US3120265A - Producing petroleum from a subsurface formation - Google Patents

Producing petroleum from a subsurface formation Download PDF

Info

Publication number
US3120265A
US3120265A US746284A US74628458A US3120265A US 3120265 A US3120265 A US 3120265A US 746284 A US746284 A US 746284A US 74628458 A US74628458 A US 74628458A US 3120265 A US3120265 A US 3120265A
Authority
US
United States
Prior art keywords
formation
petroleum
well bore
gas
producing
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US746284A
Inventor
Joseph C Allen
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Texaco Inc
Original Assignee
Texaco Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Texaco Inc filed Critical Texaco Inc
Priority to US746284A priority Critical patent/US3120265A/en
Application granted granted Critical
Publication of US3120265A publication Critical patent/US3120265A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • E—FIXED CONSTRUCTIONS
    • E21—EARTH DRILLING; MINING
    • E21B—EARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B43/00—Methods or apparatus for obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells
    • E21B43/16—Enhanced recovery methods for obtaining hydrocarbons
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH DRILLING; MINING
    • E21B—EARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B43/00—Methods or apparatus for obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells
    • E21B43/25—Methods for stimulating production
    • E21B43/26—Methods for stimulating production by forming crevices or fractures

Definitions

  • This invention relates to the recovery and production of petroleum from a subsurface petroleum-producing formation.
  • this invention relates to the recovery and production of petroleum from a subsurface petroleum-containing formation employing an operation wherein a well bore is employed both as a gas injection well and as a petroleum production well.
  • lt is an object of this invention to provide an improved method for the recovery and production of petroleum from a subsurface petroleum-producing formation.
  • Another object of this invention is to provide an improved method of recovering and producing petroleum from a subsurface petroleum-producing formation involving operations wherein the same well bore penetrating the petroleum-producing formation is employed as a gas injection well and as a petroleum production well.
  • Another object of this invention is to provide a method wherein a petroleum-producing formation can be produced by the injection of gas into the upper portion thereof while petroleum is being produced from the lower portion thereof, and wherein premature lingering or short circuiting of the injected gas from the upper portion of the formation into the lower portion of the formation in the vicinity of the well bore during the petroleum production operation is inhibited or obviated.
  • Yet another object of this invention is to provide a method for the production of petroleum from subsurface petroleum-producing formations having relatively little structural relief or dip.
  • Still another object of this invention is to provide a method of producing petroleum from subsurface petroleum-producing formations involving operations wherein advantage is taken of the segregating effect of gravity,
  • an improved method of recovering and producing petroleum from a subsurface petroleum-containing formation is accomplished by creating a water block, i.e., a water permeable, substantially gas or hydrocarbon impermeable zone, in the upper portion of the petroleum-producing formation in the vicinity of the Well bore, followed by the injection of gas into the upper portion of the formation at a location above the aforesaid gas or hydrocarbon impermeable Zone and producing petroleum from the lower portion of the formation beneath the aforesaid gas or hydrocarbon impermeable zone.
  • a water block i.e., a water permeable, substantially gas or hydrocarbon impermeable zone
  • Various methods may be employed in the practice of this invention for the creation of a water permeable and gas or hydrocarbon impermeable zone in the upper portion of the formation prior to the injection of gas into the formation above said zone.
  • One method particularly suitable for use in the practice of this invention involves fracturing the petroleum-producing formation in the upper portion thereof to create a substantially horizontal fracture, such as a fracture extending substantially horizontally, radially outwardly from the well bore.
  • the resulting fracture is then treated by the injection of water or aqueous solution thereinto to form a water block therein and within the immediately surrounding formation with the result that the fracture and that portion of the formation inmediately encompassing the fracture are rendered substantially gas or hydrocarbon impermeable.
  • the petroleum-producing formation is fractured in the upper portion thereof by employing as the fracturing fluid an aqueous liquid such as water, brine or an aqueous oil suspension, such as a suspension of oil in water.
  • an aqueous liquid such as water, brine or an aqueous oil suspension, such as a suspension of oil in water.
  • any gas may be suitably employed as a pressuring gas in the practice of this invention.
