西山煤田焦煤孔隙结构对瓦斯解吸的影响研究  

Study on the influence of coking coal pore structure on methane desorption in Xishan Coalfield

作　　者：徐慧刚 秦兴林 XU Huigang;QIN Xinglin(Shanxi Xinyuan Coal Co.,Ltd.,Jinzhong 045411,China;China Coal Technology and Engineering Group Shenyang Research Institute,Fushun 113122,China;State Key Lab of Coal Mine Safety Technology,Fushun 113122,China)

机构地区：[1]山西新元煤炭有限责任公司,山西晋中045411 [2]中煤科工集团沈阳研究院有限公司,辽宁抚顺113122 [3]煤矿安全技术国家重点实验室,辽宁抚顺113122

出　　处：《煤矿安全》2022年第5期7-12,共6页Safety in Coal Mines

基　　金：国家自然科学基金面上资助项目(51374216)。

摘　　要：为了研究西山煤田焦煤的微观孔隙特征及其对瓦斯解吸的影响规律,采用低温液氮吸附法,针对6个典型焦煤煤样的孔隙结构进行测试,将实验结果与焦煤瓦斯解吸特性相结合,从微观角度分析了孔隙结构对焦煤瓦斯解吸的影响。研究结果表明:焦煤孔隙体积、孔比表面积变化较大,分别在0.017 4~0.081 3 cm^(3)/g、0.84~2.59 m^(2)/g范围内变动;在焦煤的各类孔隙中,微孔最为发育,主要占据了孔隙表面积,而微孔体积很小,孔隙体积主要由大孔和中孔贡献;孔隙体积是影响焦煤瓦斯解吸的主要因素,但同时孔表面积的增加对解吸量也有积极贡献;焦煤水分含量对瓦斯解吸有重要影响,水分易堵塞煤体孔裂隙通道,抑制焦煤瓦斯解吸,进而降低总解吸量。In order to investigate the pore characteristic of coking coal in Xishan Coalfield and its influence on methane desorption, cryogenic liquid nitrogen adsorption method was used to analyze the pore structures of six typical coking coal samples.Combining the experimental results with methane desorption, the effect of pore structures on methane desorption characteristics of coking coal was analyzed from the micro level. The results show that both pore volume and pore specific surface area of coking coals are changed in the wide range of 0.017 4-0.081 3 cm^(3)/g and 0.84-2.59 m^(2)/g, respectively. Micropores are most developed among all the pore types in coking coal, and they mainly occupy the pore surface area. However, micropore volume is small, and pore volume is mainly contributed by macropores and mesopores. Pore volume is the main influencing factor of coking coal desorption, simultaneously the increase of pore surface area also contributes to gas desorption. Moisture content in coking coal has great impact on gas desorption. It is easy for water molecules to block the pore-fracture channels, further to inhibit gas desorption,leading to the reduction of total desorption volume.

关 键 词：焦煤 孔隙结构 瓦斯解吸 西山煤田 影响机理 

分 类 号：TD712[矿业工程—矿井通风与安全]