|Publication number||US3358756 A|
|Publication date||Dec 19, 1967|
|Filing date||Mar 12, 1965|
|Priority date||Mar 12, 1965|
|Publication number||US 3358756 A, US 3358756A, US-A-3358756, US3358756 A, US3358756A|
|Inventors||Vogel John V|
|Original Assignee||Shell Oil Co|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (7), Referenced by (190), Classifications (11)|
|External Links: USPTO, USPTO Assignment, Espacenet|
Dec. 19, 1967 .1. v. VOGEL 3,358,756
METHOD FOR 1N slTU RECOVERY OF SOLID OR SEMI-SOLID PETROLEUM DEPOSITS Filed March 12, 1965 l? le f 2o E HEAT I f H HEATER ExcHANGER :HITQ Il ISG i PRODUCT\ LINE SEPARATION HIS ATTORNEY United States Patent O 3,358,756 .METHOD FR I-N SITU RECGVERY F SOLID 0R SEMI-SOLID PETROLEUM DEPOSITS John V. Vogel, Houston, Tex., assignor to Shell Oil Company, New York, N.Y., a corporation of Delaware Filed Mar. 12, 1965, Ser. No. 439,169 3 Claims. (Cl. 166-7) ABSTRACT 0F THE DISCLOSURE This invention relates to the recovery of petroleum existing in a solid or semi-solid state from underground deposits, and more particularly, to a method of in situ recovery involving -a cracking operation for converting solid or semi-solid petroleum deposits into useful and recoverable hydrocarbon products.
' Substantial petroleum deposits exist in solid or semi- -solid form and these deposits, the so-called oil shale deposits, are the greatest oil reserves in the United States. These deposits were formed apparently from fresh water lakes in which organic matter, mostly of algal origin, collected with nely divided silt at the bottom of Y fresh water lakes. This organic matter subsequently dried, became compacted and was transformed into a laminated, impermeable organic-bearing mineral matrix known today as oil shale.
The existence of the petroleum in such a semi-solid vf orm is not conducive to economic recovery by .present day techniques but,` 'because of the extensiveness of these oilshale deposits they provide more than an adequate incentive to develop means of recovering the oil therefrom. For example, -the Green River formation, located midway between Denver and Salt Lake City, extends f o ver some 16,500 square miles, averaging 15 or more gallons of desirable shale oil per ton. This isv probably the worlds single largest known hydrocarbon deposit with estimated reservesuof over 150,000,000,000 barrels.
"Presently, there are two broad approaches to the re- `cover-y of shale oil from the organic-inorganic matrix lknown as oil shale. One is retort of mined Ashale and the other is in situ treatment of the shale. Most successful today of the two general types of processes is the treate ment. of mined shale by retort processes. The diculty with such a process is that a 50,000 barrel per day plant requires that 84,000 tons of raw, good grade, shale be :processed through the plant per day and that 71,000 tonsk of inorganic residue be-disposed of daily. Thus, the materials handling pro'blems in such a process is enormous.
Because the organic matter in oil shale exists largely .as an insoluble residue, often referred to as kerogen, having a molecular Weight of 3000 plus, it is dillcult to separate the organic matter from the inorganic matter without some modification of the kerogen. Heat converts it into a liquid or vapor form. This is the reason that retort processes mentioned -above are more successful than other types. These retort processes involving mining the oil shale, transporting the shale to a suitable processing v point, crushing and grinding the shale to a particle size permitting effective heat treatment and thereafter heating the resulting particles sufficiently to effect destructive distillation of the kerogen are not today economical.
Even though the potential recovery of shale oil may be as high as 50 to 75 gallons per ton, material handling problems have caused industry to look for other methods of recovering the oil products from oil shales. This has led to the second lbroad approach to the recovery of organic matter which involves attempts to heat the oil shales in situ to recover the useful organic matter. These latter techniques are much akin to the retort process and, in fact, many use in situ retort processes either burning the organic matter in the shale or providing fuel within the formation to develop sui-licient heat to cause destructive distillation thereby converting it to either recoverable liquid or vapor products.
While the in situ combustion processes eliminate the costly operations of mining, transportation and processing of the raw oil shale, the virgin oil shale is very strong and impermeable in its natural occurring state which adds other problems. It is difficult to establish in situ combustion and to maintain it once it has been initiated Another problem faced with in situ oil shale combustions When this art is used is that the produced gases are highly contaminated with nitrogen which may reduce their fuel val-ue almost to nothing. Another diculty with in situ combustions is the presence of both magnesium carbonate and calcium carbonate which begin to calcine from about 1100 to about l500 F. via an endothermic reaction Which is also undesirable.
Since both of the general techniques discussed abovehave their own unique problems, other approaches to the recovery of organic matter from oil shale have been sought. The present invention has resulted from efforts to find a better technique to recover the organic matter from the oil shale and avoid some of the serious drawbacks of the aforedescribed techniques.
Broadly, the invention involves a new method of recovering solid to semi-solid organic matter from underground formations, such as oil shale deposits, including the steps of penetrating the formation with at least one injection well and at least one production well, fracturing the formation between said wells, injecting a non-oxidizing heated vapor through the injection well, and recovering eflluents from the production well which includes organic materials formed from the solid to semisolid organic matter in the formation by a thermal cracking action.
This invention will be better understood by referring to the attached drawing showing an earthen formation, taken in cross-section, including an underground oil shale deposit and also the necessary surface equipment for practicing themethod of the present invention.
Because the present invention is particularly applicable to recovery of organic matter from oil shales, some of the characteristics of such shales should be considered. Generally, the inorganic material of oil shales is a laminated marlstone intimately mixed with clay and lesser quantities of sediment, plus other mineral constituents. The organic matter. in a semi-pure form (often referred to as kerogen) is a brown amorphous powder having a molecular weight of 3000 plus. Because of this high molecular weight, kerogen is insoluble in common petroleum solvents at ambient temperatures and structurally appears to be a molecular complex of saturated, basically non-benzenoid, condensed polycyclic ring systems loosely interconnected through -alkyl side chains which may include hetero atoms.