  • the gas injected into the petroleum-producing formation, above the fluid or gas impermeable Zone created therein, is natural gas, preferably gas recovered from the formation undergoing treatment.
  • Natural gas comprises a major amount of methane and minor amounts of ethane, propane and butane. Accordingly, any of the aforesaid normally gaseous hydrocarbons, alone or in any suitable admixture, may be suitably employed in the practice of this invention as the pressuring gas.
  • Other suitable pressuring gases include flue gas, carbon dioxide, carbon monoxide, air, nitrogen, etc.
  • the substantially liquid hydrocarbon and gas impermeable zone created within the upper portion of the petroleum-producing formation extends substantially horizontally, outwardly, radially from the well bore for a considerable distance, such as a distance in the range lil-260 feet, more or less.
  • the outer periphery of the gas impermeable zone created within the upper portion of the petroleum-producing formation is suiciently removed from the well bore and the lower portion of the formation wherefrom petroleum is produced so that the buoyancy effect, exerted upon the gas injected into the upper portion of the formation, due to the density difference between the gas and the denser liquid petroleum therein, is at least as great as or greater than the pressure differential, exerted upon an increment of gas at the outer periphery of the zone, resulting from the ilow of petroleum into the well bore in the lower portion of the formation during the petroleum-producing operation.
  • th injected gas which reaches the outer periphery of the zone will not be drawn downward directly but will occupy the upper portion of the formation and descend in blanket-like fashion to displace petroleum into the lower portion of the formation.
  • a well bore 11 is shown penetrating petroleum-producing formation 12.
  • the well bore is provided with casing 14.
  • a fracture extending substantially horizontally and radially outwardly from well bore 11 is created within the petroleum-producing formation 12 in the upper portion thereof.
  • a water block formed by the injection of water into fracture 15 and the encompassing formation, in the form of al pancake-shape water permeable, gas impermeable zone s'urroundstwell bore 11. The outline of the water block i's indicated by dashed line 17.
  • Y There is provided within the well bore 11, substantially concentric with respect to casing 14 therein, production tubing 16.
  • production tubing 16 In the annular space between production tubing 16 and casing 14, above fracture 15 and water block 17, there is positioned a packer 18 made of suitable expansible material.
  • the packer 1S serves to make a fluid tight seal between casing 14 and production tubing 16.
  • natural gas, methane supplied from a suitable source at the surface via conduit 19 is injected into Vthe annular space between casing 14 and tubing 16.
  • the thus-injected gas flows down the Yannulus between casing 14 andV tubing 16 and outwardly into the upper portion of petroleum-producing formation 12 via perforations 20 at a location above fracture 15 and water block 17.
  • the gas impermeable 4 zone or water block 17 within the upper portion of the formation 12 prevents any short circuiting or by-passing of the injected gas downwardly along well bore 11 in the direction of production perforations 21.
  • One or more of the aforesaid operations may be carried out consecutively with respect to the same well bore. For example, when it is found thatr the injected gas is entering production perforations 21 in excessive amounts gas injection into formation 12 via perforations 20 may be halted and the formation again treated or fractured and a gas impermeable zone created therein in the zone of the formation adjacent perforations 21, just below these perforations. Gas injection is then resumed into the formation 12 via perforations 2i) and petroleum production resumed from an even lower portion of formation 12 via other perforations, not illustrated. Further, if desired or required, water or an aqueous solution may be injected intermittenly or continuously into Water block 17'to maintain or enlarge its dimensions and to maintain its gas impermeability.
  • a method of producing petroleum via a well bore penetrating a subsurface petroleum-producing formation which comprises fracturing the upper part of said formation to create therein a substantially radial fracture extending outwardly from said well bore, injecting water into said fracture to form and maintain a substantially continuous water block therein so as to create a substantially gas impermeable zone encompassing said fracture within said formation thereby dividing said formation adjacent said well bore into'an upper portion and a lower portion, packing said well bore above and adjacent said zone and below the top of said formation thereby dividing said well bore into an upper portion and a lower portion, introducing a non-oxidizing gas under pressure via said upper portion of said well bore anterioro said upper portion of said formation above said gas impermeable zone, and producing petroleum via tubing extending through packing means in said well bore and into said lower portion of said well bore from said lower portion of said formation beneath said gas impermeable zone.

