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Publication numberUS3342258 A
Publication typeGrant
Publication dateSep 19, 1967
Filing dateMar 6, 1964
Priority dateMar 6, 1964
Publication numberUS 3342258 A, US 3342258A, US-A-3342258, US3342258 A, US3342258A
InventorsMichael Prats
Original AssigneeShell Oil Co
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Underground oil recovery from solid oil-bearing deposits
US 3342258 A
Abstract  available in
Images(1)
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Claims  available in
Description  (OCR text may contain errors)

M. PRATS Sept. 19, 1967 BEARING DQEPOSITS UNDERGROUND OIL RECOVERY FROM SOLID OIL- Filed March 6, ,1964

Fl G. 2

FIG.

INVENTOR:

M. ,PRATS BY= H1 HIS A'GENT United States Patent 3,342,258 UNDERGROUND OIL RECOVERY FROM SOLID OIL-BEARING DEPOSITS Michael Prats, Houston, Tex., assignor to Shell Oil Company, New York, N.Y., a corporation of Delaware Filed Mar. 6, 1964, Ser. No. 349,923 4 Claims. (Cl. 166-11) This invention relates to the art of recovering oil from underground formations, and pertains more particularly to oil recovery methods which utilize combustion within the reservoir to aid in the displacement and recovery of the oil. In one of its more specific embodiments, the invention is directed to the recovery of oil from solid oilbearing deposits, such as the Athabasca tar sands and the like or the large deposits of oil shale found in various sections of the United States, particularly in Colorado and surrounding States.

Various techniques have been tried in an attempt to recover oil, particularly from bituminous or solid oilbearing deposits and tar sands. However, many of them have been found to be unsuccessful for one or more reasons. Thus, one of the more often-attempted methods includes fracturing a bituminous formation to open passages therein between at least two wells, introducing a propping agent in the open passages or fractures in an attempt to maintain them permeable when the pressure on the formation has been decreased so that the fractures close, and then trying to initiate and maintain combustion so as to volatilize at least a portion of the oil and attempt to displace it to a production well or wells in order to effect the recovery of the oil therefrom.

There are certain defects and disadvantages which are inherent when the above-outlined technique is used for recovery of oil, for example, from tar sands and the like. Fractures are formed by increasing the pressure on a fluid confined within a section of a borehole. The direction along which the fracture is most extensive is determined by the tectonics and cannot to any significant extent be controlled by personnel conducting the fracturing operation. The fracture may be vertical and extensive along only, for example, a north-south direction. On the other hand, it may be horizontal and radial but have a significant thickness and extent only in one direction.

Field experience has demonstrated that in transporting a granular or propping agent such as sand into a fracture, the propping agent may move away from the injection well along a meandering path. For example, in fracturing a well surrounded by concentric rings of wells, the propping agent may be transported to both the near and far wells north of the injection well, to the far but not the near wells west of the injection well, and may never be transported to any of the wells south or east of the injection well.

Thus, it may be seen that there are certain inherent disadvantages in fracturing a formation and propping the fracture with, for example, sand to improve the overall permeability between a pair of wells. Sand can be strained out of the fracturing fluid entering a thin portion of a fracture. A horizontal and radially-extensive fracture may be thick enough to accommodate the passage of sand grains in some sectors but not in others. For example, when the sand-transporting fluid is injected, the sand grains may move into only a northeast sector since in other directions the fracture is too thin to permit the passage of sand grains. In such a case, when the fracturing pressure is reduced and the formation is allowed to subside, a permeable streak will have been established only in the northeast sector.

Additionally, sand can be dropped out of a fracturing fluid moving at a low velocity. A horizontal and radially- Patented Sept. 19, 1967 extensive fracture having a uniform thickness adequate for the passage of said grains may receive the sand or propping agent only near the well. As the sand-transporting fluid is pumped into such a fracture at a given rate, the volume of the space into which the fluid is moving increases with distance away from the well, and the velocity at which the fluid is moving is correspondingly decreased. When the velocity of a sand-transporting fluid reaches the minimum value unique to the particular fluid, a sand out occurs as the fluid deposits the grains it was transporting. Therefore, the injection of a sand-transporting fluid into such a fracture may result in the establisment of a permeable streak in the immediate vicinity of the injection Well.

In oil fields wherein the oil-bearing formation contains viscous petroleum materials, the forming and propping of a fracture with sand is, in practice, ineflective as a means of improving fluid communication between wells. Unless such a fracture can be preheated and maintained hot, it is promptly plugged by the intrusion of the viscous petroleum material. It is to be further noted that hydraulicallyinduced fractures have thicknesses only in the order of A; to A of an inch. Even where fractures can be propped with sand grains to maintain most of this thickness after fracturing pressure has been reduced, the sand-filled fractures only amount to very thin streaks of high permeability.

It is therefore an object of the present invention to avoid the above and other defects and disadvantages and to provide an economical and eflicient method for recovery of hydrocarbones from oil-bearing under round formations, and particularly from bituminous deposits.

