METHOD OF MINING THICK GASSY FLAT SEAMS (VERSIONS) Russian patent published in 2000 - IPC

FIELD: mining; particularly, methods of control of gas-dynamic phenomena and safe mining operations. SUBSTANCE: method may be realized in two versions: (1) drilling of blast holes in floor of central development working of longwall upper layer, with blast hole length of not less than total thickness of interlayer band, lower layer and uniform layer of underlying rock with interval not in excess of half of caving step of main roof caving in worked-out space of lower layer longwall with their subsequent final drilling and blasting in mining of lower layer longwall; with blasting effected after advance of support in worked-out space of lower longwall; (2) drilling of blast holes directly from face space of lower layer longwall with the same half step but with depth not less than thickness of only uniform layer of underlying rocks with their subsequent blasting in worked-out space directly behind guarding shields of support unit after its advance. EFFECT: higher safety of mining operations, excluded instantaneous outbursts of salt and gas from floor of layer workings. 2 cl, 2 dwg