A new thin seam backfill mining technology and its application

Abstract

Backfill mining is an effective way to control ground subsidence and govern gangue. To solve the problem of thin coal seam mining under villages, a new thin seam backfill mining technology was proposed. This paper investigated a reasonable proportion of filling materials by experiments, designed the filling system and introduced key technologies for thin seam working face filling. Finally, an industrial test of thin seam backfill mining technology was carried out in the C1661 working face, Beixu Coal Mine. The results show that the developed filling material meets both the pumping liquidity and strength requirements of the filling body during the early and late stages. The design and equipment selection of the paste filling system were reasonable. By using the key technologies for thin seam working face filling, the time needed for working face filling, the connection and disconnection of the filling pipeline and gob-side entry retaining were all greatly shortened. The labor intensity of the workers was reduced, and the mechanization level of the mine was improved. A fill mining length of 480 m was successfully completed. With effective roof subsidence control, the ground subsidence can be reduced, and good results can be achieved. This study can contribute to the development of backfill mining in thin coal seams.