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US3696923A Expired / Lapsed US ⏱️ 0.0 years remaining

Method for recovering fine coal and coal-containing particles in a coal recovery circuit

Assignee: Bethlehem Steel Corp
•
Filing: 1970-07-28
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Granted: 1972-10-10
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Expires: 1990-07-28
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Abstract

Abstract Improved method of treating a fine coal slurry from a coarse coal washing circuit and/or a slurry from a fine coal recovery circuit wherein the slurries are passed to a first frothflotation step to recover a substantial portion of the fine particles of coal therein as a froth product, dewatering the froth product to obtain a cake product containing usable coal and an effluent containing substantially all finely divided coal particles. The effluent is passed to a second series of frothflotation cells wherein the fine particles of coal are removed as a second froth product and substantially clean water is recovered as the tailings product. The second froth product is returned to the recovery circuit wherein the fine particles of coal are recovered. The tailings product may be recycled if desired.

Inventors

  • 👤 Francis G Miller

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-02 06:04
CPC Classifications
B; B03; B03B; B03B7/00; B03B9/00; B03B9/005

Claims Analysis

Total Claims: 0
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References Cited (Backward Citations)

US2970689A Cited
US3043426A Cited
US3200068A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1975-10-10 1976-04-10 1976-10-10 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1979-10-10 1980-04-10 1980-10-10 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1983-10-10 1984-04-10 1984-10-10 $7700.00 Window Closed / Lapsed

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