Because of this nature of oilshales, the only industrial successful process to date is destructive pyrolysis of crushed oil shale at temperatures in the order of 900 F. and at ambient pressures. In pyrolysis, about 66% of the organic matter is converted to a liquid oil and 9% is converted to light gases with the remaining 25% sticking to the inorganic matrix as a carbon-rich residue.
The process of the instant invention is specifically adapted to avoid the necessity of mining the oil shale and processing it in a retort as known commercially successful processes would require. Instead the instant invention uses a hot vapor circulated through a fracture between two wells to transfer heat underground. Heat is carried away from the hot fracture and into the oil shale formation by conduction, aided somewhat by convection. When sufficient heat has been transferred to raise the oil shale to a sufcient temperature, the organic matter undergoes thermal cracking. The vapor pressure of the hot newly formed products causes them to expand and be forced out of the shale and into the fracture, adjacent permeable zones and/or the producing well. This process is aided somewhat by a sweeping action of the hot vapor circulated as the heat carrying medium.
By properly controlling temperatures and withdrawal rates, the degree of cracking of the organic matter can be controlled so as to favor poduction of gas or oil. Generally speaking, gas products are favored -by higher temperatures and/or long exposure of the organic matter to the cracking temperatures.
It may be preferred, but is not essential that the hot vapor, or a portion thereof, be an organic material which, rwhile not miscible with the insoluble kerogen, is miscible with the cracked products obtained by circulating the hot vapor through the shale formation. Since the pyrolysis of the organic matter in the oil shale produces heavy cornponents Iwhich can be very viscous when in contact with cooler portions of the underground system, the misci'bility of the hot vapor with the liquid conversion products may tend to lessen their viscosity and allow them to drain more freely from the inorganic matrix into the fractures, adjacent permeable zones, and/or the producing well.
It is desirable that the vapor injected have good heat carrying capacity in the temperature range of 650 to l100 F. This eliminates superheated steam which is somewhat limited in its ability to carry heat and is nonmiscible with the oil products. Vaporous hydrocarbons, therefore, are especially desirable for carrying out the process. Further, an advantage is gained by using vaporous hydrocarbons since such hydrocarbons can be obtained on location for the use in the process which elirninates the requirement for large volumes of fresh water which would be difficult to find in the arid region where oil shales are common.
In the practice of this invention, it is desirable that light hydrocarbons which are themselves resistant to thermal cracking, be employed in the vaporous phase to recover the organic matter from the undergound oil shale deposits. Generally, suitable hydrocarbons are methane, ethane, propane, butane, kerosene, naphtha, gasoline, benzene, and the like. Benzene, butane and propane combine a high heat carrying capacity with good resistance to thermal crackin-g. Another suitable mixture of gases which is even more resistant to thermal cracking, although of somewhat lower heat carrying capacity, is the gas produced by the process itself as the 4kerogen undergoes .destruction distillation (hereafter termed shale gas). Because of the good heat carrying capacity of the hydrocarbons referred to above plus their miscibility with the liquid products formed from the thermal cracking, they are able to achieve better cracking efficiency and removal of products than immiscible superheated steam. Because the use of steam, especially at the temperatures involved, can cause unwanted tectonic changes to occur within the formation that are not likely to occur with the vaporous hydrocarbons, steam is not suitable in the instant invention.
Generally, it is desired that the vaporous hydrocarbons be injected into the formation at temperatures in excess of 700 F. In fact, it is very desirable to heat the hydrocarbon vapors to a temperature well above 700 F. in order to maintain the temperature in the area of central ow between the two spaced wells at a temperature of at 4 least 700 F. Generally, the upper limit to which the vaporous hydrocarbons can be raised is limited to that point at which they themselves undergo thermal cracking or suffer degradation and this will depend largely upon the particular hydrocarbon employed in the process.
For a better understanding of the invention, reference is made to the single accompanying gure showing an earthen formation in cross-section penetrated by two spaced wells. The earthen formation 1 is composed of a plurality of strata and includes a reservoir formation 2 composed principally of oil shale. In practicing this invention, at least one injection well 3 and at least one production well 4 are drilled through the earthen formation to penetrate the shale formation Z. The illustrated construction of both the injection well and the production well 3 and 4, respectively, is quite similar, each having a casing 5 positioned in the borehole and sealed with a sealant `6 to maintain its location therein. Inside each casing string 5 is an insulated tubing string 7 which is positioned in the casing string to leave insulating annulus therebetween which is sealed near the lower end of the tubing string 7 by packer 8.
Below packer 8, the casing string 5 is perforated in order to provide uid ingress and egress between the inside of the casing string 5 and the shale formation 2. It is generally preferred that the casing string actually be severed in the area of the perforations since this portion of the casin-g string will be subjected to high temperatures and this allows for expansion of the casing string.
Since, in all probability, the shale formation 2 will be impermeable, it will be necessary to fracture between the input well 3 and the production well 4. Fracture 9 can be established by the use of hydraulic fracturing fluids and can be propped with propping agents 10 to insure that it remains open during the injection of the hot hydrocarbon vapors. Not only may it be desirable to use propping agents 10, it may be necessary because of the expansion of the oil shale when heated which would tend to collapse the fracture if no propping agents are rpresent.
