key laboratory of coalbed methane resources and reservoir formation process of the ministry of education;
school of resources and earth science;
china university of mining & technology;
xuzhou 221008;
chi;
huainan mining group;
huainan 232000;
china;
tiefa mining group;
tiefa 112700;
china;
pressure relief coalbed methane; surface wells; well location; Huainan coal mining area;