Optimization of Longwall Parameters in Underground Mining of Thick Methane-Bearing Coal Seam in the Sokolovo Deposit in Kuzbass

The technical and economic feasibility of increasing the length of longwall 5003 in the the Yalevsky Mine to 400 m and raising output per face to 70 ths t per day in mining thick coal seam is substantiated. It is found that from the condition of the maximum annual profit of the mine, the optimized longwall length is 450 m, and the variants of the longwall lengths of 400 and 512 m are equivalent. The methane release calculations show that at the indicated length and production output of the longwall, it is predicted that methane concentration in return ventilation air is 0.53%, which means null gas criterion constraints.