WO2007141287A1 - Cyclic steam stimulation method with multiple fractures - Google Patents
Cyclic steam stimulation method with multiple fractures Download PDFInfo
- Publication number
- WO2007141287A1 WO2007141287A1 PCT/EP2007/055550 EP2007055550W WO2007141287A1 WO 2007141287 A1 WO2007141287 A1 WO 2007141287A1 EP 2007055550 W EP2007055550 W EP 2007055550W WO 2007141287 A1 WO2007141287 A1 WO 2007141287A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- steam
- formation
- well
- disk
- viscous hydrocarbon
- Prior art date
Links
- 238000000034 method Methods 0.000 title claims description 28
- 238000010794 Cyclic Steam Stimulation Methods 0.000 title claims description 26
- 208000006670 Multiple fractures Diseases 0.000 title description 2
- 230000015572 biosynthetic process Effects 0.000 claims abstract description 62
- 229930195733 hydrocarbon Natural products 0.000 claims abstract description 30
- 150000002430 hydrocarbons Chemical class 0.000 claims abstract description 30
- 238000010793 Steam injection (oil industry) Methods 0.000 claims abstract description 28
- 238000004519 manufacturing process Methods 0.000 claims abstract description 19
- 239000004215 Carbon black (E152) Substances 0.000 claims abstract description 18
- 238000005520 cutting process Methods 0.000 claims abstract description 11
- 238000005553 drilling Methods 0.000 claims abstract description 3
- 239000003921 oil Substances 0.000 claims description 15
- 238000010795 Steam Flooding Methods 0.000 claims description 5
- 238000010438 heat treatment Methods 0.000 claims description 5
- 238000010924 continuous production Methods 0.000 claims description 4
- 239000012530 fluid Substances 0.000 claims description 3
- 239000000295 fuel oil Substances 0.000 claims description 2
- 238000011065 in-situ storage Methods 0.000 claims description 2
- 230000001788 irregular Effects 0.000 claims description 2
- 125000004122 cyclic group Chemical group 0.000 abstract description 4
- 230000000638 stimulation Effects 0.000 abstract 1
- 206010017076 Fracture Diseases 0.000 description 22
- 208000010392 Bone Fractures Diseases 0.000 description 9
- 239000010779 crude oil Substances 0.000 description 9
- 238000002791 soaking Methods 0.000 description 3
- 238000004364 calculation method Methods 0.000 description 2
- 238000004590 computer program Methods 0.000 description 2
- 238000005094 computer simulation Methods 0.000 description 2
- 239000007924 injection Substances 0.000 description 2
- 238000002347 injection Methods 0.000 description 2
- 238000004088 simulation Methods 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- 208000013201 Stress fracture Diseases 0.000 description 1
- 230000035515 penetration Effects 0.000 description 1
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
- E21B43/24—Enhanced recovery methods for obtaining hydrocarbons using heat, e.g. steam injection
- E21B43/2405—Enhanced recovery methods for obtaining hydrocarbons using heat, e.g. steam injection in association with fracturing or crevice forming processes
-
- 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
- E21B43/24—Enhanced recovery methods for obtaining hydrocarbons using heat, e.g. steam injection
-
- 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
- the invention relates to a cyclic steam stimulation (CSS) method for producing heated hydrocarbons from a viscous hydrocarbon-containing formation.
- Canadian patent 2219513 discloses a cyclic steam stimulation (CSS) process wherein during an initial heating step steam is injected into a viscous hydrocarbon-containing formation through steam injection nozzles that are located at several locations along the length of a substantially horizontal lower section of a well and wherein during a subsequent production step heated hydrocarbons are produced back via the nozzles to the wellhead.
- the steps of steam injection and subsequently producing hydrocarbon are cyclically repeated until a substantial fraction of hydrocarbons has been produced from the formation.
- a common disadvantage of the known CSS methods is that the depth of steam penetration into the formation is limited and that, if fractures are formed, their locations are difficult to control, thereby resulting in an uncontrollable and inefficient heating of the hydrocarbon formation.
