Study on process and model of CBM dissipating  

作　　者：Feng Hong Yan Song Zhenhong Chen Mengjun Zhao Shaobo Liu Shengfei Qin Guoyou Fu 

机构地区：[1]Petro China, Res Inst Petr Explorat & Dev, Beijing 100083, Peoples R China

出　　处：《Chinese Science Bulletin》2005年第S1期134-139,共6页

摘　　要：Coal Bed Methane(CBM) occurs in coal seams in the states of adsorption gas, free gas and water-dissolved gas. Its dissipating starts with desorption, and then it dissipates outwards in the states of free gas and water-dissolved gas. The dissipating approach is classified to three patterns: Free gas in pores dissipates through the cover rocks; hydrocarbon molecules in the cap-rocks and reservoir diffuse because of concentration gradient; gas dissolving in water is directly taken away by water. According to the controlling factors of CBM conservation and considering the cover rocks, soleplate, hydrological region identification and dissipating theory, three geological models of CBM dissipating are built: closed system model, lateral hydrological closed model and open system model.Coal Bed Methane(CBM) occurs in coal seams in the states of adsorption gas, free gas and water-dissolved gas. Its dissipating starts with desorption, and then it dissipates outwards in the states of free gas and water-dissolved gas. The dissipating approach is classified to three patterns: Free gas in pores dissipates through the cover rocks; hydrocarbon molecules in the cap-rocks and reservoir diffuse because of concentration gradient; gas dissolving in water is directly taken away by water. According to the controlling factors of CBM conservation and considering the cover rocks, soleplate, hydrological region identification and dissipating theory, three geological models of CBM dissipating are built: closed system model, lateral hydrological closed model and open system model.

关 键 词：CBM dissipate cap-rocks HYDROGEOLOGY CONSERVATION model. 

分 类 号：P618.13[天文地球—矿床学]