Description

Feb. 4, 1964 J. C. ALLEN PRODUCING PETROLEUM FROM A SUBSURFACE FORMATION Filed July 2, 1958 arma/7a ,/2
United States Patent O 3,i2i),265 PRODUCENG lEl-.LEUM FROM A SUBSURFAQE FORMAHOH Joseph C. Allen, Bellaire, Tern, assigner to Texaco inc., a corporation of Beiaware File duly 2, H53, Ser. No. 746,234 2 Clmrns. (Cl. lee-42) This invention relates to the recovery and production of petroleum from a subsurface petroleum-producing formation. In accordance with one embodiment this invention relates to the recovery and production of petroleum from a subsurface petroleum-containing formation employing an operation wherein a well bore is employed both as a gas injection well and as a petroleum production well.
One of the most efficient methods of displacing petroleum from a subsurface petroleum-producing formation, particularly a formation having considerable structural relief, is the injection of gas high in the formation, near the top or crest, and producing oil from near the bottom of the formation or lower portion thereof. By operating in this fashion advantage is taken of the natural segregating effect of gravity. There are many formations, however, which possess relatively little structural relief or dip. In the production of petroleum from such formations by injection of gas into the upper portion thereof a multitude of injection wells is required so that the injected gas is forced evenly downwardly, in a blanket-like manner, into the petroleum-producing formation while producing petroleum from the lower portions thereof so that during the gas injection and petroleum production operations advantage may be taken of the segregating effect of gravity. As indicated, however, this method involves the employment of very many wells and, consequently, in most instances is economically prohibitive.
lt is an object of this invention to provide an improved method for the recovery and production of petroleum from a subsurface petroleum-producing formation.
Another object of this invention is to provide an improved method of recovering and producing petroleum from a subsurface petroleum-producing formation involving operations wherein the same well bore penetrating the petroleum-producing formation is employed as a gas injection well and as a petroleum production well.
Another object of this invention is to provide a method wherein a petroleum-producing formation can be produced by the injection of gas into the upper portion thereof while petroleum is being produced from the lower portion thereof, and wherein premature lingering or short circuiting of the injected gas from the upper portion of the formation into the lower portion of the formation in the vicinity of the well bore during the petroleum production operation is inhibited or obviated.
Yet another object of this invention is to provide a method for the production of petroleum from subsurface petroleum-producing formations having relatively little structural relief or dip.
Still another object of this invention is to provide a method of producing petroleum from subsurface petroleum-producing formations involving operations wherein advantage is taken of the segregating effect of gravity,
How these and other objects of this invention are accomplished will become apparent in the light of the accompanying disclosure and drawing wherein there is schematically illustrated a petroleum production operation carried out in accordance with the practice of this invention. In at least one embodiment of the practice of this invention at least one of the foregoing objects will be achieved.
In accordance with this invention an improved method of recovering and producing petroleum from a subsurface petroleum-containing formation is accomplished by creating a water block, i.e., a water permeable, substantially gas or hydrocarbon impermeable zone, in the upper portion of the petroleum-producing formation in the vicinity of the Well bore, followed by the injection of gas into the upper portion of the formation at a location above the aforesaid gas or hydrocarbon impermeable Zone and producing petroleum from the lower portion of the formation beneath the aforesaid gas or hydrocarbon impermeable zone. A
Various methods may be employed in the practice of this invention for the creation of a water permeable and gas or hydrocarbon impermeable zone in the upper portion of the formation prior to the injection of gas into the formation above said zone. One method particularly suitable for use in the practice of this invention involves fracturing the petroleum-producing formation in the upper portion thereof to create a substantially horizontal fracture, such as a fracture extending substantially horizontally, radially outwardly from the well bore. The resulting fracture is then treated by the injection of water or aqueous solution thereinto to form a water block therein and within the immediately surrounding formation with the result that the fracture and that portion of the formation inmediately encompassing the fracture are rendered substantially gas or hydrocarbon impermeable. Desirably in accordnace with one embodiment of the practice of this invention the petroleum-producing formation is fractured in the upper portion thereof by employing as the fracturing fluid an aqueous liquid such as water, brine or an aqueous oil suspension, such as a suspension of oil in water. When a fracturing operation is carried out while employing an aqueous fracturing uid the fracture and water block encompassing the fracture are created substantially at the same time with the result that after the fracturing operation is completed the fracture and that portion of the formation encompassing the fracture are rendered substantially gas or hydrocarbon (oil) impermeable. Other methods of creating a substantially gas or hydrocarbon impermeable water block or similar removable barrier within a petroleum-producing formation are known.
Any gas may be suitably employed as a pressuring gas in the practice of this invention. Desirably, however, the gas injected into the petroleum-producing formation, above the fluid or gas impermeable Zone created therein, is natural gas, preferably gas recovered from the formation undergoing treatment. Natural gas comprises a major amount of methane and minor amounts of ethane, propane and butane. Accordingly, any of the aforesaid normally gaseous hydrocarbons, alone or in any suitable admixture, may be suitably employed in the practice of this invention as the pressuring gas. Other suitable pressuring gases include flue gas, carbon dioxide, carbon monoxide, air, nitrogen, etc.
