04043393 is referenced by 259 patents and cites 10 patents.

A method of extracting hydrocarbons, energy and other products in situ from an underground coal deposit. A selected part of the coal deposit is heated by electrical induction to temperatures high enough to effect the destructive distillation of coal. The gases and liquids so produced are collected. Next, air or oxygen is injected into the remaining deposit which consists primarily of coke in order to burn it in place. The hot combustion gases thereby yielded are led to the surface of the deposit to generate energy. Lastly, the heat remaining underground after the coke has been burned is extracted by injecting water or steam into the deposit. The resulting steam is conducted to the surface to drive a steam turbine. The electrical induction heating is conveniently effected by passing a selected time varying current through a conductive path encompassing that part of the coal deposit to be heated.

Title
Extraction from underground coal deposits
Application Number
5/709832
Publication Number
4043393
Application Date
July 29, 1976
Publication Date
August 23, 1977
Inventor
Charles B Fisher
2850 Hill Park Road, Montreal, Quebec
CA
Sidney T Fisher
53 Morrison Ave., Montreal, Quebec
CA
Agent
Barrigar & Oyen
IPC
E21B 43/25
E21B 43/24
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