EP0069827A2 - Secondary oil recovery system - Google Patents
Secondary oil recovery system Download PDFInfo
- Publication number
- EP0069827A2 EP0069827A2 EP82102741A EP82102741A EP0069827A2 EP 0069827 A2 EP0069827 A2 EP 0069827A2 EP 82102741 A EP82102741 A EP 82102741A EP 82102741 A EP82102741 A EP 82102741A EP 0069827 A2 EP0069827 A2 EP 0069827A2
- Authority
- EP
- European Patent Office
- Prior art keywords
- pump
- steam
- oil recovery
- steam generator
- borehole
- 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.)
- Withdrawn
Links
- 238000011084 recovery Methods 0.000 title claims abstract description 19
- 238000000034 method Methods 0.000 claims abstract description 8
- 230000015572 biosynthetic process Effects 0.000 claims description 15
- 238000005755 formation reaction Methods 0.000 claims description 15
- 238000005086 pumping Methods 0.000 claims description 4
- 238000011065 in-situ storage Methods 0.000 claims description 2
- 238000004519 manufacturing process Methods 0.000 description 4
- 230000006872 improvement Effects 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 238000001816 cooling Methods 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000002708 enhancing effect Effects 0.000 description 1
- 239000000446 fuel Substances 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000000638 stimulation Effects 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Images
Classifications
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK 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
- E21B43/24—Enhanced recovery methods for obtaining hydrocarbons using heat, e.g. steam injection
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B36/00—Heating, cooling or insulating arrangements for boreholes or wells, e.g. for use in permafrost zones
- E21B36/006—Combined heating and pumping means
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B36/00—Heating, cooling or insulating arrangements for boreholes or wells, e.g. for use in permafrost zones
- E21B36/02—Heating, cooling or insulating arrangements for boreholes or wells, e.g. for use in permafrost zones using burners
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK 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
- E21B43/12—Methods or apparatus for controlling the flow of the obtained fluid to or in wells
- E21B43/121—Lifting well fluids
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK 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
- E21B43/14—Obtaining from a multiple-zone well
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
- F04B47/00—Pumps or pumping installations specially adapted for raising fluids from great depths, e.g. well pumps
- F04B47/02—Pumps or pumping installations specially adapted for raising fluids from great depths, e.g. well pumps the driving mechanisms being situated at ground level
Definitions
- This invention relates to secondary oil recovery systems and is particularly directed to means for generating steam within a borehole and recovering oil stimulated by said steam.
- the Wagner device is a vast improvement over previous steam generators. However, there has still been considerable room for further improvement.
- the generator is lowered down the borehole to the level of the formation to be treated, where it generates steam and injects the steam into the formation.
- the steam generator is withdrawn from the borehole and is replaced by a pump which serves to produce the oil which was released by the steam.
- a substantial period of time is required to accomplish this transfer and the steam-treated formation will be cooling down during this period. Consequently, much of the effect of the steam treatment is wasted.
- the operations involved in lowering the steam generator into the borehole, subsequently removing it, and lowering the pump require much labor and downtime, whi-h add substantially to the cost of the process.
- the advantages of the present invention are preferably attained by providing a secondary oil recovery system having a downhole steam generator and pump mounted substantially in parallel with each other so as to permit simultaneous positioning in the borehole and to permit independent operation of the steam generator and pump, so that the pump may be operated sequentially or simultaneously with the steam generator.
- Another object of the present invention is to provide an improved method and apparatus for steam treating subterranian formations and recovering oil released from the formations by the treatment.
- An additional object of the present invention is to provide apparatus for steam treating borehole formations and recovering oil released by the treatment without requiring intermediate transfer of apparatus into and out of the borehole.
- a specific object of the present invention is to provide a secondary oil recovery system comprising a downhole steam generator and a pump secured substantially parallel with each other to permit simultaneous positioning in the borehole and means for operating the pump independently of the steam generator to permit the pump to be operated sequentially or simultaneously with the steam generator.
- FIG. 1 shows a secondary oil recovery system, indicated generally at 2, located in a borehole 4 which penetrates a plurality of formations, as indicated at 6, 8, 10, and 12.
- the borehole 4 may be enclosed by casing 14 along part of its length.
- the formation 10 to be treated must either be increased or, if cased, the casing must be perforated.
- the oil recovery system 2 comprises a steam generator unit 16, which may be similar to that of Wagner et al, cited above.
- a water line 18, a fuel line 20 and an air line 22 connect the steam generator unit 16 with suitable supply sources, not shown, at the surface.
- the output of the steam generator unit 16 is delivered through conduit 24, check valve 26, conduit 28, and exhaust nozzle 30 into the borehole 4 and the formation 10 to be treated.
