US3633689A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for drilling wells
Assignee: ExxonMobil Upstream Research Co
•
Filing: 1970-05-27
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Granted: 1972-01-11
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Expires: 1990-05-27
Abstract
Abstract Drilling of wells in subfreezing environments is conducted by using a fluid which contains a major amount of an aqueous medium such as sea water or fresh water, a heteropolysaccharide produced by the action of bacteria of the genus Xanthomonas, an oxygenated hydrocarbon dispersant which may be a polyhydric alcohol such as ethylene glycol and, optionally, an alkaline medium to provide a desired pH, the polyhydric alcohol aiding in the dispersion of the heteropolysaccharide in the aqueous medium and acting as a freezing point depressant of the drilling fluid.
Inventors
- 👤 Stanley A Christman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 16:02
CPC Classifications
C; C09; C09K; C09K8/00; C09K8/02; C09K8/04; C09K8/06; C09K8/08; C08; C08K; C08K7/00; C08K7/02; Y; Y10; Y10S; Y10S166/00; Y10S166/901; Y10S507/00; Y10S507/903
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
17 words
A method in accordance with claim 1 in which the heteropolysaccharide is heteropolysaccharide produced by Xanthomonas campestris.
Claim 2
Dependent Claim
33 words
an amount of a heteropolysaccharide produced by the action of the genus Xanthomonas on a carbohydrate within the range from about 0.05 to about 5.0 percent by wt. of the aqueous medium; and
Claim 3
Dependent Claim
30 words
an amount of an oxygenated dispersant within the range of about 2.0 to about 30 percent by wt. of the aqueous medium; and c. recovering cuttings from said well bore.
Claim 4
Dependent Claim
17 words
A method in accordance with claim 1 in which the well is drilled in a subfreezing environment.
Claim 5
Dependent Claim
14 words
A method in accordance with claim 3 in which the subfreezing environment includes permafrost.
Claim 6
Dependent Claim
16 words
A method in accordance with claim 3 in which the subfreezing environment is in the Arctic.
Claim 7
Dependent Claim
15 words
A method in accordance with claim 1 in which the aqueous medium is sea water.
Claim 8
Dependent Claim
14 words
A method in accordance with claim 1 in which the aqueous medium is brine.
Claim 9
Dependent Claim
15 words
A method in accordance with claim 1 in which the aqueous medium is fresh water.
Claim 10
Dependent Claim
16 words
A method in accordance with claim 1 in which the aqueous medium comprises a drilling mud.
Claim 11
Dependent Claim
16 words
A method in accordance with claim 1 in which the oxygenated dispersant is a polyhydric alcohol.
Claim 12
Dependent Claim
15 words
A method in accordance with claim 1 in which the oxygenated dispersant is ethylene glycol.
Claim 13
Dependent Claim
41 words
A method in accordance with claim 1 in which the heteropolysaccharide is further dispersed by the addition of an amount of an alkaline medium sufficient to provide a pH in said fluid within the range of about 8 to about 10.
Claim 14
Dependent Claim
17 words
A method in accordance with claim 12 in which the heteropolysaccharide is heteropolysaccharide produced by Xanthomonas campestris.
Claim 15
Dependent Claim
20 words
A method in accordance with claim 12 in which the alkaline medium is a solution of an alkali metal hydroxide.
Claim 16
Dependent Claim
28 words
A method in accordance with claim 1 in which the heteropolysaccharide is cross-linked with a polyvalent metal cation selected from Groups III through VIII of the Periodic Table.
Claim 17
Dependent Claim
13 words
A method in accordance with claim 1 in which the heteropolysaccharide is cross-linked.
Claim 18
Dependent Claim
18 words
A method in accordance with claim 1 in which the heteropolysaccharide is cross-linked with a trivalent chromium compound.
Claim 19
Dependent Claim
15 words
A method in accordance with claim 1 in which the heteropolysaccharide is cross-linked with chrome-alum.
Claim 20
Dependent Claim
30 words
A method in accordance with claim 1 in which: a. the oxygenated dispersant is ethylene glycol; b. the heteropolysaccharide is Xanthomonas campestris; and c. the aqueous medium comprises sea water.
Claim 21
Dependent Claim
41 words
A method in accordance with claim 19 in which the heteropolysaccharide is further dispersed by the addition of an amount of an alkaline medium sufficient to provide a pH in said fluid within the range of about 8 to about 10.
Claim 22
Dependent Claim
18 words
A method in accordance with claim 19 in which the fluid is maintained at temperatures below 32* F.
Claim 23
Dependent Claim
13 words
A method in accordance with claim 1 in which the heteropolysaccharide is cross-linked.
References Cited (Backward Citations)
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US3251768A
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US3179528A
Cited
US3198268A
Cited
US3319715A
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US3243000A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-01-10 | 1975-07-12 | 1976-01-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-01-10 | 1979-07-12 | 1980-01-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-01-10 | 1983-07-12 | 1984-01-11 | $7700.00 | Window Closed / Lapsed |