A further object of the present invention is to provide a recovery method wherein the permeability between pairs of wells can be established or substantially increased without the need for fracturing the oil-bearing formation and propping the fractures with sand particles.

Another object of the present invention is to provide a method for recovering oil from underground oil-bearing formations which process utilizes in situ combustion, which makes use of a zone of increased permeability established between pairs of wells.

These and other objects of this invention will be understood from the following description taken with reference to the drawing, wherein:

FIGURE 1 is a diagrammatic view taken in longitudinal section of three wells in which a fracturing operation is being carried out in order to establish communication through an oil-bearing formation between the wells; and,

FIGURE 2 is a diagrammatic view taken in partial longitudinal section illustrating the three wells of FIG- URE 1 at a time when the fracturing pressure has been reduced and after a permeable zone has been established between the Wells.

The oil recovery method of the present invention contemplates the use of at least a pair of wells extending down into communication with an oil-bearing formation and preferably additional Wells whereby in situ combustion or a fluid drive may be carried out. With the formation to be treated being provided with at least a pair of wells, the oil-bearing formation is then hydraulically fractured, preferably with horizontal fractures extending the entire way between the wells and at a proper vertical level or levels within the fomation and subsequently an oilremoval or entraining fluid is conveyed through the fracture or fractures thus formed to extract oil from the fractures as well as the portions of the formation adjacent thereto to form a permeable flow area between the wells. After a permeable flow area has been formed in this manner, combustion is initiated along the resultant and more permeable zone of the oil-bearing formation and oil is produced by advancing the combustion zone toward one or more producing wells.

Referring to FIGURE 1 of the drawing, three wells are shown as having been drilled down into the oil-bearing zone and aligned with casings 10, 11 and 12. The casings 10, 11 and 12 are preferably closed at the top, depending upon the operation being carried out, with smaller-diameter pipes 13, 14 and 15 extending through the closed upper ends of the casings 10, 11 and 12. The smaller-diameter pipes 13, 14 and 15 may be used for various operations, depending on how they are equipped or what they are connected to. Thus, in the operation shown in FIGURE 1 at least one of the pipes, say pipe 13, would be connected to a source of pressure fluid whereby the oil-bearing formation 16 could be fractured, as at 17, with the fracture extending between at least two of the wells. The portions of the well casings 11 and 12 Within the oil-bearing formation 16 are provided with series of perforations 18 whereby the interior of each of the well casings is brought into communication with the oil-bearing zone whereby fluids can be either forced into the zone 16 or extracted therefrom.

The wells in the oil field may be newly drilled wells or may have been wells from which production fluid is no longer obtained. If the wells had not been previously drilled and it is necessary to drill new wells, the wells are preferably placed in a standard, staggered, spaced pattern with relatively close spacing between them.

After the wells have been established in a suitable position, the oil-bearing formation is fractured, preferably in a generally horizontal plane whereby the hydraulicallyformed fractures extend all the way between wells at the proper vertical levels within the formation. It is to be understood that at some levels vertical fractures will be formed instead and these vertical fractures can also be utilized by the method of the present invention. Generally, it is preferable to have the fractures disposed near the bottom of the oil-bearing formation. However, the fractures may be located elsewhere, and it is also desirable at times to fracture the oil-bearing formation or stratum at one or more levels so as to facilitate the in situ combustion in the oil-bearing formation as well as the recovery of oil therefrom.

The fractures 17 may be held open by fluid under pressure, said fracture fluid being preferably an oil-removing or entraining fluid which is passed from one well to another to leach out the oil in the fractures and in portions of the formation forming the walls of the fracture. Any of the well-known oil-entraining or removal fluids may be used for this purpose. Thus, it is possible to employ normally gaseous hydrocarbon fractions, such as methane, ethane, propane, butane and pentane hydrocarbons and mixtures thereof, which latter may be used in a liquid, gaseous or mixed phase state. Also, instead of using the hydrocarbon fractions, which are miscible with the oil to be entrained and recovered from the fractures and the formations immediately adjacent thereto, it is also possible to use non-miscible entraining or removal fluids. Such non-miscible entraining fluids may be aqueous solutions containing a surfactant, e.g., an alkali metal soap or a non-ionic surfactant. These surfactants may be added as such to the water introduced into the formation to entrain or leach the oil therefrom, or, as an alternative, the surfactant may be formed in situ, e.g., by first introducing one reagent such as an acid-action material (such as a fatty acid), into the formation, and following it with an aqueous solution containing a second reagent, e.g., a basic-acting compound, such as sodium hydroxide so that the reagents interact in the fractures and surrounding formations to form a surfactant which aids entraining or leaching the oil, and aiding in its recovery. As stated, such a treatment opens up a formation and helps in the subsequent step of recovering the oil from the formation thus treated.