- a suitable pump 32 is mounted adjacent conduit 28 and is actuated from the surface by suitable means, such as sucker rod 34. The pump 32 draws oil from the borehole 4 through inlet 36 and conduit 38, and delivers the oil to the surface through conduit 40.
- a suitable packer 42 secures conduits 28 and 38 together and serves to maintain the recovery system 2 at a desired location in the borehole 4 and to seal the borehole 4 so as to drive the steam into the formation 10 to be treated.
- Additional coupling means 44 serve to secure the components together to form an integral unit.
- the pump inlet 36 is positioned immediately adjacent the steam nozzle 30.
- This arrangement is preferred for what is called “huff and puff" operation, wherein the steam generator 16 and pump 32 are actuated sequentially.
- the pressure developed by the steam will drive oil out of the borehole 4 and, hence, will preclude simultaneous pumping while the steam generator 16 is operating.
- pump 32 can be actuated in the same instant that the steam generator 16 stops.
- production can be initiated while the formation 10 is at its hottest temperature and the oil is at its lowest viscosity.
- a substantial quantity of oil can be pumped during the time heretofore required for transfer of equipment.
- FIG. 3 shows an oil recovery system 2 which is similar to that of FIG. 1 except that the pump inlet conduit 38 is elongated so as to position the pump inlet 36 a substantial distance below the steam exhaust nozzle 30.
Landscapes
- Engineering & Computer Science (AREA)
- Geology (AREA)
- Life Sciences & Earth Sciences (AREA)
- Mining & Mineral Resources (AREA)
- Environmental & Geological Engineering (AREA)
- Fluid Mechanics (AREA)
- Physics & Mathematics (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Treatment Of Liquids With Adsorbents In General (AREA)
- Engine Equipment That Uses Special Cycles (AREA)
- Production Of Liquid Hydrocarbon Mixture For Refining Petroleum (AREA)
- Cyclones (AREA)
Abstract
A method and apparatus for oil recovery wherein a downhole steam generator 16 and a pump 32 are secured substantially parallel with each other to permit simultaneous positioning in the borehole and are operated independently whereby said pump 32 can be operated sequentially or simultaneously with said generator 16.
Description
- This invention relates to secondary oil recovery systems and is particularly directed to means for generating steam within a borehole and recovering oil stimulated by said steam.
- The use of steam for enhancing secondary oil recovery began in the United States around 1960. Originally, the process called for a steam generator located at the surface with the steam being injected into the treated well. Over the next twenty years, steam stimulation has gained wide acceptance and downhole steam generators have been developed, which are lowered into the borehole to generate steam in situ. Typical of these downhole steam generators is that disclosed in the copending application of William R. Wagner et al, Ser. No. 202,990, filed 11-3-80, assigned to the present assignee.
- The Wagner device is a vast improvement over previous steam generators. However, there has still been considerable room for further improvement. With the steam generators of the Wagner type, the generator is lowered down the borehole to the level of the formation to be treated, where it generates steam and injects the steam into the formation. After a desired period of time, the steam generator is withdrawn from the borehole and is replaced by a pump which serves to produce the oil which was released by the steam. Obviously a substantial period of time is required to accomplish this transfer and the steam-treated formation will be cooling down during this period. Consequently, much of the effect of the steam treatment is wasted. Moreover, the operations involved in lowering the steam generator into the borehole, subsequently removing it, and lowering the pump, require much labor and downtime, whi-h add substantially to the cost of the process.
- These disadvantages of the prior art are overcome with the present invention and a method and apparatus are provided which eliminate the losses associated with equipment transfers and which permit steam treatment and production to occur without intermediate equipment transfers and, in fact, permit production to occur simultaneously with the steam treatment.
- The advantages of the present invention are preferably attained by providing a secondary oil recovery system having a downhole steam generator and pump mounted substantially in parallel with each other so as to permit simultaneous positioning in the borehole and to permit independent operation of the steam generator and pump, so that the pump may be operated sequentially or simultaneously with the steam generator.
- Accordingly, it is an object of the present invention to provide an improved system for secondary oil recovery.
- Another object of the present invention is to provide an improved method and apparatus for steam treating subterranian formations and recovering oil released from the formations by the treatment.
- An additional object of the present invention is to provide apparatus for steam treating borehole formations and recovering oil released by the treatment without requiring intermediate transfer of apparatus into and out of the borehole.
- A specific object of the present invention is to provide a secondary oil recovery system comprising a downhole steam generator and a pump secured substantially parallel with each other to permit simultaneous positioning in the borehole and means for operating the pump independently of the steam generator to permit the pump to be operated sequentially or simultaneously with the steam generator.
- These and other objects and features of the present invention will be apparent from the following detailed description, taken with reference to the accompanying drawing.