As it is desired that the hot hydrocarbon vapors be continuously recycled through the formation to etect the recovery of the organic matter therein, the discussion of the above ground equipment will begin with the effluents of production well 4 and terminate with the injection of the hot hydrocarbon vapors through injection well 3. At the wellhead 11 of casing string 5 of the production well, the vaporous eiuents are recovered through the insulated tubing string 7, pass through line 12 and go .directly to heat exchanger 13 and thence into a separating facility 14 in which the cracked products from the formation are separated from the hot hydrocarbon which was injected through the injection well 3 to recover these products. Depending on the particular hydrocarbon mixture used, the separation facility 14 may consist of simple conventional equipment for separating gases and liquids by gravity or may require somewhat more elaborate distillation and condensation equipment. The oil and gas products are recovered through product recovery lines 15 and 15a and the heat carrying hydrocarbon, which was injected in vapor form, is removed from the separating facility 14 by line 16 and goes directly to heat exchanger 13 and then through line 17 to pump or compressor 18. From pump or compressor 18, the hydrocarbon passes directly to a suitable heater 19 via line 20 wherein the hydrocarbon is raised to a temperature in excess -of 700 F.
From heater 19, the heated hydrocarbon vapors are routed via insulated pipe 21 to the wellhead 22 of the injection well 3. There the hot vaporous hydrocarbon travels down the insulated tubing string '7 of injection well 3 and proceeds via the tubing string and perforations 23 to fracture 9. From the perforations 23 in casing string 5 of the lower portion of injection well 3, the hot hydrocarbons enter fracture 9 and transmit their heat by conduction and/or convection to the oil shale formation adjacent to the fracture. As these hot hydrocarbon vapors ow through the fracture 9 to the production Well 4, some of the organic matter in the oil shale formation is thermally cracked to lower boiling products which are much less viscous. Once the cracked products from the organic matter in the formation are reduced to low viscosity products and/'or vaporized, they are forced out of their original position by expanding vapor pressure and swept along lwith the hot hydrocarbon to the production well from whence they are recovered via tubing string 7. As the circulation continues, the area of the shale formation 2 adjacent t-o fracture 9 will become depleted of much of the organic matter as indicated by the depleted zone 24. As the areas adjacent to fracture become depleted organic matter, it will become permeable to the hot hydrocarbon vapors allowing them to contact more virgin shale.
In the instant process, since the circulation of the hydrocarbon occurs in a closed circulatory system, little if any oxygen is available for actual in situ combustion which would occur at the temperatures in the formation if oxygen were present. Further, even if some oxygen is available within the formation, it is of little or no moment, since an extremely limited amount will be available to support combustion. Actual combustion in the formation is not desired since it could adversely affect permeability.
Though we have discussed the invention relative to the use of two spaced wells, one of which is the injection well and one of which is the production well, it should be appreciated that it would be possible to carry out the instant process in a single Well with dual insulated tubing strings and through a vertical fracture.
Further, it should be appreciated that the facilities located above the ground would all involve appropriate insulation in order to conserve thermal energy and the use of appropriate heat exchangers in order to recover the maximum amount of thermal energy from the eluents from the production well. In this way, the efficiency of the process can be improved and it can be operated on a commercial scale.
As the circulation of the hot hydrocarbons continues through the oil shale formation 2, the depleted zone 24 continues to expand as more and more of the organic matter is stripped therefrom. In some cases, it may be desirable to establish a fracture 9 at multiple levels in order to optimize the effects of this process in the formation and to allow for irregularities in the formation itself. When the fractures are employed at multiple levels, the hot hydrocarbons can be injected into the fractures separately or simultaneously but usually separately in order to avoid failure of the casing string resulting from a large segment thereof being exposed to the relatively high temperatures. To avoid simultaneous injections or exposing large areas of the casing to high temperatures, a lower packer 25 may be used in each casing 5.
In order that the invention can be better understood, the following example is illustrative of the instant invention and method of carrying it out.
Example I In a mathematical model, it was determined that 950 F. benzene vapors injected into a shale formation through an injection well and recovered at a production Well at 650 F. would give 55,000 B.t.u.s/bbl. to the formation. Calculated on four acre spacing with wells 300 feet apart and having liuid communication therebetween through the oil shale, an injection of 3260 barrels per day of 950 F. benzene vapors into fractures between the Wells will raise the temperature of a portion of the shale formation 25 feet on each side of the fracture to 750 F. within four years. The pressure drop will be 200l p.s.i. between the wells. If the shale has a richness of 30 gallons/ton of virgin oil shale, 442,000 bbls. of oil (or vaporous hydrocarbon equivalent) would be given out of the four acre- 50 foot interval during the four year period. An average of 300 bbls./day for the producing wells for the period.
The foregoing example is based on calculations and is not intended to limit the invention. Various changes in injection rates and temperatures will probably be necessary depending on the particular shale formations and the gaseous eiiluents (shale gas) recovered from the formation will probably be the most economical vapor to use in the instant process.
I claim as my invention:
-1. A method of recovering solid to semi-solid hydrocarbons from uniform underground oil shale reservoirs comprising the steps of:
(a) pentrating such a reservoir with at least one in- -jection well and at least one production well;
(b) horizontally fracturing and establishing iluid communication channels through said reservoir between said injection well and said production well;
(c) passing hot benzene through said reservoir by injecting it through said fractured injecting Well into said uid communication channels at a temperature in excess of 650 F. to convert solid to semi-solid hydrocarbon residues in said formation to mobile fluids;
(d) recovering said mobile uids from said production Well; and
(e) separating said mobile iiuids into liquid and gaseous hydrocarbon fractions.
2. A method according to claim 1 in which a conventional propping agent is added to the fractures.
3. A method according to claim 1 in which the ilow rate through the reservoir and the temperature of the hot benzene is controlled so that the solid to semi-solid hydrocarbons are substantially converted to hydrocarbon vapor and which are recovered above ground, condensed and fractionated into liquid hydrocarbon oil and hydrocarbon gases.