- Field experiences also indicate that, at most, only a couple of fractures can be created by the known method, leaving large parts of the formation unheated for an extended period.
- Canadian patent 2219513 proposes using nozzles to regulate and distribute steam injection more uniformly along the well.
- the disadvantage of this method is that the oil production rate from the same well will be significantly lowered by the restricted flow through the nozzles because of the lower mobility of oil relative to the injected steam.
- US patent application US2005/0263284 discloses a method for perforating and fracturing a formation using fluid jets that are located at various longitudinally and circumferentially spaced locations in a liner to initiate microfractures that are oriented in different directions relative to the wellbore.
- CSS novel cyclic steam stimulation
- a cyclic steam stimulation method for producing heated hydrocarbons from a viscous hydrocarbon-containing formation comprising the following steps: a) drilling a well having a substantially horizontal or inclined lower section into the viscous hydrocarbon- containing formation substantially along the trajectory of the minimum compressive horizontal stress Sh; b) cutting at selected intervals along the length of the lower well section substantially disk-shaped cavities into the viscous hydrocarbon-containing formation by a rotating hydraulic jet cutting device; c) completing the well; d) injecting steam into the well and disk-shaped cavities at such an elevated pressure that the hydraulic pressure in at least one disk-shaped cavity is above the formation fracturing pressure, thereby fracturing the formation and permitting the steam to invade the formation surrounding the fracture and to heat hydrocarbons in the steam invaded zone; e) interrupting steam injection and producing heated hydrocarbons via the well; and f) repeating steps (d) and (e) a number of times.
- the well is placed on continuous production whilst steam is injected continuously to a new well drilled near an upper portion of the viscous hydrocarbon-containing formation.
- the rotating hydraulic jet cutting device may comprise at least one jet nozzle which is induced to cut a disk- shaped cavity by ejecting fluid in a substantially orthogonal direction relative to a longitudinal axis of the lower well section whilst rotating the nozzle relative to said longitudinal axis and maintaining the nozzle at a fixed position along the length of said longitudinal axis.
- initial fractures may be created predominantly in the formation surrounding the disk- shaped cavity, where the stress concentration is relatively high due to the irregular geometry of the intersection of the substantially cylindrical well and the substantially disk-shaped cavity and wherein after sufficient steam injection into the initial fractures, the initial fractures cease to open due to the increased horizontal stress resulting from the temperature rises in the adjacent formation, such that during subsequent cycles of steam injection in accordance with step (d) , new fractures are created in the formation surrounding the remaining disk-shaped cavities along the well section .
- the average temperature of the formation may be sufficiently high such that both the minimum (Sh) and maximum (SH) compressive horizontal stresses are greater than the vertical compressive stress (SV) and additional fractures are created in substantially low-angle or horizontal orientations.
- the viscous hydrocarbon formation at its initial state, may have a minimum compressive in-situ principal stress that is oriented in a substantially horizontal direction but may with sufficient temperature rise be reoriented to a substantially vertical direction.
- the viscous hydrocarbon formation may be a heavy-oil reservoir situated from 200 to 3500 meters from the surface with the oil viscosity ranging from 2000 up to 1000000 cp at the reservoir condition and the method according to the invention may be used to create a root shaped pattern of fractures for accelerating steam injection into and oil production from the viscous hydrocarbon-containing formation .
- Figure 1 shows a steam injection and oil production well around which disk-shaped cavities are cut in accordance with the method according to the invention
- Figure 2 shows how during an initial steam soak injection cycle a fracture is created in the formation surrounding a disk-shaped cavity, which is located closest to the wellhead
- Figure 3 shows how during a subsequent steam injection cycle a fracture is created in the formation surrounding a disk-shaped cavity, which is located further away from the wellhead;
- Figure 4 shows how a network of fractures is created in the formation surrounding a plurality of disk-shaped cavities after a plurality of steam soaking cycles
- Figure 5 shows the results of a computer simulation that calculates oil production from a cyclic steam soaked (CSS) well provided with disk-shaped cavities according to the invention and oil production from a prior art CSS well, which is not provided with disk-shaped cavities; and
- CSS cyclic steam soaked
- Figure 6 shows the results of a computer simulation that calculates steam injection rate into a formation surrounding a cyclic steam soaked (CSS) well provided with disk-shaped cavities according to the invention and the stream injection rate into a formation surrounding a prior art CSS well, which is not provided with disk- shaped cavities.
