WO1992007919A1 - Additive for a drilling fluid - Google Patents
Additive for a drilling fluid Download PDFInfo
- Publication number
- WO1992007919A1 WO1992007919A1 PCT/GB1991/001944 GB9101944W WO9207919A1 WO 1992007919 A1 WO1992007919 A1 WO 1992007919A1 GB 9101944 W GB9101944 W GB 9101944W WO 9207919 A1 WO9207919 A1 WO 9207919A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- drilling fluid
- additive
- additive according
- drilling
- oxide
- Prior art date
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C09K8/00—Compositions for drilling of boreholes or wells; Compositions for treating boreholes or wells, e.g. for completion or for remedial operations
- C09K8/60—Compositions for stimulating production by acting on the underground formation
- C09K8/84—Compositions based on water or polar solvents
- C09K8/86—Compositions based on water or polar solvents containing organic compounds
- C09K8/88—Compositions based on water or polar solvents containing organic compounds macromolecular compounds
- C09K8/885—Compositions based on water or polar solvents containing organic compounds macromolecular compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C09K8/00—Compositions for drilling of boreholes or wells; Compositions for treating boreholes or wells, e.g. for completion or for remedial operations
- C09K8/02—Well-drilling compositions
- C09K8/04—Aqueous well-drilling compositions
- C09K8/14—Clay-containing compositions
- C09K8/18—Clay-containing compositions characterised by the organic compounds
- C09K8/22—Synthetic organic compounds
- C09K8/24—Polymers
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C09K8/00—Compositions for drilling of boreholes or wells; Compositions for treating boreholes or wells, e.g. for completion or for remedial operations
- C09K8/50—Compositions for plastering borehole walls, i.e. compositions for temporary consolidation of borehole walls
- C09K8/504—Compositions based on water or polar solvents
- C09K8/506—Compositions based on water or polar solvents containing organic compounds
- C09K8/508—Compositions based on water or polar solvents containing organic compounds macromolecular compounds
- C09K8/5086—Compositions based on water or polar solvents containing organic compounds macromolecular compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
Definitions
- This invention relates to additives for drilling fluids.
- Drilling fluids are circulated down the wellbore being drilled during well drilling operations.
- the fluid is usually pumped down the inside of the drillpipe and then passes through the drill bit into the wellbore.
- the fluid returns to the surface through the annulus defined between the exterior of the drillpipe and the wellbore. The fluid is then recovered, processed and reused.
- Drilling fluids are desirable in order to lubricate the drill bit, to cool the drill bit, and to remove rock cuttings generated.
- the physical properties of the drilling fluid can be modified as necessary.
- oil based drilling fluids which are usually formulated with mineral oils. Although these fluids generally contain water, it is tightly emulsified using powerful surfactants. Such fluids are substantially inert to hydratable rocks.
- Another solution to the problem involves the use of water based drilling fluids which incorporate additives having surface active properties; such additives are sorbed onto the rock, reducing the access of water, and thereby reducing the rate of hydration.
- Anionic, cationic and nonionic materials are used, because difference parts of a rock structure shew different affinities to different ionic charges.
- Examples of known additives for reducing hydration include: potassium chloride, partially hydrolysed polyacrylamides (PHPA); gilsonite; polyglycerols; carboxymethylcellulose derivatives, such as polyanionic cellulose; calcium chloride; and sodium silicate.
- PHPA partially hydrolysed polyacrylamides
- gilsonite partially hydrolysed polyacrylamides
- polyglycerols polyglycerols
- carboxymethylcellulose derivatives such as polyanionic cellulose
- calcium chloride calcium chloride
- sodium silicate sodium silicate
- Potassium chloride combined with PHPA has been widely used, despite the high costs and the difficulty in using the materials.
- Cationic Materials can be higly effective but tend to be incompatible with other additives (mostly anionic) used in water based drilling fluids.
- an additive for a drilling fluid comprising a composition which is at least dispersible in said drilling fluid at ambient temperatures, and has a solubility in said drilling fluid at drilling temperatures which is lower than the solubility at said ambient temperatures, and said exposition, when dispersed in water, has a higher affinity than water for the surface of a rock being drilled.
- composition is substantially insoluble in said drilling fluid at said drilling temperatures; and is soluble at ambient temperatures.
