PROCESS OF OUTGASSING OF COAL FORMATION Russian patent published in 2003 - IPC

FIELD: mining industry. SUBSTANCE: process can be utilized for intensification of outgassing. Technical result of invention lies in increased safety of mining operations thanks to more complete outgassing of coal formation through holes by rise of pressure, temperature and range of action of cracks and pores in formation. With this in mind holes are drilled, cased and their mouths are sealed. Liquid is pumped through hole into coal formation in turn under static and pulse modes. At same time cumulative and thermal stimulation is carried out. Then holes are linked to outgassing pipe-line and gas is recovered. Cumulative and thermal stimulation is carried out in stages: first at temperature 80-290 C and pressure 8.0-15.0 MPa, then at temperature 290-360 C and pressure 15.0-22.0 MPa and finally at temperature above 375 C and pressure over 22.0 MPa. Cumulative and thermal stimulation in formations displaying low gas permeability is executed at temperature over 375 C and pressure exceeding 22.0 MPa. EFFECT: increased safety of mining operations. 3 dwg, 1 tbl