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US3579442A Expired / Lapsed US ⏱️ 0.0 years remaining

Coal converting process

Assignee: Bird Machine Co Inc
•
Filing: 1970-07-09
•
Granted: 1971-05-18
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Expires: 1990-07-09
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Abstract

Abstract A PROCESS FOR CONVERTING COAL CONTAINING REFUSE TO A USEABLE COAL PRODUCT OF A PREDETERMINED MAXIMUM MOISTURE CONTENT, COMPRSING THE STEPS OF SEPARATING WET, REFUSE-CONTAINING COAL INTO FRACTIONS ACCORDING TO PARTICLE SIZE, INCLUDING A FINEST FRACTION AND ONE OR MORE LARGER FRACTIONS, REMOVING REFUSE AT LEAST FROM THE LARGER FRACTIONS, DEWATERING THE LARGER FRACTION TO A MOISTURE CONTENT BELOW HE PREDETERMINED MAXIMUM, AND MECHANICALLY DEWATERING THE FINEST FRACTION IN A CONTINUOUS CENTRIFUGE CONSTRUCTED TO PROVIDE A FINEST COAT OUTPUT HAVING A MOISTURE CONTENT ABOVE THE PREDETERMINED MAXIMUM WHICH, WHEN THE FRACTIONS ARE ALL RECOMBINED, WILL PROVIDE A COMBINED OISTURE CONTENT WITHIN THE PREDETERMINED MAXIMUM TO FORM SAID PRODUCT.

Inventors

  • 👤 Jack N Gerwig

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-26 08:38
CPC Classifications
B; B03; B03B; B03B9/00; B03B9/005; C; C10; C10L; C10L9/00

Claims Analysis

Total Claims: 0
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References Cited (Backward Citations)

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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1974-05-17 1974-11-16 1975-05-18 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1978-05-17 1978-11-16 1979-05-18 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1982-05-17 1982-11-16 1983-05-18 $7700.00 Window Closed / Lapsed

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