- Figure 1 shows a well 1 with a substantially vertical upper section in which a well casing 2 is arranged and a substantially horizontal lower section 3 which penetrates a viscous oil containing formation 4 in which a series of five disk-shaped cavities 5A-D are being cut by a rotating jet cutting device 6.
- the jet cutting device 6 is supported and rotated by a coiled tubing or drill string assembly 7, such that the rotating jet cutting device 6 is rotated about a longitudinal axis of the wellbore over at least 360 degrees to cut the disk-shaped cavity 5A in the formation surrounding the wellbore.
- Figure 1 also shows that the formation is subject to a three dimensional combination of minimum and maximum horizontal and vertical compressive stresses Sh, SH and Sv and that the trajectory of the lower well section 3 is oriented substantially along the trajectory of minimum compressive horizontal stress Sh.
- Figure 2 shows how steam is injected through a production tubing 7, which is optionally provided with a sandscreen 8 that extends through the horizontal lower section 3 of the well shown in Figure 1, around which a series of six disk-shaped cavities 5A-E have been cut at regular intervals along the length of the horizontal lower section 3.
- the steam is injected at such a high pressure that the formation surrounding the uppermost disk-shaped cavity 5A is fractured such that a first fracture 9 extends substantially radially outward from the uppermost disk-shaped cavity 5A.
- Figure 3 shows how during a subsequent steam injection cycle the first fracture 9 is closed due to increased horizontal stresses Sh and SH resulting from the heating and expansion of the formation surrounding the first fracture 9, whereas a second fracture is created around an intermediate fracture 5C, where the horizontal stresses Sh and SH are not significantly increased as a result of the expansion of the heated formation surrounding the first fracture 5A because of the very low mobility of the viscous crude oil and the low heat transfer through the viscous crude oil containing formation.
- Figure 4 shows how a root-shaped network 12 of principal fractures 9, 10 and branch fractures 11 is created after a series of five or more steam injection and subsequent heated crude oil production cycles, such that five or more cyclic steam soaks (CSS) have been carried out.
- SCS cyclic steam soaks
- Figure 5 shows a calculation of oil production calculated by a reservoir simulation computer program, wherein the upper, solid, curve 50 shows the calculated crude oil production from a CSS well 1 which penetrates a formation in which a series of disk-shaped cavities 5A-5E according to the invention are cut in the manner illustrated in Figures 1 - 4 and the lower, dashed, curve 51 shows the calculated crude oil production from a prior art CSS well, which is not surrounded by disk- shaped cavities.
- the calculated curves illustrate that the crude oil production from a viscous crude oil containing formation is significantly higher by providing disk-shaped cavities 5A-5E around the well 1 in accordance with the invention.
- the points 52 and 53 illustrate that after a series of CSS steam soaking cycles a conventional steam drive may be started where the well 1 is put on continuous production whilst steam is injected continuously via a dedicated steam injection well (not shown) which may be drilled near an upper portion of the viscous oil containing formation, and that crude oil production from the well 1 surrounded by disk- shaped fractures 5A-5E according to the invention is significantly higher than from the conventional prior art well.
- Figure 6 shows a calculation of steam injection rates calculated by a reservoir simulation computer program, wherein the upper, solid, curve 60 shows the calculated steam injection rate into a formation surrounding a CSS well 1 which penetrates a formation in which a series of disk-shaped cavities 5A-5E according to the invention are cut in the manner illustrated in Figures 1 - 4; and the lower, dashed, curve 61 shows the calculated steam injection rate from a prior art CSS well, which is not surrounded by disk-shaped cavities.