- Ambient temperatures would generally be from 0° to 50°C typically 0o to 30o. The upper end of the range is only likely to be reached in desert areas.
- Drilling temperatures may be anything from ambient up to 200°C or more.
- a typical "bottom hole” temperature in the North Sea would be about 120°C.
- the additive according to the invention will readily mix with the fluid at ambient temperatures, but will come out of solution at drilling temperatures and attach itself to the rock, thereby protecting the rock from hydration by water in the drilling fluid.
- the composition comprises a polymer containing alkylene oxide repeating units.
- the alkylene oxide includes ethylene oxide and/or propylene oxide.
- An ethylene oxide/propylene oxide block copolymer a polyalkylene oxide-modified polymethyl siloxane; a polyalkylene oxide modified polyamine, alcohol or glycerine; and polypropylene glycol.
- the polymer contains 5 to 75 wt% ethylene oxide and 25 to 95 wt% propylene oxide, more preferably 5 to 50 wt% ethylene oxide and 50 to 95 wt% propylene oxide.
- the molecular weight of the polymer is greater than 1000.
- a particularly effective polyalkylene oxide modified diamine is available under the registered trade mark SEPABASE 31. This material is available from BASF.
- a particularly effective polyalkylene oxide modified alcohol is available under the registered trade mark BP 75W 18000. This material is available from BP and is disclosed in a BP publication relating to BREOX polyalkylene glyucol fluids and lubricants.
- additives according to the invention also provide excellent lubricity characteristics, particularly the ethylene oxide/propylene oxide block copolymers.
- the substance may comprise an additive having any combination of the features of the additive described above.
- test was devised to establish a relative measure of shale stabilisation performance for various drilling fluids.
- the test involved static storage of 250 - 1000 micron sieved raw bentonite ore in the fluid under test for 16 hours at 80°C. Afterwards the bentonite was washed with a solution of 10% potassium chloride in tap water, and then resieved. The test was carried out twice for each fluid (test A and test B), and the results are summarised in Table 1.
- test of comparative example 1 was carried cut with a drilling fluid consisting of seawater mixed with 1% by weight of a fluid according to the present invention. The test was carried out twice for each fluid (test C and test D) and the results are summarised in Table 2.
- test E and test F The test of example 1 was repeated using 5% by weight of additive, instead of 1%. The test was carried out twice for each fluid (test E and test F) and the results are summarised in Table 3.
- Comparative example 3 was repeated for three prior art additives, using a different bentonite ore particle size of 1.0 to 2.0 mm.
- Comparative example 2 was repeated, each drilling fluid also being mixed with an additive according to the invention, as well as the prior art additive.
Landscapes
- Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Dispersion Chemistry (AREA)
- Agricultural Chemicals And Associated Chemicals (AREA)
- Compositions Of Macromolecular Compounds (AREA)
- Lubricants (AREA)
Abstract
An additive for a drilling fluid, comprising a composition which is at least dispersible in said drilling fluid at ambient temperatures, and has a solubility in said drilling fluid at drilling temperatures which is lower than the solubility at said ambient temperatures. The composition, when dispersed in water, has a higher affinity than water for the surface of a rock being drilled.
Description
ADDITIVE FOR A DRILLING FLUID
This invention relates to additives for drilling fluids.
Drilling fluids are circulated down the wellbore being drilled during well drilling operations. The fluid is usually pumped down the inside of the drillpipe and then passes through the drill bit into the wellbore. The fluid returns to the surface through the annulus defined between the exterior of the drillpipe and the wellbore. The fluid is then recovered, processed and reused.
Drilling fluids are desirable in order to lubricate the drill bit, to cool the drill bit, and to remove rock cuttings generated.
The physical properties of the drilling fluid (such as viscosity, density, salinity and filtrate loss) can be modified as necessary.
One problem that occurs with water based drilling fluids is hydration of the rock being drilled. This problem is particularly acute when the rock includes clays and shales.
Clays and shales display a great affinity for water. Absorption of water leads to swelling of the clay car shale and the resulting stresses can lead to failure. Thus, when the rock has been hydrated it can be subject to structural failure, and can collapse into the wellbore. This causes wellbore expansion, and can cause the drillpipe to become stuck.
One solution to this problem involves the use of oil based drilling fluids, which are usually formulated with mineral oils. Although these fluids generally contain water, it is tightly emulsified using powerful surfactants. Such fluids are substantially inert to hydratable rocks.
