酸化作用前后煤样吸附甲烷特性研究

Study on methane adsorption characteristics of coal samples before and after acidification

为了研究酸化前后煤样的吸附特性,以宜宾白胶煤矿煤为研究对象,通过研磨筛选部分煤粒进行酸化脱灰处理,对煤孔隙进行了表征,并进行了等温吸附试验,探究储层温度下甲烷吸附特性。试验结果表明:酸化脱灰后,煤样比表面积、孔体积增加;由于酸化处理,使得煤样内部的矿物或杂质被移除,孔径增大,孔的面积以及孔的数量增多,等温吸附试验中,酸化处理煤样YB2的平衡时吸附量明显大于没有经过处理的YB1煤样;运用吸附势理论探究得到在一定的储层温度下孔隙结构的改变对煤吸附瓦斯有较大的影响。

In order to study the adsorption features of the coal sample before and after the acidation,the coal of Yibin Baijiao Mine was taken as the main study object,an acidation and deashing treatment were conducted on the partial coal particles from the grinding and screening and the coal pores was characterizationed.The methane adsorption features under the reservoir temperature was explored by isotherm adsorption test.The test results showed that after the acidation and deashing conducted,the specific surface area and the pore volume of the sample were increased. Due to the acidation treatment,the minerals or impurities within the coal samples would be removed,the pore diameter could be increased and the pore area and pore number could be increased. In the isotherm adsorption test,the balance adsorption volume of the coal sample YB2 with the acidation treatment would be obviously higher than the coal sample YB1 with no acidation treatment. The adsorption potential theory was applied to explore the pore structure variation under a certain reservoir temperature highly affected to the coal adsorption gas.