METHOD OF PURIFICATION OF UNDERGROUND WATER IN WORKED-OUT SPACE OF UNDERGROUND GAS-GENERATOR Russian patent published in 2009 - IPC C02F3/34 E21B43/295 

FIELD: mining.

SUBSTANCE: according to invention there is used biological method of decomposition and neutralisation of chemical impurities generated in process of coal gasification in total underground gas generator equipped with primary reaction channel of gasification and with series of boreholes. Upon completion of coal gasification and filling worked out space of the underground gas generator with underground water, bacterial medium is periodically introduced via boreholes into underground water of worked out space of the gas-generator; also alkaline medium of underground water with pH=7.5÷9 is maintained by means of supplying solution of Na₂CO₃ into underground water of worked out space of the gas-generator via boreholes. Types of bacteria of bacterial medium are chosen with consideration of composition and concentration of chemical impurities in underground water, for the purpose of which their samples are periodically taken and subjected to chemical analysis. Also firing borehole of the primary reaction channel of gasification and/or at least one vertical borehole are used as boreholes for air pumping, while blowing and/or gas withdrawing boreholes are used as air withdrawing boreholes.

EFFECT: preventing pollution of environment due to increased efficiency of purifying underground water from chemical impurities created at underground gasification of coal.

5 cl, 3 dwg