Such oil based drilling fluids are expensive but have been used extensively, particularly in the North Sea area. However, due to environmental problems they are being used less extensively.
Another solution to the problem involves the use of water based drilling fluids which incorporate additives having surface active properties; such additives are sorbed onto the rock, reducing
the access of water, and thereby reducing the rate of hydration. Anionic, cationic and nonionic materials are used, because difference parts of a rock structure shew different affinities to different ionic charges.
Examples of known additives for reducing hydration include: potassium chloride, partially hydrolysed polyacrylamides (PHPA); gilsonite; polyglycerols; carboxymethylcellulose derivatives, such as polyanionic cellulose; calcium chloride; and sodium silicate.
Potassium chloride combined with PHPA has been widely used, despite the high costs and the difficulty in using the materials. Cationic Materials can be higly effective but tend to be incompatible with other additives (mostly anionic) used in water based drilling fluids.
There exists a need for an effective additive for use with water based drilling fluids, which additive is compatible with the other components of drilling fluids.
According to one aspect of the present invention there is provided an additive for a drilling fluid, comprising a composition which is at least dispersible in said drilling fluid at ambient temperatures, and has a solubility in said drilling fluid at drilling temperatures which is lower than the solubility at said ambient temperatures, and said exposition, when dispersed in water, has a higher affinity than water for the surface of a rock being drilled.
Advantageously said composition is substantially insoluble in said drilling fluid at said drilling temperatures; and is soluble at ambient temperatures. Ambient temperatures would generally be from 0° to 50°C typically 0º to 30º. The upper end of the range is only likely to be reached in desert areas.
Drilling temperatures may be anything from ambient up to 200°C or more. A typical "bottom hole" temperature in the North Sea would be about 120°C.
Thus, the additive according to the invention will readily mix with the fluid at ambient temperatures, but will come out of solution at drilling temperatures and attach itself to the rock,
thereby protecting the rock from hydration by water in the drilling fluid.
Preferably the composition comprises a polymer containing alkylene oxide repeating units.
It is particularly preferred that the alkylene oxide includes ethylene oxide and/or propylene oxide.
The polymer may advantageously be selected from the group consisting of:
An ethylene oxide/propylene oxide block copolymer; a polyalkylene oxide-modified polymethyl siloxane; a polyalkylene oxide modified polyamine, alcohol or glycerine; and polypropylene glycol.
It is preferable that the polymer contains 5 to 75 wt% ethylene oxide and 25 to 95 wt% propylene oxide, more preferably 5 to 50 wt% ethylene oxide and 50 to 95 wt% propylene oxide.
Desirably the molecular weight of the polymer is greater than 1000.
A particularly effective polyalkylene oxide modified diamine is available under the registered trade mark SEPABASE 31. This material is available from BASF.
A particularly effective polyalkylene oxide modified alcohol is available under the registered trade mark BP 75W 18000. This material is available from BP and is disclosed in a BP publication relating to BREOX polyalkylene glyucol fluids and lubricants.
Some of the additives according to the invention also provide excellent lubricity characteristics, particularly the ethylene oxide/propylene oxide block copolymers.
According to another aspect of the invention there is provided the use in the wellbore drilling of a stratum, of a saturated or unsaturated aqueous solution of a substance which exhibits a critical solution temperature between ambient temperature and the service temperature at the stratum.
The substance may comprise an additive having any combination of the features of the additive described above.
The invention will now be further described with reference to the following examples.
Comparative Example 1
A test was devised to establish a relative measure of shale stabilisation performance for various drilling fluids. The test involved static storage of 250 - 1000 micron sieved raw bentonite ore in the fluid under test for 16 hours at 80°C. Afterwards the bentonite was washed with a solution of 10% potassium chloride in tap water, and then resieved. The test was carried out twice for each fluid (test A and test B), and the results are summarised in Table 1.
Example 1
The test of comparative example 1 was carried cut with a drilling fluid consisting of seawater mixed with 1% by weight of a fluid according to the present invention. The test was carried out twice for each fluid (test C and test D) and the results are summarised in Table 2.
Example 2
The test of example 1 was repeated using 5% by weight of additive, instead of 1%. The test was carried out twice for each fluid (test E and test F) and the results are summarised in Table 3.
