04099567 is referenced by 231 patents and cites 12 patents.

Medium BTU gas is generated from coal in situ by establishing communication channels through the coal in part by projectiles and in part by burning. Oxygen is employed for reaction with the coal and reaction temperatures are controlled by injection of steam.

Title
Generating medium BTU gas from coal in situ
Application Number
5/801223
Publication Number
4099567
Application Date
May 27, 1977
Publication Date
July 11, 1978
Inventor
Ruel Carlton Terry
Denver
CO, US
Assignee
In Situ Technology
CO, US
IPC
E21C 43/00
E21B 43/26
E21B 43/24
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