Experimental Study on COALBED Methane Desorption During High-Pressure Water Injection
In order to study influences of high-pressure water injection on coalbed methane desorption, coalbed methane desorption experiment, permeability testing and observing microcracks under microscope were used to test and analyze the coalbed methane desorption regulation of anhydrous invasion and high-pressure water injection in the Qinshui Basin. There were three kinds of influences on coal structures from high-pressure water, connecting cracks, generalizing new fractures and broadening them. After high-pressure water injecting into coal, permeability reduced resulting from the moisture in it at the early stage of desorption, which restrained coalbed methane desorption. In the late stage of desorption permeability raised because pore water was pumped out of coal, which improved the coalbed methane desorption.
Keywords: High-Pressure Water Injection; Desorption; Cola; Moisture; Permeability; Strain