References Cited UNITED STATES PATENTS 895,612 8/1908 Baker 166-57 1,422,204 7/ 1922 Hoover et al. 166-11 2,813,583` 11/1957 Marx et al. 166-11 2,974,937 3/1961 Kiel 166--11 X 3,145,772 8/1964 Huitt 166-7 X 3,241,611 3/1966 Dougan 166-11 X 3,284,281 11/1966 Thomas 166--11 X STEPHEN J. NOV OSAD, Primary Examiner.
|Cited Patent||Filing date||Publication date||Applicant||Title|
|US895612 *||Jun 11, 1902||Aug 11, 1908||Delos R Baker||Apparatus for extracting the volatilizable contents of sedimentary strata.|
|US1422204 *||Dec 19, 1919||Jul 11, 1922||Brown Thomas E||Method for working oil shales|
|US2813583 *||Dec 6, 1954||Nov 19, 1957||Phillips Petroleum Co||Process for recovery of petroleum from sands and shale|
|US2974937 *||Nov 3, 1958||Mar 14, 1961||Jersey Prod Res Co||Petroleum recovery from carbonaceous formations|
|US3145772 *||Sep 13, 1962||Aug 25, 1964||Gulf Research Development Co||Temperature controlled in-situ combustion process|
|US3241611 *||Apr 10, 1963||Mar 22, 1966||Equity Oil Company||Recovery of petroleum products from oil shale|
|US3284281 *||Aug 31, 1964||Nov 8, 1966||Phillips Petroleum Co||Production of oil from oil shale through fractures|
|Citing Patent||Filing date||Publication date||Applicant||Title|
|US3451479 *||Jun 12, 1967||Jun 24, 1969||Phillips Petroleum Co||Insulating a casing and tubing string in an oil well for a hot fluid drive|
|US3474863 *||Jul 28, 1967||Oct 28, 1969||Shell Oil Co||Shale oil extraction process|
|US3512585 *||Aug 8, 1968||May 19, 1970||Texaco Inc||Method of recovering hydrocarbons by in situ vaporization of connate water|
|US3513914 *||Sep 30, 1968||May 26, 1970||Shell Oil Co||Method for producing shale oil from an oil shale formation|
|US3515213 *||Apr 19, 1967||Jun 2, 1970||Shell Oil Co||Shale oil recovery process using heated oil-miscible fluids|
|US3528501 *||Aug 4, 1967||Sep 15, 1970||Phillips Petroleum Co||Recovery of oil from oil shale|
|US3557871 *||Sep 30, 1968||Jan 26, 1971||Phillips Petroleum Co||Insulated casing and tubing string in an oil well for a hot fluid drive|
|US3593790 *||Jan 2, 1969||Jul 20, 1971||Shell Oil Co||Method for producing shale oil from an oil shale formation|
|US3608638 *||Dec 23, 1969||Sep 28, 1971||Gulf Research Development Co||Heavy oil recovery method|
|US3666014 *||Dec 29, 1969||May 30, 1972||Shell Oil Co||Method for the recovery of shale oil|
|US3675715 *||Dec 30, 1970||Jul 11, 1972||Forrester A Clark||Processes for secondarily recovering oil|
|US3730270 *||Mar 23, 1971||May 1, 1973||Marathon Oil Co||Shale oil recovery from fractured oil shale|
|US3804169 *||Feb 7, 1973||Apr 16, 1974||Shell Oil Co||Spreading-fluid recovery of subterranean oil|
|US3881550 *||May 24, 1973||May 6, 1975||Parsons Co Ralph M||In situ recovery of hydrocarbons from tar sands|
|US3945435 *||Nov 7, 1974||Mar 23, 1976||The Ralph M. Parsons Co.||In situ recovery of hydrocarbons from tar sands|
|US3946810 *||Nov 7, 1974||Mar 30, 1976||The Ralph M. Parsons Company||In situ recovery of hydrocarbons from tar sands|
|US4087130 *||Apr 14, 1977||May 2, 1978||Occidental Petroleum Corporation||Process for the gasification of coal in situ|
|US4362213 *||Nov 19, 1980||Dec 7, 1982||Hydrocarbon Research, Inc.||Method of in situ oil extraction using hot solvent vapor injection|
|US4396064 *||May 14, 1981||Aug 2, 1983||Atlantic Richfield Company||Method and apparatus for injecting a gaseous stream into a subterranean zone|
|US4399867 *||May 14, 1981||Aug 23, 1983||Atlantic Richfield Company||Method for injecting a gaseous stream into a hot subterranean zone|
|US4407367 *||Oct 14, 1980||Oct 4, 1983||Hri, Inc.||Method for in situ recovery of heavy crude oils and tars by hydrocarbon vapor injection|
|US4438816 *||May 13, 1982||Mar 27, 1984||Uop Inc.||Process for recovery of hydrocarbons from oil shale|
|US4446921 *||Mar 16, 1982||May 8, 1984||Fried. Krupp Gesellschaft Mit Beschrankter Haftung||Method for underground gasification of solid fuels|
|US4449586 *||Jun 11, 1982||May 22, 1984||Uop Inc.||Process for the recovery of hydrocarbons from oil shale|
|US4450913 *||Jun 14, 1982||May 29, 1984||Texaco Inc.||Superheated solvent method for recovering viscous petroleum|
|US4484630 *||Mar 8, 1983||Nov 27, 1984||Mobil Oil Corporation||Method for recovering heavy crudes from shallow reservoirs|
|US5014787 *||Aug 16, 1989||May 14, 1991||Chevron Research Company||Single well injection and production system|
|US7360588 *||Oct 17, 2006||Apr 22, 2008||Shell Oil Company||Thermal processes for subsurface formations|
|US7441603||Jul 30, 2004||Oct 28, 2008||Exxonmobil Upstream Research Company||Hydrocarbon recovery from impermeable oil shales|
|US7644765||Oct 19, 2007||Jan 12, 2010||Shell Oil Company||Heating tar sands formations while controlling pressure|
|US7673681||Oct 19, 2007||Mar 9, 2010||Shell Oil Company||Treating tar sands formations with karsted zones|
|US7673786||Apr 20, 2007||Mar 9, 2010||Shell Oil Company||Welding shield for coupling heaters|
|US7677310||Oct 19, 2007||Mar 16, 2010||Shell Oil Company||Creating and maintaining a gas cap in tar sands formations|