After the establishment of the horizontal passageways and having the walls of the passageways leached so as to remove a substantial amount of the oil originally present therein, it will be found that a zone of increased permeability has been formed between the wells which exists after the fracture has been allowed to close by the reduction of the pressure of the injected fluid. Use is subsequently made of this permeable zone between the wells to carry out any standard pattern for recovering oil from the oil-bearing formation, such, for example, by in situ combustion.

It is a uniquely advantageous feature of this invention that by selecting the locations and rates at which the oilremoval fluids are pumped into and out of the oilbearing formation, the zones of increased permeability can be shaped into the patterns best suited for the subsequent production by in situ combustion. For example, from wells arranged in rows the entraining fluids can be forced to flow along continuous paths directly across the space between the rows to provide a substantially uniform permeable zone extending like a blanket beneath a series of rows of wells to be utilized in a line drive underground combustion oil production process. When a zone of adequate permeability has been provided between a 'pair of wells, it is preferable but not essential to reduce the pumping pressures and allow the formation to sink down onto the channel of cleaned formation, that is, the zone of increased permeability 2% (FIGURE 2). In addition to reducing the operating costs during the in situ combustion production phase, this lowering of the pumping pressure tends to limit the extensions of the channel of clean sand and prevent the channel from being extended beyond a desired production well. A zone of adequate permeability is established when a combustion-supporting gas well flows between a pair of wells at a rate required to support underground combustion in response to a pressure less than the overburden pressure. In general a flow of at least several hundred thousand cubic feet per day is desirable to support the combustion.

The initiation of combustion along the resulting permeable zone 20 of the oil bearing formation 16 is accomplished by pumping a combustion-supporting gas through the channel of clean sand and heating oil that is contacted by the gas to a temperature at which the oil is ignited. This can be facilitated by use of down-hole heaters and any suitable chemical and/ or mechanical means for increasing the speed or ease of igniting the oil in a subsurface formation. When down-hole heaters are used, the combustion-supporting gases can comprise air which is heated as it passes the heater. When steam is used in cleaning the formation in the previous step, it is particularly advantageous to use steam as a heat-imparting gas to assist in the ignition. During the combustion drive step, the pumping pressures are preferably, but not necessarily, held below the overburden pressure. In carrying out an underground combustion in the present method, the ignition occurs along the edges of the channel of clean sand in the vicinity of the injection well. As the oil is heated to a temperature at which it begins to flow, the oil moves into and along the channel of increased permeability under the impetus of the gas stream. In general, the gas tends to move away from the injection well in all directions and then is guided, confined and accelerated by the walls of the permeable channel.

A reverse drive combustion process, in which the oil is ignited near the production well and the combustion front is propagated against the flow of gas toward the injection well, comprises a preferred type of underground combustion process for use in the present invention. In this type of process the injected combustion-supporting gas is guided by the impermeable formation bounding the permeable channel and conveyed to the continuously expanding zone in which the heat is most efliciently utilized. In the hot zone, downstream from the combustion point the oil in the formation is concurrently heated and displaced to leave a zone that tinually expanding.

Thus, it has been seen that by the present invention a method has been provided for forming a permeable flow Zone between a pair of wells by leaching of the oil from the formation rather than using sand as a propping agent. Leaching avoids the problem of having sand straining out or depositing in a thin portion of a fracture thereby reducing the distance or limiting the direction along which a permeable streak is established. The leaching fluid creates permeability by dissolving plugging materials. Thus, permeability in a formation can be created wherever a leaching fluid can be caused to flow. The leaching fluid can be forced to flow in one or a plurality of directions between a pair or a series of wells which are to be used in an underground combustion operation by employing a pressure sufiicient to hydraulically support a fracture until the leaching action has established an adequate degree of permeability through the leached-out walls of the fracture.

Leaching also avoids the problem of having a sand out limit the distance over which a streak of permeability is established. The leaching fluid can be forced to flow along and dissolving plugging materials along the full extent of the distance between the wells which are to be used in a fluid drive operation. Where a viscous petroleum material tends to plug permeable zones, the leaching can be done with steam which heats while it extracts. In the later stages of leaching and heating a zone with steam, air can be mixed with the steam and the mixture can be used to ignite the petroleum present along the edges of the permeable zone while that zone is maintained hot. In leaching operations, the thickness of the permeable zone can be extended for a significant distance into the wall of the fracture. The leaching fluid removes the petroleum exposed to the fracture and then moves into the regions previously plugged by the presence of petroleum to progressively increase the thickness of the permeable zone.

From the above description it may be seen that the key aspects of the present invention involve the following steps. (1) Opening a pair of wells into an oil-bearing reservoir formation that is impermeable at the reservoir conditions but is permeable when the oil is heated or extracted. (2) Pumping liquid between the wells at pressures and rates adjusted to fracture the formation and maintain a separation between layers of the formation along a flow path extending between the wells in a selected pattern that is established by the locations and rates at which the liquid is pumped into and out of the reservoir formation. (3) Pumping an oil-entraining liquid along the same flow path and extracting oil from the adjacent formation layers until portions of the layers become permeable and a combustion-supporting gas will flow between the wells, at a rate supporting an underground combustion, in response to a pressure less than the overburden pressure. (4) Pumping a combustion-supporting gas between the wells, igniting oil that is contacted by the gas, and producing oil that is heated by the combustion.