- In the drawings:
- FIG. 1 is a diagrammatic representation of a secondary oil recovery system embodying the present invention;
- FIG. 2 is a transverse section through the system of FIG. 1, taken on the line 2 - - 2 thereof; and FIG. 3 is a diagrammatic representation of an alternative form of the oil recovery system of FIG. 1.
- In that form of the present invention chosen for purposes of illustration in the drawing, FIG. 1 shows a secondary oil recovery system, indicated generally at 2, located in a
borehole 4 which penetrates a plurality of formations, as indicated at 6, 8, 10, and 12. If desired, theborehole 4 may be enclosed bycasing 14 along part of its length. Obviously, however, theformation 10 to be treated must either be increased or, if cased, the casing must be perforated. - The
oil recovery system 2 comprises asteam generator unit 16, which may be similar to that of Wagner et al, cited above. Awater line 18, afuel line 20 and anair line 22 connect thesteam generator unit 16 with suitable supply sources, not shown, at the surface. The output of thesteam generator unit 16 is delivered throughconduit 24,check valve 26,conduit 28, andexhaust nozzle 30 into theborehole 4 and theformation 10 to be treated. Asuitable pump 32 is mountedadjacent conduit 28 and is actuated from the surface by suitable means, such assucker rod 34. Thepump 32 draws oil from theborehole 4 throughinlet 36 and conduit 38, and delivers the oil to the surface throughconduit 40. Asuitable packer 42secures conduits recovery system 2 at a desired location in theborehole 4 and to seal theborehole 4 so as to drive the steam into theformation 10 to be treated. Additional coupling means 44 serve to secure the components together to form an integral unit. - As shown, the
pump inlet 36 is positioned immediately adjacent thesteam nozzle 30. This arrangement is preferred for what is called "huff and puff" operation, wherein thesteam generator 16 andpump 32 are actuated sequentially. With this arrangement, the pressure developed by the steam will drive oil out of theborehole 4 and, hence, will preclude simultaneous pumping while thesteam generator 16 is operating. However,pump 32 can be actuated in the same instant that thesteam generator 16 stops. Thus, production can be initiated while theformation 10 is at its hottest temperature and the oil is at its lowest viscosity. Thus, a substantial quantity of oil can be pumped during the time heretofore required for transfer of equipment. Moreover, since no equipment transfer is needed, it becomes feasible to operate thesteam generator 16 andpump 32 on alternating schedules, such as four hours of steam treatment followed by four hours of pumping. - FIG. 3 shows an
oil recovery system 2 which is similar to that of FIG. 1 except that thepump inlet conduit 38 is elongated so as to position the pump inlet 36 a substantial distance below thesteam exhaust nozzle 30. With this arrangement, oil that is released from theformation 10 by the steam treatment will drain into theborehole 4 adjacent thepump inlet 36 with the result thatsteam generator 16 andpump 32 can be operated simultaneously. This permits recovery from extremely difficult formations which would not yield to prior art methods of production. - Obviously, numerous other variations and modification can be made without departing from the present invention. Accordingly, it should be clearly understood that the forms of the present invention described above and shown in the accompanying drawing are illustrative only and are not intended to limit the scope of this invention.
Claims (6)
1. An oil recovery system comprising:
a downhole steam generator;
a pump secured substantially parallel with said steam generator to permit simultaneous positioning of said pump and said generator in a borehole; and
means for operating said pump and said generator independently of each other.
2. The oil recovery system of Claim 1 wherein the intake for said pump is located adjacent to and slightly above the outlet nozzle of said steam generator.
3. The oil recovery system of Claim 1 wherein the intake for said pump is located a substantial distance below the outlet nozzle of said steam generator.
4. The oil recovery system of Claim 1 wherein said means for operating permits simultaneous operation of said pump and said steam generator.
5. The method of oil recovery comprising the steps of:
generating steam in situ at a location within a borehole;
injecting said steam into the formations adjacent said borehole to release oil from said formations; and
pumping said oil to the surface without removing said steam generator.
