Patent US3737037A successfully refreshed from Google Patents.
US3737037A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Drilling fluid treatment
Assignee: Atlantic Richfield Co
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Filing: 1971-05-03
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Granted: 1973-06-05
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Expires: 1991-05-03
Abstract
Abstract A method for treating well drilling fluid to remove substantially all suspended solid particles wherein the drilling fluid is centrifuged to remove particles of sizes down to about 20 microns in diameter followed by adding a flocculating agent to form flocs of particles from about 20 microns to less than 2 microns in diameter, and filtering the flocs from the drilling fluid to provide a liquid substantially free of suspended solid particles for reuse as a drilling fluid.
Inventors
- 👤 L Bone
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 22:48
CPC Classifications
B; B03; B03B; B03B7/00; E; E21; E21B; E21B21/00; E21B21/06; E21B21/063; E21B21/065
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
35 words
A method according to claim 1 wherein said centrifuging to remove weighting material is accomplished with a mechanical decanting centrifuge, and said centrifuging to remove less dense particles is accomplished with a nonmechanical cyclone centrifuge.
Claim 2
Dependent Claim
50 words
A method according to claim 1 wherein said at least one flocculating agent is selected from the group polyacrylates; polyacrylamides; polyamines; polyamides; partially hydrolyzed polyacrylamides; methylcellulose; carboxymethylcellulose; alkali metal carboxymethylcellulose; halides of aluminum, iron, nickel, and cobalt; aluminum sulfate; alkali metal aluminate; alum; bentonite; attapulgite; sepiolite; hydrous mica; and kaolin.
Claim 3
Dependent Claim
35 words
A method according to claim 1 wherein said at least one flocculating agent is added to said drilling fluid in an amount sufficient to form flocs that will be retained on a 200 mesh sieve.
Claim 4
Dependent Claim
41 words
A method according to claim 1 wherein said at least one flocculating agent is added to said drilling fluid in an amount of from about 0.01 ppm to about 5 weight percent based on the total weight of the drilling fluid.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-06-04 | 1976-12-04 | 1977-06-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-06-04 | 1980-12-04 | 1981-06-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-06-04 | 1984-12-04 | 1985-06-05 | $7700.00 | Window Closed / Lapsed |