The "Four-in-one" Gas Drainage Technology Based on Horizontal-multilateral Well

For single low permeability thick coal seam, the extraction efficiency of single drilling layout is low, and the integrated stereo drainage can greatly improve the drainage efficiency.This article analyzed the production processes and coal seam geological conditions at N2202 mechanized working face of Yuwu Coal Mine, then proposed "four-in-one"efficient gas drainage technology based on ground horizontal multilateral wells and combined with high-level borehole and plugging pipes on the roof. Through these measures, the gas drainage ratio of N2202 significantly increased to 45% and gas emission in the upper corner was controlled effectively.