- the calculated curves illustrate that the steam injection rate into a viscous crude oil containing formation is significantly higher by providing disk-shaped cavities 5A-5E around the well 1 in accordance with the invention.
- the points 62 and 63 illustrate that after a series of CSS steam soaking cycles a conventional steam drive may be started where the well 1 is put on continuous production whilst steam is injected continuously via a dedicated steam injection well (not shown) which may be drilled near an upper portion of the viscous oil containing formation, and that steam injection into the formation surrounding the well 1 surrounded by disk-shaped fractures 5A-5E according to the invention is significantly higher than from the conventional prior art well.
Abstract
Description
Claims
Priority Applications (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US12/303,621 US8025101B2 (en) | 2006-06-08 | 2007-06-06 | Cyclic steam stimulation method with multiple fractures |
AU2007255397A AU2007255397A1 (en) | 2006-06-08 | 2007-06-06 | Cyclic steam stimulation method with multiple fractures |
BRPI0712230-6A BRPI0712230A2 (en) | 2006-06-08 | 2007-06-06 | cyclic vapor stimulation method for producing heated hydrocarbons from a viscous hydrocarbon-containing formation |
CA002654049A CA2654049A1 (en) | 2006-06-08 | 2007-06-06 | Cyclic steam stimulation method with multiple fractures |
GB0821096A GB2451601A (en) | 2006-06-08 | 2008-11-18 | Cyclic steam stimulation method with multiple fractures |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP06115127 | 2006-06-08 | ||
EP06115127.0 | 2006-06-08 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2007141287A1 true WO2007141287A1 (en) | 2007-12-13 |
Family
ID=37192293
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/EP2007/055550 WO2007141287A1 (en) | 2006-06-08 | 2007-06-06 | Cyclic steam stimulation method with multiple fractures |
Country Status (7)
Country | Link |
---|---|
US (1) | US8025101B2 (en) |
CN (1) | CN101460702A (en) |
AU (1) | AU2007255397A1 (en) |
BR (1) | BRPI0712230A2 (en) |
CA (1) | CA2654049A1 (en) |
GB (1) | GB2451601A (en) |
WO (1) | WO2007141287A1 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN104832145A (en) * | 2014-02-07 | 2015-08-12 | 中国石油化工股份有限公司 | Method of improving ultra-deep low-permeability heavy oil steam injection efficiency through fracturing |
Families Citing this family (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US8126689B2 (en) * | 2003-12-04 | 2012-02-28 | Halliburton Energy Services, Inc. | Methods for geomechanical fracture modeling |
CA2820740A1 (en) * | 2012-06-29 | 2013-12-29 | Nexen Inc. | Uplifted single well steam assisted gravity drainage system and process |
US9045978B2 (en) * | 2012-07-10 | 2015-06-02 | Argosy Technologies | Method of increasing productivity of oil, gas, and water wells |
US10526890B2 (en) | 2014-12-19 | 2020-01-07 | Schlumberger Technology Corporation | Workflows to address localized stress regime heterogeneity to enable hydraulic fracturing |
CN105041282B (en) * | 2015-08-17 | 2018-07-17 | 中国石油大学(华东) | Hypotonic horizontal wells in heavy oil reservoir staged fracturing cyclic steam stimulation method in one kind |
US10815776B2 (en) | 2015-09-18 | 2020-10-27 | Schlumberger Technology Corporation | Systems and methods for performing hydraulic fracturing in vertically heterogenous regions |
CN106285570A (en) * | 2016-09-12 | 2017-01-04 | 中国石油天然气股份有限公司 | The recovery method of oil well |