The substantially liquid hydrocarbon and gas impermeable zone created within the upper portion of the petroleum-producing formation extends substantially horizontally, outwardly, radially from the well bore for a considerable distance, such as a distance in the range lil-260 feet, more or less. Preferably the outer periphery of the gas impermeable zone created within the upper portion of the petroleum-producing formation is suiciently removed from the well bore and the lower portion of the formation wherefrom petroleum is produced so that the buoyancy effect, exerted upon the gas injected into the upper portion of the formation, due to the density difference between the gas and the denser liquid petroleum therein, is at least as great as or greater than the pressure differential, exerted upon an increment of gas at the outer periphery of the zone, resulting from the ilow of petroleum into the well bore in the lower portion of the formation during the petroleum-producing operation. In other words, th injected gas which reaches the outer periphery of the zone will not be drawn downward directly but will occupy the upper portion of the formation and descend in blanket-like fashion to displace petroleum into the lower portion of the formation.
Referring uow'in detail to the accompanying drawing which. schematically illustrates an embodiment of the practice of this invention wherein natural gas is injected into the upper portion of the formation while petroleum is produced from the lower portion of the formation, the gas being injected into and the petroleum being produced via the same well bore, a well bore 11 is shown penetrating petroleum-producing formation 12. The well bore is provided with casing 14. In accordance with this invention, as illustrated in the drawing, a fracture extending substantially horizontally and radially outwardly from well bore 11 is created within the petroleum-producing formation 12 in the upper portion thereof. A water block, formed by the injection of water into fracture 15 and the encompassing formation, in the form of al pancake-shape water permeable, gas impermeable zone s'urroundstwell bore 11. The outline of the water block i's indicated by dashed line 17.
Y There is provided within the well bore 11, substantially concentric with respect to casing 14 therein, production tubing 16. In the annular space between production tubing 16 and casing 14, above fracture 15 and water block 17, there is positioned a packer 18 made of suitable expansible material. The packer 1S serves to make a fluid tight seal between casing 14 and production tubing 16. Following the setting of packer 18 natural gas, methane, supplied from a suitable source at the surface via conduit 19 is injected into Vthe annular space between casing 14 and tubing 16. The thus-injected gas flows down the Yannulus between casing 14 andV tubing 16 and outwardly into the upper portion of petroleum-producing formation 12 via perforations 20 at a location above fracture 15 and water block 17. As the gas is injected into the upper portion of the formation above the gas impermeable zone or water block 177,V or subsequently thereto, petroleum is produced continuously or intermittently from the lower portion of Vformation 12 via perforations 21 provided in the lower end of casing (14. The resulting produced petroleum moves upwardly within production tubing 16Yand is produced at the surface via conduit 22.
In accordance with the foregoing operations injected.
tends to follow the contour lines within the producing formation 12 and migrates in a blanket-like manner downwardly within formation 12 displacing the hydrocarbons. It is to be noted also that the gas impermeable 4 zone or water block 17 within the upper portion of the formation 12 prevents any short circuiting or by-passing of the injected gas downwardly along well bore 11 in the direction of production perforations 21.
One or more of the aforesaid operations may be carried out consecutively with respect to the same well bore. For example, when it is found thatr the injected gas is entering production perforations 21 in excessive amounts gas injection into formation 12 via perforations 20 may be halted and the formation again treated or fractured and a gas impermeable zone created therein in the zone of the formation adjacent perforations 21, just below these perforations. Gas injection is then resumed into the formation 12 via perforations 2i) and petroleum production resumed from an even lower portion of formation 12 via other perforations, not illustrated. Further, if desired or required, water or an aqueous solution may be injected intermittenly or continuously into Water block 17'to maintain or enlarge its dimensions and to maintain its gas impermeability.
As will be apparent to those skilled in the art many alterations, modifications and changes may be made in the practice of this invention in the light of the accompanying disclosure without departing from the spirit or scope of this invention.
I claim:
1. A method of producing petroleum via a well bore penetrating a subsurface petroleum-producing formation which comprises fracturing the upper part of said formation to create therein a substantially radial fracture extending outwardly from said well bore, injecting water into said fracture to form and maintain a substantially continuous water block therein so as to create a substantially gas impermeable zone encompassing said fracture within said formation thereby dividing said formation adjacent said well bore into'an upper portion and a lower portion, packing said well bore above and adjacent said zone and below the top of said formation thereby dividing said well bore into an upper portion and a lower portion, introducing a non-oxidizing gas under pressure via said upper portion of said well bore irito said upper portion of said formation above said gas impermeable zone, and producing petroleum via tubing extending through packing means in said well bore and into said lower portion of said well bore from said lower portion of said formation beneath said gas impermeable zone.
2. A method in accordance withrclairn 1 wherein said formation is fractured by means of an aqueous liquid whereby said formation is simultaneously fractured and the resulting fracture substantially simultaneously treated to form a water block therein.
References Cited in the le of this patent UNITED STATES PATENTS 2,368,424 Reistle Jan. 30, 1945 2,593,497 Spearow Apr. 22, 1952 2,749,988 West June 12, 1956V 2,767,792 Spearow Oct. 23, 1956 2,874,777 Tadema Feb. 24, 1959