This combination of steps makes it possible to shape the permeable channel in the manner best suited for the type of underground combustion process that is to be used. It also uses the formation characteristic of being impermeable when cold and permeable when hot to provide an expendible channel for guiding the injected air to the point at which it is reacted. For example, in a reverse combustion, substantially all of the air is confined within the permeable zone and conveyed to the combustion zone near the producing well. As the combustion heats the adjacent formation, the oil is displaced by hot combustion products and that portion of the formation is rendered permeable. Thus, the channel that conveys the combustion-supporting gas to the point at Which it is reacted is destroyed as the hot zone expands and creates a permeable is hot, permeable and conformation through which a discrete channel of permeability is no longer needed.

In the present process the normal impermeability of the formation is used (1) as part of the system for conveying the combustion-supporting gas to the combustion front and (2) as a means for shaping the permeable zone through which the leading edge of the combustion front will propagate to a shape best suited for the type of underground combustion drive that is to be performed.

I claim as my invention: 1. A method of recovering oil from an underground oil-bearing formation selected from the group consisting of tar sand and oil shale which is penetrated by a plurality of wells, at least one of said wells being normally a fluid injection well and at least one well adjacent said injection well being normally an oil-production well, said method comprising establishing communication between all of said wells and the oil-bearing formation surrounding said wells,

fracturing the formation between a fluid-injection well and at least one adjacent oil-production well in a manner such that the wells are in fluid flow communication with each other through said oil-bearing formation, injecting an oil-removal fluid down the injection well and through the fracture to said production well at a pressure sulficient to maintain the fracture open,

maintaining said injection of oil-removal fluid through said fracture for a time suflicient to remove oil from the walls of the formation forming the fracture and increase the permeability of said walls to a value sufiicient to permit the flow of oil therethrough when said fracture is closed,

stopping the injection of said oil-removal fluid and reducing the fluid injection pressure whereby said fracture closes with a permeable zone formed along said closed fracture line,

injecting a combustible driving oil-displacement fluid in said injection well and through said oil-bearing formation to said production well at a pressure less than that which would cause the formation between said wells to fracture, and

recovering oil therefrom through said oil-production well.

2. The method of claim 1 wherein said oil-bearing formation includes at least one layer of a permeable matrix which extends between the wells and is plugged by oil and wherein said fracturing operation is carried out at the level of said permeable matrix to fracture said matrix.

3. The method of claim 1 wherein the driving fluid is obtained by initiating combustion in said formation between said wells to drive oil to a production well.

4. The method of claim 3 wherein said combustion is accomplished by pumping combustion supporting gases down said injection well and through the previouslyformed permeable zone between the wells until oil along the edges of said zone is ignited.

References Cited UNITED STATES PATENTS CHARLES E. OCONNELL, Primary Examiner.