|US7677314||Oct 19, 2007||Mar 16, 2010||Shell Oil Company||Method of condensing vaporized water in situ to treat tar sands formations|
|US7681647||Oct 19, 2007||Mar 23, 2010||Shell Oil Company||Method of producing drive fluid in situ in tar sands formations|
|US7683296||Apr 20, 2007||Mar 23, 2010||Shell Oil Company||Adjusting alloy compositions for selected properties in temperature limited heaters|
|US7703513||Oct 19, 2007||Apr 27, 2010||Shell Oil Company||Wax barrier for use with in situ processes for treating formations|
|US7717171||Oct 19, 2007||May 18, 2010||Shell Oil Company||Moving hydrocarbons through portions of tar sands formations with a fluid|
|US7730945||Oct 19, 2007||Jun 8, 2010||Shell Oil Company||Using geothermal energy to heat a portion of a formation for an in situ heat treatment process|
|US7730946||Oct 19, 2007||Jun 8, 2010||Shell Oil Company||Treating tar sands formations with dolomite|
|US7730947||Oct 19, 2007||Jun 8, 2010||Shell Oil Company||Creating fluid injectivity in tar sands formations|
|US7785427||Apr 20, 2007||Aug 31, 2010||Shell Oil Company||High strength alloys|
|US7793722||Apr 20, 2007||Sep 14, 2010||Shell Oil Company||Non-ferromagnetic overburden casing|
|US7798220||Apr 18, 2008||Sep 21, 2010||Shell Oil Company||In situ heat treatment of a tar sands formation after drive process treatment|
|US7798221||May 31, 2007||Sep 21, 2010||Shell Oil Company||In situ recovery from a hydrocarbon containing formation|
|US7831133||Apr 21, 2006||Nov 9, 2010||Shell Oil Company||Insulated conductor temperature limited heater for subsurface heating coupled in a three-phase WYE configuration|
|US7831134||Apr 21, 2006||Nov 9, 2010||Shell Oil Company||Grouped exposed metal heaters|
|US7832484||Apr 18, 2008||Nov 16, 2010||Shell Oil Company||Molten salt as a heat transfer fluid for heating a subsurface formation|
|US7841401||Oct 19, 2007||Nov 30, 2010||Shell Oil Company||Gas injection to inhibit migration during an in situ heat treatment process|
|US7841408||Apr 18, 2008||Nov 30, 2010||Shell Oil Company||In situ heat treatment from multiple layers of a tar sands formation|
|US7841425||Apr 18, 2008||Nov 30, 2010||Shell Oil Company||Drilling subsurface wellbores with cutting structures|
|US7845411||Oct 19, 2007||Dec 7, 2010||Shell Oil Company||In situ heat treatment process utilizing a closed loop heating system|
|US7849922||Apr 18, 2008||Dec 14, 2010||Shell Oil Company||In situ recovery from residually heated sections in a hydrocarbon containing formation|
|US7857056||Oct 15, 2008||Dec 28, 2010||Exxonmobil Upstream Research Company||Hydrocarbon recovery from impermeable oil shales using sets of fluid-heated fractures|
|US7860377||Apr 21, 2006||Dec 28, 2010||Shell Oil Company||Subsurface connection methods for subsurface heaters|
|US7866385||Apr 20, 2007||Jan 11, 2011||Shell Oil Company||Power systems utilizing the heat of produced formation fluid|
|US7866386||Oct 13, 2008||Jan 11, 2011||Shell Oil Company||In situ oxidation of subsurface formations|
|US7866388||Oct 13, 2008||Jan 11, 2011||Shell Oil Company||High temperature methods for forming oxidizer fuel|
|US7912358||Apr 20, 2007||Mar 22, 2011||Shell Oil Company||Alternate energy source usage for in situ heat treatment processes|
|US7931086||Apr 18, 2008||Apr 26, 2011||Shell Oil Company||Heating systems for heating subsurface formations|
|US7942203||Jan 4, 2010||May 17, 2011||Shell Oil Company||Thermal processes for subsurface formations|
|US7950453||Apr 18, 2008||May 31, 2011||Shell Oil Company||Downhole burner systems and methods for heating subsurface formations|
|US7980312 *||Jun 19, 2006||Jul 19, 2011||Hill Gilman A||Integrated in situ retorting and refining of oil shale|
|US7986869||Apr 21, 2006||Jul 26, 2011||Shell Oil Company||Varying properties along lengths of temperature limited heaters|
|US8011451||Oct 13, 2008||Sep 6, 2011||Shell Oil Company||Ranging methods for developing wellbores in subsurface formations|
|US8027571||Apr 21, 2006||Sep 27, 2011||Shell Oil Company||In situ conversion process systems utilizing wellbores in at least two regions of a formation|
|US8042610||Apr 18, 2008||Oct 25, 2011||Shell Oil Company||Parallel heater system for subsurface formations|
|US8082995||Nov 14, 2008||Dec 27, 2011||Exxonmobil Upstream Research Company||Optimization of untreated oil shale geometry to control subsidence|
|US8083813||Apr 20, 2007||Dec 27, 2011||Shell Oil Company||Methods of producing transportation fuel|
|US8087460||Mar 7, 2008||Jan 3, 2012||Exxonmobil Upstream Research Company||Granular electrical connections for in situ formation heating|
|US8113272||Oct 13, 2008||Feb 14, 2012||Shell Oil Company||Three-phase heaters with common overburden sections for heating subsurface formations|
|US8122955||Apr 18, 2008||Feb 28, 2012||Exxonmobil Upstream Research Company||Downhole burners for in situ conversion of organic-rich rock formations|
|US8146661||Oct 13, 2008||Apr 3, 2012||Shell Oil Company||Cryogenic treatment of gas|
|US8146664||May 21, 2008||Apr 3, 2012||Exxonmobil Upstream Research Company||Utilization of low BTU gas generated during in situ heating of organic-rich rock|
