Evaluation on coalbed methane development potential of gas coal and fat coal reservoirs in China

Tian Zhongbin; Wang Hongdong; Jin Fali; Li Shouping; Wang Haichao; Li Xin

doi:10.13199/j.cnki.cst.2017.02.016

Abstract：In order to evaluate the coalbed methane development potential of the gas coal and fat coal in China,the proximate analysis and macerals data of 81 gas and fat coal samples were collected from the national scope.The tests were conducted on the porosity,mercury injection and other isothermal adsorption.The results showed that the gas coal and fat coal in China mostly were the ultra low ash coal.The crack development of the gas coal and fat coal at each stage would be balance,the micropore of the gas coal and fat coal would be best developed and the large pore and the transition pore would be the second.The total specific pore volume and the porosity would be firstly reduced and then increased with the coal metamorphic degree increased.When 0.65％＜R ＜0.90％,the total specific pore volume and the porosity of the gas coal and fat coal would be decreased with the degree of coalification increased.When R =0.90％,the minimum would be reached.When 0.90％＜R ＜ 1.20％,the total specific pore volume and the porosity would be increased with the degree of coalification increased.The coalbed methane resources of the gas coal and fat coal are rich in China,the ash content of the reservoir would be low,the pore development at each stage would be balanced and the development potential of the coalbed methane would be excellent.