JACOB L. NACKENOFF, STEPHEN J. NOVOSAD,

Examiners.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US2813583 *Dec 6, 1954Nov 19, 1957Phillips Petroleum CoProcess for recovery of petroleum from sands and shale
US2969226 *Jan 19, 1959Jan 24, 1961Pyrochem CorpPendant parting petro pyrolysis process
US3004594 *Nov 19, 1956Oct 17, 1961Phillips Petroleum CoProcess for producing oil
US3086760 *May 25, 1960Apr 23, 1963Fmc CorpMethod of creating an underground communication
US3091292 *Feb 12, 1959May 28, 1963Texaco IncRecovering hydrocarbons from subsurface formations
US3149670 *Mar 27, 1962Sep 22, 1964Smclair Res IncIn-situ heating process
US3167121 *Dec 13, 1962Jan 26, 1965Socony Mobil Oil Co IncMethod for producing high viscosity oil
US3273640 *Dec 13, 1963Sep 20, 1966Pyrochem CorpPressure pulsing perpendicular permeability process for winning stabilized primary volatiles from oil shale in situ
US3285335 *Dec 11, 1963Nov 15, 1966Exxon Research Engineering CoIn situ pyrolysis of oil shale formations
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3382922 *Aug 31, 1966May 14, 1968Phillips Petroleum CoProduction of oil shale by in situ pyrolysis
US3396791 *Sep 9, 1966Aug 13, 1968Shell Oil CoSteam drive for incompetent tar sands
US3399722 *May 24, 1967Sep 3, 1968Pan American Petroleum CorpRecovery of petroleum by a cyclic thermal method
US3400762 *Jul 8, 1966Sep 10, 1968Phillips Petroleum CoIn situ thermal recovery of oil from an oil shale
US3456731 *May 18, 1967Jul 22, 1969Phillips Petroleum CoIn-situ production of oil from strata of low permeability
US4265310 *Oct 3, 1978May 5, 1981Continental Oil CompanyFracture preheat oil recovery process
US4687058 *May 22, 1986Aug 18, 1987Conoco Inc.Solvent enhanced fracture-assisted steamflood process
US6994168Apr 24, 2001Feb 7, 2006Scott Lee WellingtonIn situ thermal processing of a hydrocarbon containing formation with a selected hydrogen to carbon ratio
US6997518 *Apr 24, 2002Feb 14, 2006Shell Oil CompanyIn situ thermal processing and solution mining of an oil shale formation
US7040397Apr 24, 2002May 9, 2006Shell Oil CompanyThermal processing of an oil shale formation to increase permeability of the formation
US7644765Oct 19, 2007Jan 12, 2010Shell Oil CompanyHeating tar sands formations while controlling pressure
US7673681Oct 19, 2007Mar 9, 2010Shell Oil CompanyTreating tar sands formations with karsted zones
US7673786Apr 20, 2007Mar 9, 2010Shell Oil CompanyWelding shield for coupling heaters
US7677310Oct 19, 2007Mar 16, 2010Shell Oil CompanyCreating and maintaining a gas cap in tar sands formations
US7677314Oct 19, 2007Mar 16, 2010Shell Oil CompanyMethod of condensing vaporized water in situ to treat tar sands formations
US7681647Oct 19, 2007Mar 23, 2010Shell Oil CompanyMethod of producing drive fluid in situ in tar sands formations
US7683296Apr 20, 2007Mar 23, 2010Shell Oil CompanyAdjusting alloy compositions for selected properties in temperature limited heaters
US7703513Oct 19, 2007Apr 27, 2010Shell Oil CompanyWax barrier for use with in situ processes for treating formations
US7717171Oct 19, 2007May 18, 2010Shell Oil CompanyMoving hydrocarbons through portions of tar sands formations with a fluid
US7730945Oct 19, 2007Jun 8, 2010Shell Oil CompanyUsing geothermal energy to heat a portion of a formation for an in situ heat treatment process
US7730946Oct 19, 2007Jun 8, 2010Shell Oil CompanyTreating tar sands formations with dolomite
US7730947Oct 19, 2007Jun 8, 2010Shell Oil CompanyCreating fluid injectivity in tar sands formations
US7735935Jun 1, 2007Jun 15, 2010Shell Oil CompanyIn situ thermal processing of an oil shale formation containing carbonate minerals
US7785427Apr 20, 2007Aug 31, 2010Shell Oil CompanyHigh strength alloys
US7798220Apr 18, 2008Sep 21, 2010Shell Oil CompanyIn situ heat treatment of a tar sands formation after drive process treatment
US7798221May 31, 2007Sep 21, 2010Shell Oil CompanyIn situ recovery from a hydrocarbon containing formation
US7831134Apr 21, 2006Nov 9, 2010Shell Oil CompanyGrouped exposed metal heaters
US7832484Apr 18, 2008Nov 16, 2010Shell Oil CompanyMolten salt as a heat transfer fluid for heating a subsurface formation
US7841401Oct 19, 2007Nov 30, 2010Shell Oil CompanyGas injection to inhibit migration during an in situ heat treatment process
US7841408Apr 18, 2008Nov 30, 2010Shell Oil CompanyIn situ heat treatment from multiple layers of a tar sands formation
US7841425Apr 18, 2008Nov 30, 2010Shell Oil CompanyDrilling subsurface wellbores with cutting structures
US7845411Oct 19, 2007Dec 7, 2010Shell Oil CompanyIn situ heat treatment process utilizing a closed loop heating system
US7849922Apr 18, 2008Dec 14, 2010Shell Oil CompanyIn situ recovery from residually heated sections in a hydrocarbon containing formation