|US8146669||Oct 13, 2008||Apr 3, 2012||Shell Oil Company||Multi-step heater deployment in a subsurface formation|
|US8151877||Apr 18, 2008||Apr 10, 2012||Exxonmobil Upstream Research Company||Downhole burner wells for in situ conversion of organic-rich rock formations|
|US8151880||Dec 9, 2010||Apr 10, 2012||Shell Oil Company||Methods of making transportation fuel|
|US8151884||Oct 10, 2007||Apr 10, 2012||Exxonmobil Upstream Research Company||Combined development of oil shale by in situ heating with a deeper hydrocarbon resource|
|US8151907||Apr 10, 2009||Apr 10, 2012||Shell Oil Company||Dual motor systems and non-rotating sensors for use in developing wellbores in subsurface formations|
|US8162059||Oct 13, 2008||Apr 24, 2012||Shell Oil Company||Induction heaters used to heat subsurface formations|
|US8162405||Apr 10, 2009||Apr 24, 2012||Shell Oil Company||Using tunnels for treating subsurface hydrocarbon containing formations|
|US8172335||Apr 10, 2009||May 8, 2012||Shell Oil Company||Electrical current flow between tunnels for use in heating subsurface hydrocarbon containing formations|
|US8177305||Apr 10, 2009||May 15, 2012||Shell Oil Company||Heater connections in mines and tunnels for use in treating subsurface hydrocarbon containing formations|
|US8191630||Apr 28, 2010||Jun 5, 2012||Shell Oil Company||Creating fluid injectivity in tar sands formations|
|US8192682||Apr 26, 2010||Jun 5, 2012||Shell Oil Company||High strength alloys|
|US8196658||Oct 13, 2008||Jun 12, 2012||Shell Oil Company||Irregular spacing of heat sources for treating hydrocarbon containing formations|
|US8200072||Oct 24, 2003||Jun 12, 2012||Shell Oil Company||Temperature limited heaters for heating subsurface formations or wellbores|
|US8220539||Oct 9, 2009||Jul 17, 2012||Shell Oil Company||Controlling hydrogen pressure in self-regulating nuclear reactors used to treat a subsurface formation|
|US8224163||Oct 24, 2003||Jul 17, 2012||Shell Oil Company||Variable frequency temperature limited heaters|
|US8224164||Oct 24, 2003||Jul 17, 2012||Shell Oil Company||Insulated conductor temperature limited heaters|
|US8224165||Apr 21, 2006||Jul 17, 2012||Shell Oil Company||Temperature limited heater utilizing non-ferromagnetic conductor|
|US8225866||Jul 21, 2010||Jul 24, 2012||Shell Oil Company||In situ recovery from a hydrocarbon containing formation|
|US8230927||May 16, 2011||Jul 31, 2012||Shell Oil Company||Methods and systems for producing fluid from an in situ conversion process|
|US8230929||Mar 17, 2009||Jul 31, 2012||Exxonmobil Upstream Research Company||Methods of producing hydrocarbons for substantially constant composition gas generation|
|US8233782||Sep 29, 2010||Jul 31, 2012||Shell Oil Company||Grouped exposed metal heaters|
|US8238730||Oct 24, 2003||Aug 7, 2012||Shell Oil Company||High voltage temperature limited heaters|
|US8240774||Oct 13, 2008||Aug 14, 2012||Shell Oil Company||Solution mining and in situ treatment of nahcolite beds|
|US8256512||Oct 9, 2009||Sep 4, 2012||Shell Oil Company||Movable heaters for treating subsurface hydrocarbon containing formations|
|US8261823||May 11, 2011||Sep 11, 2012||Hill Gilman A||Integrated in situ retorting and refining of oil shale|
|US8261832||Oct 9, 2009||Sep 11, 2012||Shell Oil Company||Heating subsurface formations with fluids|
|US8267170||Oct 9, 2009||Sep 18, 2012||Shell Oil Company||Offset barrier wells in subsurface formations|
|US8267185||Oct 9, 2009||Sep 18, 2012||Shell Oil Company||Circulated heated transfer fluid systems used to treat a subsurface formation|
|US8272455||Oct 13, 2008||Sep 25, 2012||Shell Oil Company||Methods for forming wellbores in heated formations|
|US8276661||Oct 13, 2008||Oct 2, 2012||Shell Oil Company||Heating subsurface formations by oxidizing fuel on a fuel carrier|
|US8281861||Oct 9, 2009||Oct 9, 2012||Shell Oil Company||Circulated heated transfer fluid heating of subsurface hydrocarbon formations|
|US8327681||Apr 18, 2008||Dec 11, 2012||Shell Oil Company||Wellbore manufacturing processes for in situ heat treatment processes|
|US8327932||Apr 9, 2010||Dec 11, 2012||Shell Oil Company||Recovering energy from a subsurface formation|
|US8353347||Oct 9, 2009||Jan 15, 2013||Shell Oil Company||Deployment of insulated conductors for treating subsurface formations|
|US8355623||Apr 22, 2005||Jan 15, 2013||Shell Oil Company||Temperature limited heaters with high power factors|
|US8381815||Apr 18, 2008||Feb 26, 2013||Shell Oil Company||Production from multiple zones of a tar sands formation|
|US8434555||Apr 9, 2010||May 7, 2013||Shell Oil Company||Irregular pattern treatment of a subsurface formation|
|US8448707||Apr 9, 2010||May 28, 2013||Shell Oil Company||Non-conducting heater casings|
|US8459359||Apr 18, 2008||Jun 11, 2013||Shell Oil Company||Treating nahcolite containing formations and saline zones|
|US8485252||Jul 11, 2012||Jul 16, 2013||Shell Oil Company||In situ recovery from a hydrocarbon containing formation|
|US8536497||Oct 13, 2008||Sep 17, 2013||Shell Oil Company||Methods for forming long subsurface heaters|
