METHOD FOR REMOVING GAS FROM UNFANNED COAL SEAMS Russian patent published in 2012 - IPC E21F7/00 

FIELD: mining.

SUBSTANCE: The method relates to mining and can be used to remove gases from unfanned coal seams. The method includes development of unfanned coal seams, where gas will be removed, by drilling wells. Furthermore, the drilled wells must cross as many macrocracks, microcracks and nanocrack as possible. Water pressure in the wells must not be excessive so that water does not invade into the formation. As coal particles and elements, oxides and substances contained in the said particles change their properties after contact with water, become viscous, form complex molecules, increase their volume and cover almost all cracks in coal, it prevents the passage of methane into drilled wells. In order to achieve this, drill pulp is drifted at the angle of 2-3° through one well and then through another well, beginning from the place of their intersection with coal with subsequent independent drawing, keeping the pulp in the lower part of the well to prevent leakage. The operating well is connected to the vacuum station until methane is completely removed.

EFFECT: increased efficiency of removing gas from unfanned coal seams through drilling well in the said seams, both under the ground and from surface.

3 dwg