6. The method of Claim 5 wherein said pumping step is performed simultaneous with said generating step.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US28248881A | 1981-07-13 | 1981-07-13 | |
US282488 | 1988-12-12 |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0069827A2 true EP0069827A2 (en) | 1983-01-19 |
EP0069827A3 EP0069827A3 (en) | 1984-05-16 |
Family
ID=23081728
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP82102741A Withdrawn EP0069827A3 (en) | 1981-07-13 | 1982-03-31 | Secondary oil recovery system |
Country Status (4)
Country | Link |
---|---|
EP (1) | EP0069827A3 (en) |
JP (1) | JPS5811291A (en) |
DK (1) | DK294582A (en) |
NO (1) | NO822104L (en) |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2008045946A1 (en) * | 2006-10-10 | 2008-04-17 | Halliburton Energy Services, Inc. | Producing resources using steam injection |
WO2010019673A1 (en) * | 2008-08-13 | 2010-02-18 | Conocophillips Company | Well completion system |
CN103775046A (en) * | 2013-11-08 | 2014-05-07 | 中国石油天然气股份有限公司 | Thick oil separate injection and joint production eccentric feedback pump and process method |
EP2749955A1 (en) * | 2012-12-27 | 2014-07-02 | Kao Corporation | Liquid Developer |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE3440907C2 (en) * | 1984-11-09 | 1987-01-22 | WAFIOS Maschinenfabrik GmbH & Co KG, 7410 Reutlingen | Method and device for producing oval chain links from round wire |
Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1703428A (en) * | 1926-02-08 | 1929-02-26 | Karl P Neilsen | Well heating and pumping system |
US2980184A (en) * | 1958-09-22 | 1961-04-18 | Shell Oil Co | Method and apparatus for producing wells |
US2998069A (en) * | 1958-03-27 | 1961-08-29 | Raymond M Stephens | Oil well heater |
US3028916A (en) * | 1958-03-27 | 1962-04-10 | Beehler Vernon D | Oil well heating system |
US3420301A (en) * | 1966-12-05 | 1969-01-07 | Louisiana Hydrolec Inc | Apparatus for heating and recovering underground oil |
US4078613A (en) * | 1975-08-07 | 1978-03-14 | World Energy Systems | Downhole recovery system |
US4185691A (en) * | 1977-09-06 | 1980-01-29 | E. Sam Tubin | Secondary oil recovery method and system |
-
1982
- 1982-03-31 EP EP82102741A patent/EP0069827A3/en not_active Withdrawn
- 1982-06-22 JP JP57106282A patent/JPS5811291A/en active Pending
- 1982-06-23 NO NO822104A patent/NO822104L/en unknown
- 1982-06-30 DK DK294582A patent/DK294582A/en not_active Application Discontinuation
Patent Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1703428A (en) * | 1926-02-08 | 1929-02-26 | Karl P Neilsen | Well heating and pumping system |
US2998069A (en) * | 1958-03-27 | 1961-08-29 | Raymond M Stephens | Oil well heater |
US3028916A (en) * | 1958-03-27 | 1962-04-10 | Beehler Vernon D | Oil well heating system |
US2980184A (en) * | 1958-09-22 | 1961-04-18 | Shell Oil Co | Method and apparatus for producing wells |
US3420301A (en) * | 1966-12-05 | 1969-01-07 | Louisiana Hydrolec Inc | Apparatus for heating and recovering underground oil |
US4078613A (en) * | 1975-08-07 | 1978-03-14 | World Energy Systems | Downhole recovery system |
US4185691A (en) * | 1977-09-06 | 1980-01-29 | E. Sam Tubin | Secondary oil recovery method and system |
Cited By (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2008045946A1 (en) * | 2006-10-10 | 2008-04-17 | Halliburton Energy Services, Inc. | Producing resources using steam injection |
US7832482B2 (en) | 2006-10-10 | 2010-11-16 | Halliburton Energy Services, Inc. | Producing resources using steam injection |
WO2010019673A1 (en) * | 2008-08-13 | 2010-02-18 | Conocophillips Company | Well completion system |
CN102124181A (en) * | 2008-08-13 | 2011-07-13 | 科诺科飞利浦公司 | Well completion system |
US8079417B2 (en) | 2008-08-13 | 2011-12-20 | Conocophillips Company | Wireline retrievable dsg/downhole pump system for cyclic steam and continuous steam flooding operations in petroleum reservoirs |
EP2749955A1 (en) * | 2012-12-27 | 2014-07-02 | Kao Corporation | Liquid Developer |
US9098004B2 (en) | 2012-12-27 | 2015-08-04 | Kao Corporation | Liquid developer |
CN103775046A (en) * | 2013-11-08 | 2014-05-07 | 中国石油天然气股份有限公司 | Thick oil separate injection and joint production eccentric feedback pump and process method |
CN103775046B (en) * | 2013-11-08 | 2017-01-11 | 中国石油天然气股份有限公司 | Thick oil separate injection and joint production eccentric feedback pump and process method |
Also Published As
Publication number | Publication date |
---|---|
DK294582A (en) | 1983-01-14 |
JPS5811291A (en) | 1983-01-22 |
EP0069827A3 (en) | 1984-05-16 |
NO822104L (en) | 1983-01-14 |
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Legal Events
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PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
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AK | Designated contracting states |
Designated state(s): BE CH DE FR GB IT LI NL SE |
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PUAL | Search report despatched |
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AK | Designated contracting states |
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17P | Request for examination filed |
Effective date: 19840926 |
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STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN |
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18D | Application deemed to be withdrawn |
Effective date: 19851230 |
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RIN1 | Information on inventor provided before grant (corrected) |
Inventor name: TUTTLE, GARY EDWARD |