US7860377Apr 21, 2006Dec 28, 2010Shell Oil CompanySubsurface connection methods for subsurface heaters
US7866385Apr 20, 2007Jan 11, 2011Shell Oil CompanyPower systems utilizing the heat of produced formation fluid
US7866386Oct 13, 2008Jan 11, 2011Shell Oil CompanyIn situ oxidation of subsurface formations
US7866388Oct 13, 2008Jan 11, 2011Shell Oil CompanyHigh temperature methods for forming oxidizer fuel
US7912358Apr 20, 2007Mar 22, 2011Shell Oil CompanyAlternate energy source usage for in situ heat treatment processes
US7931086Apr 18, 2008Apr 26, 2011Shell Oil CompanyHeating systems for heating subsurface formations
US7942197Apr 21, 2006May 17, 2011Shell Oil CompanyMethods and systems for producing fluid from an in situ conversion process
US7942203Jan 4, 2010May 17, 2011Shell Oil CompanyThermal processes for subsurface formations
US7950453Apr 18, 2008May 31, 2011Shell Oil CompanyDownhole burner systems and methods for heating subsurface formations
US7986869Apr 21, 2006Jul 26, 2011Shell Oil CompanyVarying properties along lengths of temperature limited heaters
US8011451Oct 13, 2008Sep 6, 2011Shell Oil CompanyRanging methods for developing wellbores in subsurface formations
US8027571Apr 21, 2006Sep 27, 2011Shell Oil CompanyIn situ conversion process systems utilizing wellbores in at least two regions of a formation
US8042610Apr 18, 2008Oct 25, 2011Shell Oil CompanyParallel heater system for subsurface formations
US8070840Apr 21, 2006Dec 6, 2011Shell Oil CompanyTreatment of gas from an in situ conversion process
US8083813Apr 20, 2007Dec 27, 2011Shell Oil CompanyMethods of producing transportation fuel
US8113272Oct 13, 2008Feb 14, 2012Shell Oil CompanyThree-phase heaters with common overburden sections for heating subsurface formations
US8146661Oct 13, 2008Apr 3, 2012Shell Oil CompanyCryogenic treatment of gas
US8146669Oct 13, 2008Apr 3, 2012Shell Oil CompanyMulti-step heater deployment in a subsurface formation
US8151880Dec 9, 2010Apr 10, 2012Shell Oil CompanyMethods of making transportation fuel
US8151907Apr 10, 2009Apr 10, 2012Shell Oil CompanyDual motor systems and non-rotating sensors for use in developing wellbores in subsurface formations
US8162059Oct 13, 2008Apr 24, 2012Shell Oil CompanyInduction heaters used to heat subsurface formations
US8162405Apr 10, 2009Apr 24, 2012Shell Oil CompanyUsing tunnels for treating subsurface hydrocarbon containing formations
US8172335Apr 10, 2009May 8, 2012Shell Oil CompanyElectrical current flow between tunnels for use in heating subsurface hydrocarbon containing formations
US8177305Apr 10, 2009May 15, 2012Shell Oil CompanyHeater connections in mines and tunnels for use in treating subsurface hydrocarbon containing formations
US8191630Apr 28, 2010Jun 5, 2012Shell Oil CompanyCreating fluid injectivity in tar sands formations
US8192682Apr 26, 2010Jun 5, 2012Shell Oil CompanyHigh strength alloys
US8196658Oct 13, 2008Jun 12, 2012Shell Oil CompanyIrregular spacing of heat sources for treating hydrocarbon containing formations
US8200072Oct 24, 2003Jun 12, 2012Shell Oil CompanyTemperature limited heaters for heating subsurface formations or wellbores
US8220539Oct 9, 2009Jul 17, 2012Shell Oil CompanyControlling hydrogen pressure in self-regulating nuclear reactors used to treat a subsurface formation
US8224163Oct 24, 2003Jul 17, 2012Shell Oil CompanyVariable frequency temperature limited heaters
US8224164Oct 24, 2003Jul 17, 2012Shell Oil CompanyInsulated conductor temperature limited heaters
US8224165Apr 21, 2006Jul 17, 2012Shell Oil CompanyTemperature limited heater utilizing non-ferromagnetic conductor
US8225866Jul 21, 2010Jul 24, 2012Shell Oil CompanyIn situ recovery from a hydrocarbon containing formation
US8230927May 16, 2011Jul 31, 2012Shell Oil CompanyMethods and systems for producing fluid from an in situ conversion process
US8233782Sep 29, 2010Jul 31, 2012Shell Oil CompanyGrouped exposed metal heaters
US8238730Oct 24, 2003Aug 7, 2012Shell Oil CompanyHigh voltage temperature limited heaters
US8240774Oct 13, 2008Aug 14, 2012Shell Oil CompanySolution mining and in situ treatment of nahcolite beds
US8256512Oct 9, 2009Sep 4, 2012Shell Oil CompanyMovable heaters for treating subsurface hydrocarbon containing formations
US8261832Oct 9, 2009Sep 11, 2012Shell Oil CompanyHeating subsurface formations with fluids
US8267170Oct 9, 2009Sep 18, 2012Shell Oil CompanyOffset barrier wells in subsurface formations
US8267185Oct 9, 2009Sep 18, 2012Shell Oil CompanyCirculated heated transfer fluid systems used to treat a subsurface formation
US8272455Oct 13, 2008Sep 25, 2012Shell Oil CompanyMethods for forming wellbores in heated formations
US8276661Oct 13, 2008Oct 2, 2012Shell Oil CompanyHeating subsurface formations by oxidizing fuel on a fuel carrier