CN106761630B (en) * | 2016-12-26 | 2018-12-25 | 中国石油天然气股份有限公司 | Reservoir heating, recovery method and device |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3421583A (en) * | 1967-08-30 | 1969-01-14 | Mobil Oil Corp | Recovering oil by cyclic steam injection combined with hot water drive |
US5085276A (en) * | 1990-08-29 | 1992-02-04 | Chevron Research And Technology Company | Production of oil from low permeability formations by sequential steam fracturing |
US5305829A (en) * | 1992-09-25 | 1994-04-26 | Chevron Research And Technology Company | Oil production from diatomite formations by fracture steamdrive |
EP0644316A2 (en) * | 1993-09-09 | 1995-03-22 | Halliburton Company | Formation fracturing method |
US20050263284A1 (en) * | 2004-05-28 | 2005-12-01 | Justus Donald M | Hydrajet perforation and fracturing tool |
Family Cites Families (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5957202A (en) * | 1997-03-13 | 1999-09-28 | Texaco Inc. | Combination production of shallow heavy crude |
CA2219513C (en) | 1997-11-18 | 2003-06-10 | Russell Bacon | Steam distribution and production of hydrocarbons in a horizontal well |
US6257334B1 (en) * | 1999-07-22 | 2001-07-10 | Alberta Oil Sands Technology And Research Authority | Steam-assisted gravity drainage heavy oil recovery process |
US6679326B2 (en) * | 2002-01-15 | 2004-01-20 | Bohdan Zakiewicz | Pro-ecological mining system |
CA2543963C (en) * | 2003-11-03 | 2012-09-11 | Exxonmobil Upstream Research Company | Hydrocarbon recovery from impermeable oil shales |
US7228908B2 (en) * | 2004-12-02 | 2007-06-12 | Halliburton Energy Services, Inc. | Hydrocarbon sweep into horizontal transverse fractured wells |
US20070199697A1 (en) * | 2006-02-27 | 2007-08-30 | Grant Hocking | Enhanced hydrocarbon recovery by steam injection of oil sand formations |
-
2007
- 2007-06-06 CA CA002654049A patent/CA2654049A1/en not_active Abandoned
- 2007-06-06 CN CNA2007800210084A patent/CN101460702A/en active Pending
- 2007-06-06 AU AU2007255397A patent/AU2007255397A1/en not_active Abandoned
- 2007-06-06 WO PCT/EP2007/055550 patent/WO2007141287A1/en active Application Filing
- 2007-06-06 BR BRPI0712230-6A patent/BRPI0712230A2/en not_active Application Discontinuation
- 2007-06-06 US US12/303,621 patent/US8025101B2/en not_active Expired - Fee Related
-
2008
- 2008-11-18 GB GB0821096A patent/GB2451601A/en not_active Withdrawn
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3421583A (en) * | 1967-08-30 | 1969-01-14 | Mobil Oil Corp | Recovering oil by cyclic steam injection combined with hot water drive |
US5085276A (en) * | 1990-08-29 | 1992-02-04 | Chevron Research And Technology Company | Production of oil from low permeability formations by sequential steam fracturing |
US5305829A (en) * | 1992-09-25 | 1994-04-26 | Chevron Research And Technology Company | Oil production from diatomite formations by fracture steamdrive |
EP0644316A2 (en) * | 1993-09-09 | 1995-03-22 | Halliburton Company | Formation fracturing method |
US20050263284A1 (en) * | 2004-05-28 | 2005-12-01 | Justus Donald M | Hydrajet perforation and fracturing tool |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN104832145A (en) * | 2014-02-07 | 2015-08-12 | 中国石油化工股份有限公司 | Method of improving ultra-deep low-permeability heavy oil steam injection efficiency through fracturing |
Also Published As
Publication number | Publication date |
---|---|
CA2654049A1 (en) | 2007-12-13 |
US8025101B2 (en) | 2011-09-27 |
BRPI0712230A2 (en) | 2012-01-10 |
AU2007255397A1 (en) | 2007-12-13 |
CN101460702A (en) | 2009-06-17 |
US20100101790A1 (en) | 2010-04-29 |
GB2451601A (en) | 2009-02-04 |
GB0821096D0 (en) | 2008-12-24 |
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