METHOD OF INCREASING WATER AND GAS FLOW RATE OF HORIZONTAL COAL-METHANE WELLS Russian patent published in 2025 - IPC E21B43/16 

FIELD: mining.

SUBSTANCE: invention relates to production of methane from coal beds and can be used in cleaning horizontal shafts of coal-methane wells in a system with vertical wells and increasing gas recovery of exposed coal beds. Method involves continuous monitoring of readings of a bottomhole pressure sensor installed in a vertical coal-methane well, drying the shaft of a horizontal coal-methane well by pumping nitrogen until the moment of termination of fluid output from the well through the flow line. Nitrogen injection is continued until the pressure in the well is reached, which corresponds to the maximum geostatic pressure, then pressure in the injection line is created not less than the pressure in the horizontal coal-methane well. Pumping of aerated solution is started in horizontal methane-coal well in volume equal to volume of well system, after which nitrogen pumping is continued till pressure value in well reaches about 80% of formation hydraulic fracturing pressure. Nitrogen injection is stopped, the injection line is shut off and pressure relief is started in the horizontal coal-methane well through the flow line at a rate of not more than 10 atm/min, after pressure relief in horizontal methane-coal well to atmospheric pressure, well is closed and fluid level is maintained below productive formation.

EFFECT: increased flow rate of water and gas due to cleaning of shafts of horizontal coal-methane wells from coal fines and other colmatants.

1 cl, 1 dwg