Analysis on effect of gas production and influence factors of CBM separate layer pressure control and multi-layer drainage in tectonic coal mining area

According to the status of structural coal development and serious gas hazard in Pingdingshan Mining Area, in order to study the applicability of separate-layer pressure control and multi-layer drainage technology in the Shoushan No.1 Coal Mine of Pingdingshan Mining Area, the effect of gas production and influence factors of separate-layer pressure control and multi-layer drainage for No.4-2 and No.2-1 coal seam have been analyzed, and the reason of poor gas production of separate-layer pressure control and multi-layer drainage for No.4-2 and No.2-1 coal seams is discussed. The result indicates that the pressure,pressure gradient,permeability,properties of the roof with backplane and hydrogeological conditions are similar, and this has not influenced the multi-layer draining effect; the larger coal seam spacing, the smaller critical desorption pressure of No.2-1 coal seams and the soft structure of No.4-2 coal seams have seriously influenced on the multi-layer draining effect and cause poor gas production. So the technology of separate-layer pressure control and multi-layer drainage is not suitable for No.4-2 and No.2-1 coal seams of Shoushan No.1 Coal Mine.