de-oiled, filtered, and subjected to ion exchange chromatography to reduce water hardness prior to feeding into a steam generator to form an intermediate quality steam. If desired, the intermediate quality steam is directly used in SAGD, or separated into a high quality steam and condensate, which is further treated to obtain additional water that can then be used in the steam generator.

Abstract: A method of permeating and infusing a formation around the borehole with wax by heating a formation surrounding a borehole and pumping molten wax into the formation, wherein the molten wax flows into and fills voids the formation without disrupting the formation is described. Also, a method of permeating and infusing a formation around the borehole with wax by heating a formation surrounding a borehole, pumping molten wax into the borehole, heating and circulating the molten wax vertically within the borehole for an extended period using a heater and pump attached to a circulation pipe extended to the bottom of a zone of the borehole to be heated, and recovering molten wax from the borehole by displacing it back to the surface with another material of different density is described.

Abstract: A thermal convertor is formed from a controlled combustion chamber selectively supplied by an appropriate fuel, preferably diesel, and compressed air. The control over the temperature of the combustion chamber is provided by regulating the flow of fuel, air and pressure into and out of the combustion chamber. Flow control valves open or close the inputs of fuel and water to, and the output of the superheated vapors from, the combustion chamber to specifically control the behavior of the combustion chamber and the composition and quality of the output from the combustion chamber. This assembly is then used to inject superheated nearly oxygen-free vapors including well treatment chemicals into a well bore cleaning the well, including the annulus and rathole, near-well bore and perforations of fines and asphaltenic particles, then stimulating an existing but newly cleaned well to produce additional oil.

Abstract: Methods and apparatus relate to producing hydrocarbons. Injecting a fluid mixture of steam and carbon dioxide into a hydrocarbon bearing formation facilitates recovery of the hydrocarbons. Further, limiting amounts of non-condensable gases in the mixture may promote dissolving of the carbon dioxide into the hydrocarbons upon contact of the mixture with the hydrocarbons.

Abstract: A system for recovering products from a gas stream comprises a cooled chamber having an inlet that feeds the gas stream to a plurality of sequential conduit loops within the chamber. A critical orifice follows each loop, and each loop includes an output port. Based upon the physical characteristics of each loop, the sizing of the critical orifice following the loop, and the temperature within the chamber, different products are condensed from the gas stream through the output ports. The system may be configured to condense hydrocarbonaceous products such as ethane, propane, butane or methane, as well as fundamental products such as carbon dioxide, nitrogen or hydrogen. Gaseous products may be stored in gas or liquid form or vented to atmosphere depending upon amount, purity, and so forth.

Abstract: Apparatus and methods are described for recovering hydrocarbonaceous and additional products from nonrubilized oil shale and oil/tar sands. One or more initial condensation steps are performed to recover crude-oil products from the effluent gas, followed by one or more subsequent condensation steps to recover additional, non-crude-oil products. The effluent gas is maintained under a negative pressure from the hole and through the initial and subsequent condensation steps. This provides numerous advantages, including the adjustment of various physical parameters during the extraction process. Such adjustment allows the ratio of oils types to be varied, the ratio of hydrocarbonaceous products to non-crude products to be varied, contamination control, and other disclosed advantages.

Abstract: Apparatus and methods for recovering hydrocarbonaceous and additional products from nonrubilized oil shale and oil/tar sands. One or more initial condensation steps are performed to recover crude-oil products from the effluent gas, followed by one or more subsequent condensation steps to recover additional, non-crude-oil products. At least a portion of the exhaust gas from a combustor may be routed through a heat exchanger to produce the processing gas, the composition of which may be adjusted so that it contains approximately 1% oxygen or less. The subsequent condensation steps may be carried out in at least one cooled chamber having a sequence of critical orifices maintained at a negative pressure. Carbon sequestration steps may be performed wherein recovered carbon dioxide is delivered down the hole following the recovery of the hydrocarbonaceous products. Various physical parameters may be adjusted to vary the recovery of crude oil or other products or contaminants from the effluent gas.

Abstract: The invention relates to methods and apparatuses for the subterranean injection of reactive substances like propellants into wellbores and subterranean reservoirs. These methods and apparatuses controls the temperature of a reactive substance for safe handling at surface and controls the decomposition rate of the substances in the subterranean environment. In addition, these methods and apparatuses provide a means for safe dilution of reactive fluids in the event of a leak or spillage of the reactive substance.

Abstract: A method of inducing fracture in at least a portion of a geologic structure includes inducing acoustic waves into a fluid medium present in a borehole extending at least partially into the structure. Embodiments may include preheating or pressurizing the fluid medium prior to inducing the acoustic wave therein.

Abstract: The present invention relates to a method and system for producing hydrocarbons from a hydrocarbon containing hydrate reservoir. The method includes providing at least one producer well in fluid communication with a producing facility and with a hydrocarbon containing hydrate reservoir. The hydrate reservoir is in fluid communication with a head space disposed above the hydrate formation. The head space contains disassociated hydrocarbons and water. A sweep gas is swept through the head space to remove the disassociated gas and water from the hydrate reservoir and to transport the disassociated gas and water to the at least one producer well. The additional pressure and/or heat provided by the sweep gas may help inhibit the reformation of disassociated gas and water into hydrates allowing for enhanced production rates. The additional heat will also help increase the disassociation rate of the upper part of the hydrate formation adjacent to the head space.

Abstract: A method of producing hydrocarbon fluids with improved hydrocarbon compound properties from a subsurface organic-rich rock formation, such as an oil shale formation, is provided. The method may include the step of heating the organic-rich rock formation in situ. In accordance with the method, the heating of the organic-rich rock formation may pyrolyze at least a portion of the formation hydrocarbons, for example kerogen, to create hydrocarbon fluids. Thereafter, the hydrocarbon fluids may be produced from the formation. Hydrocarbon fluids with improved hydrocarbon compound properties are also provided.

Abstract: A method of servicing a wellbore, comprising providing a fluid diode in fluid communication with the wellbore, and transferring a fluid through the fluid diode. A fluid flow control tool, comprising a tubular diode sleeve comprising a diode aperture, a tubular inner ported sleeve received concentrically within the diode sleeve, the inner ported sleeve comprising an inner port in fluid communication with the diode aperture, and a tubular outer ported sleeved within which the diode sleeve is received concentrically, the outer ported sleeve comprising an outer port in fluid communication with the diode aperture, wherein a shape of the diode aperture, a location of the inner port relative to the diode aperture, and a location of the outer port relative to the diode aperture provide a fluid flow resistance to fluid transferred to the inner port from the outer port and a different fluid flow resistance to fluid transferred to the outer port from the inner port.

Abstract: A method of in-situ processing of a subterranean oil shale formation to produce hydrocarbons comprising contacting the oil shale with (i) a carbon monoxide/water mixture or (ii) a carbon monoxide/water/hydrogen mixture together with at least one liquefaction promoter, under pressure and heat to produce hydrocarbons.