UNDERGROUND GASIFICATION METHOD Russian patent published in 2010 - IPC E21B43/295 

FIELD: mining.

SUBSTANCE: horizontal sections of process wells are located in coal bed. There performed is their breakthrough, ignition, supply of blast air and discharge of production gas. Horizontal sections of process wells in coal bed are of the length which at least twice is more than distance between wells. Wells are located near bed bottom and have enlarged diametre; for that purpose there used are installations of directed drilling. In coal massif above the wells forming a gas generator, within its design outline there made are horizontal sections of decompaction wells. In order to form the latter, there used are installations of directed drilling in drilling mode of pilot wells. For decompaction of coal massif, to decompaction wells there supplied is liquid carbon dioxide, mainly mixed with solid carbon dioxide; after that wells are tightly closed. After decompaction works are completed and aerodynamic connection of decompaction wells and volume of gas generator appears, the latter are used as additional process wells.

EFFECT: stable production of high-caloric gas with high gasification rate of coal bed deposits irrespective of its power and coal strength, and simplifying the method's implementation.

3 cl, 4 dwg