DEVELOPMENT METHOD FOR THICK STEEP COAL BED LIABLE TO SPONTANEOUS IGNITION Russian patent published in 2006 - IPC E21C41/18 

FIELD: mining industry, particularly methods of underground mining.

SUBSTANCE: method involves dividing coal bed into levels by drilling ventilation drifts and entries on upper and lower level boundaries correspondingly; forming sublevel crosscuts and sublevel drifts, which divide levels into sublevels; top-down cutting mineral bed; bypassing caving rock of damaged roof in excavated cavity of sublevels to be treated. The bed is cut without coal pillar establishment between neighboring cavities of adjacent levels. The first to be developed is lower sublevel, which is prepared to development by boring stowing drifts along upper border of above sublevel at bed roof and by boring sublevel drift along lower border thereof at ledge wall of the bed. Lower sublevel is developed in several slices, wherein coal in each slice of sublevel to be stowed is cut by hydraulic monitor to stowing drift to form slide ground surface extending at angle α=45° to rock stratifying plane. Then full filling of excavated cavity is performed within the limits of slices. The excavated cavities are filled with hardening material and the stowing massif is formed as rectangular prism with triangle lying at base thereof. After that level is cut in top-down order beginning from upper sublevel.

EFFECT: reduced coal losses and decreased fire hazard.

1 dwg