Claims (1)

1. A METHOD OF PRODUCING PETROLEUM VIA A WELL BORE PENETRATING A SUBSURFAE PETROLEUM-PRODUCING FORMATION WHICH COMPRISES FRACTURING THE UPPER PART OF SAID FORMATION TO CREATE THEREIN A SUBSTANTIALLY RADIAL FRACTURE EXTENDING OUTWRDLY FROM SAID WELL BORE, INJECTING WATR INTO SAID FRACTURE TO FORM AND MAINTAIN A SUBSTANTIALLY CONTINUOUS WATER BLOCK THEREIN SO AS TO CREATE A SUBSTANTIALLY GAS IMPERMEABLE ZONE ENCOMPASSING SAID FRACTURE WITHIN SAID FORMATION THEREBY DIVIDING SAID FORMATION ADJACENT SAID WELL BORE INTO AN UPPER PORTION AND A LOER PORTION, PACKING ASAID WELL BORE ABOVE AND ADJACENT SAID ZONE AND BELOW TH ETOP OF SAID FORMATION THERBY DIVIDING SAIAD WELL BORE INTO AN UPPER PORITON AND A LOWER PORTION, INTRODUCING A NON-OXIDIZING GAS UNDER PRESSURE VIA SAID UPPER PORTION OF SAID WELL BORE INTO SAID UPPER PORTION OF SAID FORMATION ABOVE SAID GAS IMPERMEABLE ZONE, AND PRODUCING PETROLEUM VIA TUBING EXTENDING THROUGH PACKING MEANS IN SAID WELL BORE AND INTO SAID
US746284A 1958-07-02 1958-07-02 Producing petroleum from a subsurface formation Expired - Lifetime US3120265A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US746284A US3120265A (en) 1958-07-02 1958-07-02 Producing petroleum from a subsurface formation

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US746284A US3120265A (en) 1958-07-02 1958-07-02 Producing petroleum from a subsurface formation

Publications (1)

Publication Number Publication Date
US3120265A true US3120265A (en) 1964-02-04

Family

ID=25000197

Family Applications (1)

Application Number Title Priority Date Filing Date
US746284A Expired - Lifetime US3120265A (en) 1958-07-02 1958-07-02 Producing petroleum from a subsurface formation

Country Status (1)