In comparative example l, and examples 1 and 2, swelling leads to particle disintegration and weight loss, although in some cases absorbance can lead to a weight increase. The results from examples 1 and 2 shew that use of 5 wt% of the additive according to the invention, rather than 1 wt%, may lead to a significant improvement in inhibition only with certain additions and that performance may be optimized by suitable material selection.
Comparative Example 2
Comparative example 3 was repeated for three prior art additives, using a different bentonite ore particle size of 1.0 to 2.0 mm.
The tests were repeated twice for each fluid (tests G and H), and the results are summarised in Table 4.
Example 3
Comparative example 2 was repeated, each drilling fluid also being mixed with an additive according to the invention, as well as the prior art additive.
The tests were repeated twice for each fluid (tests I and J), and the results are summarised in Table 5.
A comparison of Table 5 with Table 4 shews that the addition of additives according to the invention to the drilling fluid can cause a significant reduction in weight loss, even when the drilling fluid already contains other additives.
Claims
1. An additive for a drilling fluid, comprising a composition which is at least dispersible in said drilling fluid at ambient temperatures, and has a solubility in said drilling fluid at drilling temperatures which is lower than the solubility at said ambient temperatures, and said composition, when dispersed in water, has a higher affinity than water for the surface of a rock being drilled.
2. An additive according to claim 1, wherein said composition is substantially insoluble in said drilling fluid at said drilling temperatures.
3. An additive according to claim 2, wherein said composition is soluble in said drilling fluid at ambient temperatures.
4. An additive according to claim 1, 2 or 3 wherein said composition comprises a polymer containing alkylene oxide repeating units.
5. An additive according to claim 4, wherein said polymer has a molecular weight of at least 1000.
6. An additive according to claim 4 or 5 wherein said alkyl oxide includes ethylene oxide.
7. An additive according to claim 4, 5 or 6, wherein said alkyl oxide includes propylene oxide.
8. An additive according to claim 3 or 4, wherein said polymer is selected from at least one of the group consisting of: an ethylene oxide/propylene oxide block copolymer; a polyalkylene oxide-modified polymethyl-siloxane; a polyalkylene oxide modified polyamine, alcohol or glycerine; and polypropylene glycoo.
9. An additive according to claim 1, 2, 3 or 4, wherein said polymer contains 5 to 75 wt% ethylene oxide and 25 to 95 wt% propylene oxide.
10. An additive according to claim 1, 2, 3 or 4, wherein said polymer contains 5 to 50 wt% ethylene oxide and 50 to 95 wt% propylene oxide.
11. A drilling fluid comprising a mixture of water and substantially 0.1 to substantially 10 wt% of an additive according to any preceding claim.
