Influence mechanism of alkaline solution on methane adsorption of coal

doi:10.16265/j.cnki.issn1003-3033.2020.04.005

Abstract

Abstract: In order to explore alkaline solution's enhancement on coal's chemical permeability, pore test and adsorption test were carried out to analyze influence of alkaline solution on chemical erosion effect of coal and its adsorption capacity of methane. With Qingdong coal mine from Anhui Province as research object, samples' pore and methane capacity characteristics before and after alkaline solution treatment were tested with low temperature liquid nitrogen adsorption method and isothermal adsorption method. Then, experiment results were quantitatively discussed using fractal theory and adsorption theory. The results show that alkaline solution can effectively change pore structure of coal and increase content of micropores at pore size less than 5 nm. Coal samples' adsorption capacity greatly improves with its maximum value increasing from 17.83 mL/g to 21.97 mL/g after alkali treatment.

Key words: alkaline solution, coal, methane adsorption, clay minerals, pore structure

CLC Number:

X936

ZHOU Yinbo, WANG Siqi, ZHAO Zhou, GUAN Pinpin, XU Jingxin, WU Jin'gang. Influence mechanism of alkaline solution on methane adsorption of coal[J]. China Safety Science Journal, 2020, 30(4): 28-32.

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