|US8540020||Apr 21, 2010||Sep 24, 2013||Exxonmobil Upstream Research Company||Converting organic matter from a subterranean formation into producible hydrocarbons by controlling production operations based on availability of one or more production resources|
|US8555971||May 31, 2012||Oct 15, 2013||Shell Oil Company||Treating tar sands formations with dolomite|
|US8562078||Nov 25, 2009||Oct 22, 2013||Shell Oil Company||Hydrocarbon production from mines and tunnels used in treating subsurface hydrocarbon containing formations|
|US8579031||May 17, 2011||Nov 12, 2013||Shell Oil Company||Thermal processes for subsurface formations|
|US8596355||Dec 10, 2010||Dec 3, 2013||Exxonmobil Upstream Research Company||Optimized well spacing for in situ shale oil development|
|US8606091||Oct 20, 2006||Dec 10, 2013||Shell Oil Company||Subsurface heaters with low sulfidation rates|
|US8608249||Apr 26, 2010||Dec 17, 2013||Shell Oil Company||In situ thermal processing of an oil shale formation|
|US8616279||Jan 7, 2010||Dec 31, 2013||Exxonmobil Upstream Research Company||Water treatment following shale oil production by in situ heating|
|US8616280||Jun 17, 2011||Dec 31, 2013||Exxonmobil Upstream Research Company||Wellbore mechanical integrity for in situ pyrolysis|
|US8622127||Jun 17, 2011||Jan 7, 2014||Exxonmobil Upstream Research Company||Olefin reduction for in situ pyrolysis oil generation|
|US8622133||Mar 7, 2008||Jan 7, 2014||Exxonmobil Upstream Research Company||Resistive heater for in situ formation heating|
|US8627887||Dec 8, 2008||Jan 14, 2014||Shell Oil Company||In situ recovery from a hydrocarbon containing formation|
|US8631866||Apr 8, 2011||Jan 21, 2014||Shell Oil Company||Leak detection in circulated fluid systems for heating subsurface formations|
|US8636323||Nov 25, 2009||Jan 28, 2014||Shell Oil Company||Mines and tunnels for use in treating subsurface hydrocarbon containing formations|
|US8641150||Dec 11, 2009||Feb 4, 2014||Exxonmobil Upstream Research Company||In situ co-development of oil shale with mineral recovery|
|US8662175||Apr 18, 2008||Mar 4, 2014||Shell Oil Company||Varying properties of in situ heat treatment of a tar sands formation based on assessed viscosities|
|US8701768||Apr 8, 2011||Apr 22, 2014||Shell Oil Company||Methods for treating hydrocarbon formations|
|US8701769||Apr 8, 2011||Apr 22, 2014||Shell Oil Company||Methods for treating hydrocarbon formations based on geology|
|US8701788||Dec 22, 2011||Apr 22, 2014||Chevron U.S.A. Inc.||Preconditioning a subsurface shale formation by removing extractible organics|
|US8739874||Apr 8, 2011||Jun 3, 2014||Shell Oil Company||Methods for heating with slots in hydrocarbon formations|
|US8752904||Apr 10, 2009||Jun 17, 2014||Shell Oil Company||Heated fluid flow in mines and tunnels used in heating subsurface hydrocarbon containing formations|
|US8770284||Apr 19, 2013||Jul 8, 2014||Exxonmobil Upstream Research Company||Systems and methods of detecting an intersection between a wellbore and a subterranean structure that includes a marker material|
|US8789586||Jul 12, 2013||Jul 29, 2014||Shell Oil Company||In situ recovery from a hydrocarbon containing formation|
|US8791396||Apr 18, 2008||Jul 29, 2014||Shell Oil Company||Floating insulated conductors for heating subsurface formations|
|US8820406||Apr 8, 2011||Sep 2, 2014||Shell Oil Company||Electrodes for electrical current flow heating of subsurface formations with conductive material in wellbore|
|US8833453||Apr 8, 2011||Sep 16, 2014||Shell Oil Company||Electrodes for electrical current flow heating of subsurface formations with tapered copper thickness|
|US8839860||Dec 22, 2011||Sep 23, 2014||Chevron U.S.A. Inc.||In-situ Kerogen conversion and product isolation|
|US8851170||Apr 9, 2010||Oct 7, 2014||Shell Oil Company||Heater assisted fluid treatment of a subsurface formation|
|US8851177||Dec 22, 2011||Oct 7, 2014||Chevron U.S.A. Inc.||In-situ kerogen conversion and oxidant regeneration|
|US8857506||May 24, 2013||Oct 14, 2014||Shell Oil Company||Alternate energy source usage methods for in situ heat treatment processes|
|US8863839||Nov 15, 2010||Oct 21, 2014||Exxonmobil Upstream Research Company||Enhanced convection for in situ pyrolysis of organic-rich rock formations|
|US8875789||Aug 8, 2011||Nov 4, 2014||Exxonmobil Upstream Research Company||Process for producing hydrocarbon fluids combining in situ heating, a power plant and a gas plant|
|US8881806||Oct 9, 2009||Nov 11, 2014||Shell Oil Company||Systems and methods for treating a subsurface formation with electrical conductors|
|US8936089||Dec 22, 2011||Jan 20, 2015||Chevron U.S.A. Inc.||In-situ kerogen conversion and recovery|
|US8992771||May 25, 2012||Mar 31, 2015||Chevron U.S.A. Inc.||Isolating lubricating oils from subsurface shale formations|
|US8997869||Dec 22, 2011||Apr 7, 2015||Chevron U.S.A. Inc.||In-situ kerogen conversion and product upgrading|
|US9016370||Apr 6, 2012||Apr 28, 2015||Shell Oil Company||Partial solution mining of hydrocarbon containing layers prior to in situ heat treatment|
