Patent US4688588A successfully refreshed from Google Patents.
US4688588A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Slurry viscosity control
Assignee: WESTERN AUSTALIAN INSTITUTE OF TECHNOLOGY
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Filing: 1985-06-24
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Granted: 1987-08-25
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Expires: 2005-06-24
Abstract
Abstract A method for facilitating the flow of material in fines. The fines are selected from silica based materials and coals; and the level of impurity in the fines and comprising metal oxide, carbonate and sulphides in the case of silica materials, and coal ash in the case of coals, is determined. A thick slurry of the fines in water is prepared, and a quantity of dispersant proportional to the determined level of impurity is added to the slurry to form a pumpable slurry.
Inventors
- 👤 Richard R. Horsley
- 👤 Robert L. Jones
- 👤 Robert J. Snow
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 19:21
CPC Classifications
C; C10; C10L; C10L1/00; C10L1/32; C10L1/326; B; B65; B65G; B65G53/00; B65G53/30; F; F17; F17D; F17D1/00; F17D1/08; F17D1/16; Y; Y10; Y10T; Y10T137/00; Y10T137/0318; Y10T137/0391
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
87 words
A method for facilitating the flow of material in the form of fines, said fines being selected from silica based materials and coals; wherein the level of impurity in the fines and comprising metal oxide, carbonate and sulphides in the case of silica materials, and coal ash in the case of coals, is determined; a thick slurry of said fines in water is prepared; and a quantity of dispersant proportional to the determined level of impurity is added to the slurry to form a pumpalbe said slurry.
Claim 2
Independent Claim
87 words
A method for facilitating the flow of material in the form of fines, said fines being selected from silica based materials and coals; wherein the level of impurity in the fines and comprising metal oxide, carbonate and sulphides in the case of silica materials, and coal ash in the case of coals, is determined; a thick slurry of said fines in water is prepared; and a quantity of dispersant proportional to the determined level of impurity is added to the slurry to form a pumpalbe said slurry.
Claim 3
Dependent Claim
20 words
A method according to claim 1, wherein said dispersant is selected from inorganic sodium phosphates and naphthalene sulphonate aminoplast polymers.
Claim 4
Dependent Claim
27 words
A method according to claim 1 or claim 2, wherein said dispersant is added in an amount of from 0.01 to 0.05% by weight of said fines.
Claim 5
Dependent Claim
40 words
A method according to claim 1 or claim 2, wherein said dispersant is added in an amount of from 0.01 to 0.05% by weight of said fines for an impurity level of up to 10% by weight of said fines.
Claim 6
Dependent Claim
54 words
A method according to claim 1 or claim 2, wherein said fines comprise a silica based material containing water soluble salts of at least one of calcium and magnesium, a precipitant for calcium and magnesium ions being added to said slurry prior to said dispersant to precipitate said ions as a corresponding insoluble compound.
Claim 7
Dependent Claim
12 words
A method according to claim 5, wherein said precipitant is sodium carbonate.
Claim 8
Dependent Claim
40 words
A method according to claim 5, wherein said precipitant is added in excess of requirements to precipitate said ions and the amount of said dispersant is reduced in stoichiometric proportion to said excess by up to about 50% by weight.
Claim 9
Dependent Claim
64 words
A method according to claim 1 or claim 2, wherein said fines comprise a silica based material, sodium carbonate being added to said slurry and the amount of dispersant added to said slurry is reduced by up to about 50% by weight in stoichiometric proportion to any excess of said sodium carbonate above its level necessary to precipitate any ions of calcium and magnesium.
Claim 10
Dependent Claim
23 words
A method according to claim 1 or claim 2, wherein said fines comprise coal fines, said dispersant being a naphthalene sulphonate aminoplast polymer.
Claim 11
Dependent Claim
25 words
A method according to claim 1 or claim 2, wherein said thick slurry is prepared to achieve from 55 to 80% by weight of fines.
Claim 12
Dependent Claim
22 words
A method according to claim 10, wherein said thick slurry is prepared to achieve from 65% to 80% by weight of fines.
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) | 1990-08-24 | 1991-02-23 | 1991-08-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-08-24 | 1995-02-23 | 1995-08-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-08-24 | 1999-02-23 | 1999-08-25 | $7700.00 | Window Closed / Lapsed |