US8281861Oct 9, 2009Oct 9, 2012Shell Oil CompanyCirculated heated transfer fluid heating of subsurface hydrocarbon formations
US8327681Apr 18, 2008Dec 11, 2012Shell Oil CompanyWellbore manufacturing processes for in situ heat treatment processes
US8327932Apr 9, 2010Dec 11, 2012Shell Oil CompanyRecovering energy from a subsurface formation
US8353347Oct 9, 2009Jan 15, 2013Shell Oil CompanyDeployment of insulated conductors for treating subsurface formations
US8355623Apr 22, 2005Jan 15, 2013Shell Oil CompanyTemperature limited heaters with high power factors
US8381815Apr 18, 2008Feb 26, 2013Shell Oil CompanyProduction from multiple zones of a tar sands formation
US8434555Apr 9, 2010May 7, 2013Shell Oil CompanyIrregular pattern treatment of a subsurface formation
US8448707Apr 9, 2010May 28, 2013Shell Oil CompanyNon-conducting heater casings
US8459359Apr 18, 2008Jun 11, 2013Shell Oil CompanyTreating nahcolite containing formations and saline zones
US8485252Jul 11, 2012Jul 16, 2013Shell Oil CompanyIn situ recovery from a hydrocarbon containing formation
US8536497Oct 13, 2008Sep 17, 2013Shell Oil CompanyMethods for forming long subsurface heaters
US8555971May 31, 2012Oct 15, 2013Shell Oil CompanyTreating tar sands formations with dolomite
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US8606091Oct 20, 2006Dec 10, 2013Shell Oil CompanySubsurface heaters with low sulfidation rates
US8608249Apr 26, 2010Dec 17, 2013Shell Oil CompanyIn situ thermal processing of an oil shale formation
US8627887Dec 8, 2008Jan 14, 2014Shell Oil CompanyIn situ recovery from a hydrocarbon containing formation
US8631866Apr 8, 2011Jan 21, 2014Shell Oil CompanyLeak detection in circulated fluid systems for heating subsurface formations
US8636323Nov 25, 2009Jan 28, 2014Shell Oil CompanyMines and tunnels for use in treating subsurface hydrocarbon containing formations
US8662175Apr 18, 2008Mar 4, 2014Shell Oil CompanyVarying properties of in situ heat treatment of a tar sands formation based on assessed viscosities
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US8701769Apr 8, 2011Apr 22, 2014Shell Oil CompanyMethods for treating hydrocarbon formations based on geology
US8701788Dec 22, 2011Apr 22, 2014Chevron U.S.A. Inc.Preconditioning a subsurface shale formation by removing extractible organics
US8739874Apr 8, 2011Jun 3, 2014Shell Oil CompanyMethods for heating with slots in hydrocarbon formations
US8752904Apr 10, 2009Jun 17, 2014Shell Oil CompanyHeated fluid flow in mines and tunnels used in heating subsurface hydrocarbon containing formations
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US8791396Apr 18, 2008Jul 29, 2014Shell Oil CompanyFloating insulated conductors for heating subsurface formations
US8820406Apr 8, 2011Sep 2, 2014Shell Oil CompanyElectrodes for electrical current flow heating of subsurface formations with conductive material in wellbore
US8833453Apr 8, 2011Sep 16, 2014Shell Oil CompanyElectrodes for electrical current flow heating of subsurface formations with tapered copper thickness
US8839860Dec 22, 2011Sep 23, 2014Chevron U.S.A. Inc.In-situ Kerogen conversion and product isolation
US8851170Apr 9, 2010Oct 7, 2014Shell Oil CompanyHeater assisted fluid treatment of a subsurface formation
US8851177Dec 22, 2011Oct 7, 2014Chevron U.S.A. Inc.In-situ kerogen conversion and oxidant regeneration
US8857506May 24, 2013Oct 14, 2014Shell Oil CompanyAlternate energy source usage methods for in situ heat treatment processes
US8881806Oct 9, 2009Nov 11, 2014Shell Oil CompanySystems and methods for treating a subsurface formation with electrical conductors
US8936089Dec 22, 2011Jan 20, 2015Chevron U.S.A. Inc.In-situ kerogen conversion and recovery
US8992771May 25, 2012Mar 31, 2015Chevron U.S.A. Inc.Isolating lubricating oils from subsurface shale formations
US8997869Dec 22, 2011Apr 7, 2015Chevron U.S.A. Inc.In-situ kerogen conversion and product upgrading
US9016370Apr 6, 2012Apr 28, 2015Shell Oil CompanyPartial solution mining of hydrocarbon containing layers prior to in situ heat treatment
US9022109Jan 21, 2014May 5, 2015Shell Oil CompanyLeak detection in circulated fluid systems for heating subsurface formations
US9022118Oct 9, 2009May 5, 2015Shell Oil CompanyDouble insulated heaters for treating subsurface formations
US9033033Dec 22, 2011May 19, 2015Chevron U.S.A. Inc.Electrokinetic enhanced hydrocarbon recovery from oil shale
US9033042Apr 8, 2011May 19, 2015Shell Oil CompanyForming bitumen barriers in subsurface hydrocarbon formations
US9051829Oct 9, 2009Jun 9, 2015Shell Oil CompanyPerforated electrical conductors for treating subsurface formations
US9127523Apr 8, 2011Sep 8, 2015Shell Oil CompanyBarrier methods for use in subsurface hydrocarbon formations