12. A drilling fluid according to claim 11, comprising between substantially 0.1% and substantially 5% of said additive
13. A drilling fluid according to claim 11, comprising substantially 1 wt% of said additive.
14. A drilling fluid according to claim 11, 12 or 13, further comprising Bentonite/polyanionic cellulose.
15. A drilling fluid according to claim 11, 12 or 13, further comprising xanthan gum.
16. A drilling fluid according to claim 15, wherein said xanthan gum is saturated with sodium chloride.
17. A drilling fluid according to any of claims 11 to 15, wherein said water is seawater.
18. The use of an additive according to any one of claims 1 to 10 in a drilling fluid.
19. The use in the wellbore drilling of a stratum, of a saturated or unsaturated aqueous solution of a substance which exhibits a critical solution temperature between ambient temperature and the service temperature at the stratum.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| NO931633A NO931633D0 (en) | 1990-11-06 | 1993-05-05 | ADDITIVE TO A DRILL FLUID |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB909024141A GB9024141D0 (en) | 1990-11-06 | 1990-11-06 | Additive for a drilling fluid |
| GB9024141.5 | 1990-11-06 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| WO1992007919A1 true WO1992007919A1 (en) | 1992-05-14 |
Family
ID=10684967
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| PCT/GB1991/001944 WO1992007919A1 (en) | 1990-11-06 | 1991-11-06 | Additive for a drilling fluid |
Country Status (5)
| Country | Link |
|---|---|
| EP (1) | EP0556246A1 (en) |
| AU (1) | AU8859291A (en) |
| CA (1) | CA2095605A1 (en) |
| GB (1) | GB9024141D0 (en) |
| WO (1) | WO1992007919A1 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6242389B1 (en) | 1997-04-14 | 2001-06-05 | Bp Chemicals Limited | Ethers |
| WO2009069057A1 (en) * | 2007-11-26 | 2009-06-04 | Schlumberger Canada Limited | Aqueous two-phase emulsion gel systems for zone isolation |
| WO2017173207A1 (en) * | 2016-04-01 | 2017-10-05 | Saudi Arabian Oil Company | Modification of bentonite properties for drilling fluids |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3018826A (en) * | 1958-06-16 | 1962-01-30 | Union Oil Co | Method for increasing the permeability of subterranean formations |
| US3836465A (en) * | 1972-05-26 | 1974-09-17 | Marathon Oil Co | Composition useful as a fluid loss control agent |
| US3946811A (en) * | 1974-11-25 | 1976-03-30 | Marathon Oil Company | Polyalkene oxide preslug for protecting displacement fluids from polyvalent ions |
| US4005749A (en) * | 1975-11-11 | 1977-02-01 | Mobil Oil Corporation | Oil recovery by surfactant waterflooding |
| US4646834A (en) * | 1980-09-22 | 1987-03-03 | Dowell Schlumberger Incorporated | Aqueous treatment fluid and method of use |
-
1990
- 1990-11-06 GB GB909024141A patent/GB9024141D0/en active Pending
-
1991
- 1991-11-06 EP EP19910919529 patent/EP0556246A1/en not_active Withdrawn
- 1991-11-06 WO PCT/GB1991/001944 patent/WO1992007919A1/en not_active Application Discontinuation
- 1991-11-06 AU AU88592/91A patent/AU8859291A/en not_active Abandoned
- 1991-11-06 CA CA 2095605 patent/CA2095605A1/en not_active Abandoned
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3018826A (en) * | 1958-06-16 | 1962-01-30 | Union Oil Co | Method for increasing the permeability of subterranean formations |
| US3836465A (en) * | 1972-05-26 | 1974-09-17 | Marathon Oil Co | Composition useful as a fluid loss control agent |
| US3946811A (en) * | 1974-11-25 | 1976-03-30 | Marathon Oil Company | Polyalkene oxide preslug for protecting displacement fluids from polyvalent ions |
| US4005749A (en) * | 1975-11-11 | 1977-02-01 | Mobil Oil Corporation | Oil recovery by surfactant waterflooding |
| US4646834A (en) * | 1980-09-22 | 1987-03-03 | Dowell Schlumberger Incorporated | Aqueous treatment fluid and method of use |
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6242389B1 (en) | 1997-04-14 | 2001-06-05 | Bp Chemicals Limited | Ethers |
| WO2009069057A1 (en) * | 2007-11-26 | 2009-06-04 | Schlumberger Canada Limited | Aqueous two-phase emulsion gel systems for zone isolation |
| WO2009070656A2 (en) * | 2007-11-26 | 2009-06-04 | Services Petroliers Schlumberger | Provision of viscous compositions below ground |
| US7703527B2 (en) | 2007-11-26 | 2010-04-27 | Schlumberger Technology Corporation | Aqueous two-phase emulsion gel systems for zone isolation |
| WO2009070656A3 (en) * | 2007-11-26 | 2013-07-25 | Services Petroliers Schlumberger | Provision of viscous compositions below ground |
| US8517102B2 (en) | 2007-11-26 | 2013-08-27 | Schlumberger Technology Corporation | Provision of viscous compositions below ground |
| WO2017173207A1 (en) * | 2016-04-01 | 2017-10-05 | Saudi Arabian Oil Company | Modification of bentonite properties for drilling fluids |
| US10081751B2 (en) | 2016-04-01 | 2018-09-25 | Saudi Arabian Oil Company | Modification of bentonite properties for drilling fluids |
| CN109072057A (en) * | 2016-04-01 | 2018-12-21 | 沙特阿拉伯石油公司 | The improvement of bentonite property for drilling fluid |
| US10793760B2 (en) | 2016-04-01 | 2020-10-06 | Saudi Arabian Oil Company | Modification of bentonite properties for drilling fluids |
Also Published As
| Publication number | Publication date |
|---|---|
| GB9024141D0 (en) | 1990-12-19 |
| EP0556246A1 (en) | 1993-08-25 |
| AU8859291A (en) | 1992-05-26 |
| CA2095605A1 (en) | 1992-05-07 |
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