|US9022109||Jan 21, 2014||May 5, 2015||Shell Oil Company||Leak detection in circulated fluid systems for heating subsurface formations|
|US9022118||Oct 9, 2009||May 5, 2015||Shell Oil Company||Double insulated heaters for treating subsurface formations|
|US9033033||Dec 22, 2011||May 19, 2015||Chevron U.S.A. Inc.||Electrokinetic enhanced hydrocarbon recovery from oil shale|
|US9033042||Apr 8, 2011||May 19, 2015||Shell Oil Company||Forming bitumen barriers in subsurface hydrocarbon formations|
|US9051829||Oct 9, 2009||Jun 9, 2015||Shell Oil Company||Perforated electrical conductors for treating subsurface formations|
|US9080441||Oct 26, 2012||Jul 14, 2015||Exxonmobil Upstream Research Company||Multiple electrical connections to optimize heating for in situ pyrolysis|
|US9085972 *||Aug 6, 2012||Jul 21, 2015||Gilman A. Hill||Integrated in situ retorting and refining of heavy-oil and tar sand deposits|
|US9127523||Apr 8, 2011||Sep 8, 2015||Shell Oil Company||Barrier methods for use in subsurface hydrocarbon formations|
|US9127538||Apr 8, 2011||Sep 8, 2015||Shell Oil Company||Methodologies for treatment of hydrocarbon formations using staged pyrolyzation|
|US9129728||Oct 9, 2009||Sep 8, 2015||Shell Oil Company||Systems and methods of forming subsurface wellbores|
|US9133398||Dec 22, 2011||Sep 15, 2015||Chevron U.S.A. Inc.||In-situ kerogen conversion and recycling|
|US9181467 *||Dec 22, 2011||Nov 10, 2015||Uchicago Argonne, Llc||Preparation and use of nano-catalysts for in-situ reaction with kerogen|
|US9181780||Apr 18, 2008||Nov 10, 2015||Shell Oil Company||Controlling and assessing pressure conditions during treatment of tar sands formations|
|US9309755||Oct 4, 2012||Apr 12, 2016||Shell Oil Company||Thermal expansion accommodation for circulated fluid systems used to heat subsurface formations|
|US9309756||Nov 9, 2013||Apr 12, 2016||Joseph A Affholter||In situ retorting of hydrocarbons|
|US9347302||Nov 12, 2013||May 24, 2016||Exxonmobil Upstream Research Company||Resistive heater for in situ formation heating|
|US9394772||Sep 17, 2014||Jul 19, 2016||Exxonmobil Upstream Research Company||Systems and methods for in situ resistive heating of organic matter in a subterranean formation|
|US9399905||May 4, 2015||Jul 26, 2016||Shell Oil Company||Leak detection in circulated fluid systems for heating subsurface formations|
|US9429004||Nov 4, 2013||Aug 30, 2016||Joseph A. Affholter||In situ retorting and refining of hygrocarbons|
|US9512699||Jul 30, 2014||Dec 6, 2016||Exxonmobil Upstream Research Company||Systems and methods for regulating an in situ pyrolysis process|
|US9528322||Jun 16, 2014||Dec 27, 2016||Shell Oil Company||Dual motor systems and non-rotating sensors for use in developing wellbores in subsurface formations|
|US9644466||Oct 15, 2015||May 9, 2017||Exxonmobil Upstream Research Company||Method of recovering hydrocarbons within a subsurface formation using electric current|
|US20050269077 *||Apr 22, 2005||Dec 8, 2005||Sandberg Chester L||Start-up of temperature limited heaters using direct current (DC)|
|US20070023186 *||Jul 30, 2004||Feb 1, 2007||Kaminsky Robert D||Hydrocarbon recovery from impermeable oil shales|
|US20070045267 *||Apr 21, 2006||Mar 1, 2007||Vinegar Harold J||Subsurface connection methods for subsurface heaters|
|US20070045268 *||Apr 21, 2006||Mar 1, 2007||Vinegar Harold J||Varying properties along lengths of temperature limited heaters|
|US20070108201 *||Apr 21, 2006||May 17, 2007||Vinegar Harold J||Insulated conductor temperature limited heater for subsurface heating coupled in a three-phase wye configuration|
|US20070131411 *||Oct 17, 2006||Jun 14, 2007||Vinegar Harold J||Thermal processes for subsurface formations|
|US20070133959 *||Apr 21, 2006||Jun 14, 2007||Vinegar Harold J||Grouped exposed metal heaters|
|US20070133960 *||Apr 21, 2006||Jun 14, 2007||Vinegar Harold J||In situ conversion process systems utilizing wellbores in at least two regions of a formation|
|US20090038795 *||Oct 15, 2008||Feb 12, 2009||Kaminsky Robert D||Hydrocarbon Recovery From Impermeable Oil Shales Using Sets of Fluid-Heated Fractures|
|US20090071647 *||Apr 7, 2008||Mar 19, 2009||Vinegar Harold J||Thermal processes for subsurface formations|
|US20090159265 *||May 8, 2006||Jun 25, 2009||Rune Freyer||Packer-anchoring device|
|US20100181114 *||Mar 27, 2008||Jul 22, 2010||Bruno Best||Method of interconnecting subterranean boreholes|
|US20130161008 *||Dec 22, 2011||Jun 27, 2013||Argonne National Laboratory||Preparation and use of nano-catalysts for in-situ reaction with kerogen|
|US20150083398 *||Sep 20, 2013||Mar 26, 2015||Statoil Gulf Services LLC||Producing hydrocarbons|
|CN102187054B||Oct 9, 2009||Aug 27, 2014||国际壳牌研究有限公司||Circulated heated transfer fluid heating of subsurface hydrocarbon formations|
|WO2010045097A1 *||Oct 9, 2009||Apr 22, 2010||Shell Oil Company||Circulated heated transfer fluid heating of subsurface hydrocarbon formations|
|U.S. Classification||166/266, 166/271, 166/272.6|
|International Classification||E21B43/40, E21B43/34, E21B43/24, E21B43/16|
|Cooperative Classification||E21B43/2405, E21B43/40|
|European Classification||E21B43/24K, E21B43/40|