US9127538Apr 8, 2011Sep 8, 2015Shell Oil CompanyMethodologies for treatment of hydrocarbon formations using staged pyrolyzation
US9129728Oct 9, 2009Sep 8, 2015Shell Oil CompanySystems and methods of forming subsurface wellbores
US9133398Dec 22, 2011Sep 15, 2015Chevron U.S.A. Inc.In-situ kerogen conversion and recycling
US9181467Dec 22, 2011Nov 10, 2015Uchicago Argonne, LlcPreparation and use of nano-catalysts for in-situ reaction with kerogen
US9181780Apr 18, 2008Nov 10, 2015Shell Oil CompanyControlling and assessing pressure conditions during treatment of tar sands formations
US9309755Oct 4, 2012Apr 12, 2016Shell Oil CompanyThermal expansion accommodation for circulated fluid systems used to heat subsurface formations
US9399905May 4, 2015Jul 26, 2016Shell Oil CompanyLeak detection in circulated fluid systems for heating subsurface formations
US20020029885 *Apr 24, 2001Mar 14, 2002De Rouffignac Eric PierreIn situ thermal processing of a coal formation using a movable heating element
US20020033256 *Apr 24, 2001Mar 21, 2002Wellington Scott LeeIn situ thermal processing of a hydrocarbon containing formation with a selected hydrogen to carbon ratio
US20020033257 *Apr 24, 2001Mar 21, 2002Shahin Gordon ThomasIn situ thermal processing of hydrocarbons within a relatively impermeable formation
US20020034380 *Apr 24, 2001Mar 21, 2002Maher Kevin AlbertIn situ thermal processing of a coal formation with a selected moisture content
US20020038709 *Apr 24, 2001Apr 4, 2002Wellington Scott LeeIn situ thermal processing of a hydrocarbon containing formation using a natural distributed combustor
US20020038710 *Apr 24, 2001Apr 4, 2002Maher Kevin AlbertIn situ thermal processing of a hydrocarbon containing formation having a selected total organic carbon content
US20020038711 *Apr 24, 2001Apr 4, 2002Rouffignac Eric Pierre DeIn situ thermal processing of a hydrocarbon containing formation using heat sources positioned within open wellbores
US20020043365 *Apr 24, 2001Apr 18, 2002Berchenko Ilya EmilIn situ thermal processing of a coal formation with a selected ratio of heat sources to production wells
US20020043367 *Apr 24, 2001Apr 18, 2002Rouffignac Eric Pierre DeIn situ thermal processing of a hydrocarbon containing formation to increase a permeability of the formation
US20020046838 *Apr 24, 2001Apr 25, 2002Karanikas John MichaelIn situ thermal processing of a hydrocarbon containing formation with carbon dioxide sequestration
US20020053429 *Apr 24, 2001May 9, 2002Stegemeier George LeoIn situ thermal processing of a hydrocarbon containing formation using pressure and/or temperature control
US20020053432 *Apr 24, 2001May 9, 2002Berchenko Ilya EmilIn situ thermal processing of a hydrocarbon containing formation using repeating triangular patterns of heat sources
US20020056551 *Apr 24, 2001May 16, 2002Wellington Scott LeeIn situ thermal processing of a hydrocarbon containing formation in a reducing environment
US20020057905 *Apr 24, 2001May 16, 2002Wellington Scott LeeIn situ thermal processing of a hydrocarbon containing formation to produce oxygen containing formation fluids
US20020062051 *Apr 24, 2001May 23, 2002Wellington Scott L.In situ thermal processing of a hydrocarbon containing formation with a selected moisture content
US20020077515 *Apr 24, 2001Jun 20, 2002Wellington Scott LeeIn situ thermal processing of a hydrocarbon containing formation to produce hydrocarbons having a selected carbon number range
US20020084074 *Sep 24, 2001Jul 4, 2002De Rouffignac Eric PierreIn situ thermal processing of a hydrocarbon containing formation to increase a porosity of the formation
US20020104654 *Apr 24, 2001Aug 8, 2002Shell Oil CompanyIn situ thermal processing of a coal formation to convert a selected total organic carbon content into hydrocarbon products
US20030131994 *Apr 24, 2002Jul 17, 2003Vinegar Harold J.In situ thermal processing and solution mining of an oil shale formation
US20030164234 *Apr 24, 2001Sep 4, 2003De Rouffignac Eric PierreIn situ thermal processing of a hydrocarbon containing formation using a movable heating element
US20030213594 *Jun 12, 2003Nov 20, 2003Shell Oil CompanyIn situ thermal processing of a hydrocarbon containing formation to produce a mixture with a selected hydrogen content
US20040108111 *Apr 24, 2001Jun 10, 2004Vinegar Harold J.In situ thermal processing of a coal formation to increase a permeability/porosity of the formation
US20040177966 *Oct 24, 2003Sep 16, 2004Vinegar Harold J.Conductor-in-conduit temperature limited heaters
US20070137857 *Apr 21, 2006Jun 21, 2007Vinegar Harold JLow temperature monitoring system for subsurface barriers
Classifications
U.S. Classification166/259
International ClassificationE21B43/16, E21B43/247
Cooperative ClassificationE21B43/247
European ClassificationE21B43/247