Experimental study on desorption enhancing of methane in coal mass using a controlled microwave field
HU Guozhong1，2，ZHU Yiran1，2，LI Zhiqiang3
(1. Key Laboratory of Deep Coal Resource Mining，Ministry of Education of China，China University of Mining and Technology，Xuzhou，Jiangsu 221116，China；2. School of Mines，China University of Mining and Technology，Xuzhou，Jiangsu 221116，China；3. Henan provincial Key Lab of Gas Geology and Control-cultivation Base of Provincial and Ministry Joint State Key，Henan Polytecnnic University，Jiaozuo，Henan 454000，China)
Abstract：The controlled microwave field(CMF) is proposed in this paper to address the technical challenge posed by the difficulty in desorption of adsorbed gas during the extraction of coal bed methane. The study on the desorption of methane in coal mass with and without the CMF action was conducted with the gas desorption system with CMF developed in-house. The mechanism of influence of the CMF on the desorption characteristics of methane in coal mass is investigated. It was proved by the experiments that the CMF enhanced the desorption of methane in coal mass and enabled a significant increase in the desorption rate of methane in the coal with the attenuation slowdown. The accumulated amount of methane desorption was increased by 1.65 up to 3.79 times. The shapes of the kinetic curve for the desorption of methane in coal mass remain consistent with or without the CMF action，which may be better depicted by the dynamic diffusion coefficient model. During the same desorbing time，the diffusion coefficient of methane in the coal mass with the CMF action is greater than that of methane without. The CMF may enhance the molecular activity and increase the diffusion coefficient of methane in the coal mass. It alters the differential diffusion resistance of the coal mass during the desorption of methane，thus enables the increase in the desorption and diffusion rate of methane in the coal mass with the decreased diffusion resistance，which promote the desorption of methane in the coal mass.
胡国忠1，2，朱怡然1，2，李志强3. 可控源微波场促进煤体中甲烷解吸的试验研究[J]. 岩石力学与工程学报, 2017, 36(4): 874-880.
HU Guozhong1，2，ZHU Yiran1，2，LI Zhiqiang3. Experimental study on desorption enhancing of methane in coal mass using a controlled microwave field. , 2017, 36(4): 874-880.
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2017, Vol. 36 
