Evaluation method of coalbed methane surface drainage effect in coal mines——Take a block of Sihe mine as an example

CBM surface exploitation in coal mining area is not only makes use of CBM as a clean energy, but also reduces the risk of coal mine gas accident. Evaluation of CBM surface drainage effect in coal mining area would provides the technical basis for the subsequent CBM development and mining design. Based on the analysis of the surface CBM drainage effect evaluation status, combined with CBM resources development and the coal mine safety, the testing detection and evaluation method of CBM surface drainage effect in coal mining area was proposed, which takes the reduction rate of CBM content and the residual gas content as evaluation indexes, the similar geological conditions of coal reservoir as classification principle of evaluation unit. Under the premise of the classification of the geological conditions of coal reservoir, the classification method of the CBM drainage effect in coal mining area, which is based on the reduction rate of CBM content and residual CBM content, was put forward too. The application of this method in a block of Sihe mine, Jincheng, to a certain extent, proved the rationality and operability of the evaluation method of surface CBM extraction efficiency.