Patent US3874733A successfully refreshed from Google Patents.
US3874733A
Expired / Lapsed
US
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Hydraulic method of mining and conveying coal in substantially vertical seams
Assignee: C0NSOLIDATION COAL Co
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Filing: 1973-08-29
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Granted: 1975-04-01
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Expires: 1993-08-29
Abstract
Abstract Coal can be mined from a substantially vertical or steeply inclined seam by forming a cavity in the seam and filling the cavity with a magnetite slurry having a specific gravity greater than the coal being mined therefrom. As the coal is dislodged, it will float to the top and be pumped from the cavity by the excess magnetite slurry being supplied to the cavity. A coal-magnetite slurry separator is used to separate the coal from the magnetite slurry, whereupon the magnetite slurry is reinjected into the cavity.
Inventors
- 👤 William N Poundstone
- 👤 William J Miller
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 20:27
CPC Classifications
E; E21; E21B; E21B10/00; E21B10/60; E21B10/26; E21B10/32; E21B43/00; E21B43/29; E21C; E21C41/00; E21C41/16
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
127 words
The method of producing coal from a seam of coal comprising: boring a substantially vertical pilot hole into said seam of coal; inserting a retracted coal dislodging tool into said bored pilot hole; extending said dislodging tool; raise drilling with said extended dislodging tool to form a cylindrical cavity; injecting under pressure into said bored pilot hole and said formed cavity, material having a specific gravity greater than said coal; removing said dislodged coal and said material through said pilot hole; separating accumulated amounts of said dislodged coal and material being removed from said bored pilot hole; re-injecting said separated material into said bored pilot hole; and continuing to raise drill until said dislodging tool is in close proximity to the surface of said seam of coal.
Claim 2
Independent Claim
127 words
The method of producing coal from a seam of coal comprising: boring a substantially vertical pilot hole into said seam of coal; inserting a retracted coal dislodging tool into said bored pilot hole; extending said dislodging tool; raise drilling with said extended dislodging tool to form a cylindrical cavity; injecting under pressure into said bored pilot hole and said formed cavity, material having a specific gravity greater than said coal; removing said dislodged coal and said material through said pilot hole; separating accumulated amounts of said dislodged coal and material being removed from said bored pilot hole; re-injecting said separated material into said bored pilot hole; and continuing to raise drill until said dislodging tool is in close proximity to the surface of said seam of coal.
Claim 3
Dependent Claim
88 words
A method as described in claim 1 wherein said method includes: boring another substantially vertical pilot hole in said seam of coal in the proximity of said first-mentioned formed cavity; inserting said retracted coal dislodging tool into said another bored pilot hole; extending said retracted coal dislodging tool and raise drilling to form a cavity; injecting water through said first-mentioned bore hole and into said cavity to remove said material therefrom; separating said material from said injected water; and inserting said separated material into said another bore hole.
Claim 4
Dependent Claim
18 words
A method as defined in claim 2 wherein said material comprises a slurry formed from magnetite and water.
Claim 5
Dependent Claim
63 words
A method as defined in claim 3 wherein said magnetite slurry and water removed from the bottom of said bore hole is further processed by: separating said magnetite from said water; mixing said separated magnetite with water to form a slurry having a predetermined specific gravity; adding said slurry to said another bore hole; and returning said separated water to said bore hole.
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) | 1978-03-31 | 1978-09-30 | 1979-04-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-31 | 1982-09-30 | 1983-04-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-31 | 1986-09-30 | 1987-04-01 | $7700.00 | Window Closed / Lapsed |