Coalbed would be damaged by fracturing fluid, which affects coalbed methane production. Clean fracturing fluid is studied through experiments on the diffusion of coalbed methane desorption and seepage damage mechanism to provide a theoretical basis for the selection of coalbed methane well fracturing fluid. Coal 3 from Qinshui basin is selected as test samples to conduct the desorption test after injecting fracturing liquids into the samples by using independently developed CBM desorption experimental apparatus and permeability test by microscopic distribution of fluid simulation experiment system. Research shows that permeability of coal is damaged by 30% and the desorption amount of damage rate is 24%. Clean fracturing fluid may postpone the coalbed methane desorption time and reduce the absorption rate. And then through the electron microscope scanning and wettability analysis, the damage mechanism of coal by clean fracturing fluid is found out.

coalbed methane  /  clean fracturing fluid  /  permeability  /  desorption  /  wettablilty