Country Link
US (1) US3120265A (en)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3228470A (en) * 1962-12-31 1966-01-11 Gulf Research Development Co Method of mitigating the production of undesirable gas or water in oil wells
US3292703A (en) * 1963-09-30 1966-12-20 Exxon Production Research Co Method for oil production and gas injection
US3770057A (en) * 1972-02-14 1973-11-06 Texaco Inc Continuous attic flooding
US4042029A (en) * 1975-04-25 1977-08-16 Shell Oil Company Carbon-dioxide-assisted production from extensively fractured reservoirs
US5025863A (en) * 1990-06-11 1991-06-25 Marathon Oil Company Enhanced liquid hydrocarbon recovery process
WO1998050677A1 (en) * 1997-05-08 1998-11-12 Chenglin Wu A gas-lift ball control device in gas-lift ball oil recovery and a method of oil recovery

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2368424A (en) * 1939-04-15 1945-01-30 Standard Oil Dev Co Producing oil
US2593497A (en) * 1947-05-26 1952-04-22 Spearow Ralph Method and apparatus for producing oil wells
US2749988A (en) * 1952-04-09 1956-06-12 Thomas S West Gravel pack well completion method
US2767792A (en) * 1953-06-10 1956-10-23 Spearow Ralph Multiple horizon oil production method
US2874777A (en) * 1954-07-19 1959-02-24 Shell Dev Producing petroleum by underground combustion

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2368424A (en) * 1939-04-15 1945-01-30 Standard Oil Dev Co Producing oil
US2593497A (en) * 1947-05-26 1952-04-22 Spearow Ralph Method and apparatus for producing oil wells
US2749988A (en) * 1952-04-09 1956-06-12 Thomas S West Gravel pack well completion method
US2767792A (en) * 1953-06-10 1956-10-23 Spearow Ralph Multiple horizon oil production method
US2874777A (en) * 1954-07-19 1959-02-24 Shell Dev Producing petroleum by underground combustion

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3228470A (en) * 1962-12-31 1966-01-11 Gulf Research Development Co Method of mitigating the production of undesirable gas or water in oil wells
US3292703A (en) * 1963-09-30 1966-12-20 Exxon Production Research Co Method for oil production and gas injection
US3770057A (en) * 1972-02-14 1973-11-06 Texaco Inc Continuous attic flooding
US4042029A (en) * 1975-04-25 1977-08-16 Shell Oil Company Carbon-dioxide-assisted production from extensively fractured reservoirs
US5025863A (en) * 1990-06-11 1991-06-25 Marathon Oil Company Enhanced liquid hydrocarbon recovery process
WO1998050677A1 (en) * 1997-05-08 1998-11-12 Chenglin Wu A gas-lift ball control device in gas-lift ball oil recovery and a method of oil recovery
US6293340B1 (en) 1997-05-08 2001-09-25 Chenglin Wu Gas-lift-ball control device and oil producing method using said device

Similar Documents

Publication Publication Date Title
US3004594A (en) Process for producing oil
US2885002A (en) Recovering oil after secondary recovery
US3051235A (en) Recovery of petroleum crude oil, by in situ combustion and in situ hydrogenation
US3120264A (en) Recovery of oil by in situ combustion
US3116792A (en) In situ combustion process
US2910123A (en) Method of recovering petroleum
US2946382A (en) Process for recovering hydrocarbons from underground formations
US3208519A (en) Combined in situ combustion-water injection oil recovery process
US3734184A (en) Method of in situ coal gasification
US4387770A (en) Process for selective injection into a subterranean formation
US3055423A (en) Controlling selective plugging of carbonaceous strata for controlled production of thermal drive
US4042029A (en) Carbon-dioxide-assisted production from extensively fractured reservoirs
US3004596A (en) Process for recovery of hydrocarbons by in situ combustion
US3319712A (en) Secondary oil recovery method
US3261400A (en) Selective plugging method
US5255740A (en) Secondary recovery process
US3266569A (en) Recovery of viscous unsaturated crude by intermittent gas injection
US3246693A (en) Secondary recovery of viscous crude oil
US3010707A (en) Recovery of resins and hydrocarbons from resinous type coals
US3120265A (en) Producing petroleum from a subsurface formation
US3145772A (en) Temperature controlled in-situ combustion process
US3285336A (en) Method of thermal stimulation of oil fields
US3464492A (en) Method for recovery of petroleum oil from confining structures
US3120263A (en) Producing petroleum from a subsurface formation
US3118499A (en) Secondary recovery procedure