Experimental Study on Water Infusion in Less Pore and Hard Coal Seam

Through the analysis of the plastic deformation of coal seam caused by the support pressure, we thought that it formed hole (crack) gap regeneration area, hole (crack) gap close area and the original hole (crack) gap area ahead of the coal wall. According to plastic range data of theoretical calculation in 2-508 face of Sanjiaohe Coal Mine, we determined three areas. By reasonable choice of infusion parameter in three areas, the final moisture of coal is increased from 1.07% to 2.51%. The removal efficiency of total dust in coal face increased to 74%, and the removal efficiency of respirable dust is increased to 56%. Using different pore fracture characteristics of face, adopting the corresponding coal seam water injection parameters can effectively improve the effect of coal seam water injection.