不同破坏程度煤的孔隙特征差异对比研究

A comparative study on difference of pore characteristics of coal with different deformation degrees

为了查明中煤阶不同破坏程度煤的孔隙特征差异,运用低温液氮法对平顶山四矿不同破坏程度的煤样进行测试,对比分析得出了其孔隙结构及分布、分形特征和吸附性能的差异。结果表明:碎裂煤和碎粒煤的吸附平衡等温线为III型,内部大孔发育;糜棱煤为IV型,介孔含量较多;煤的破坏程度越强,总孔体积和比表面积越大,煤内部孔隙结构越复杂,氮气吸附量越大;2~4 nm孔隙的氮气吸附量主要受控于该尺度孔隙的比表面积;孔径>4 nm的则主要受控于该尺度孔隙的孔体积。

In order to find out the difference of pore characteristics of medium rank coal with different degrees of destruction, the low temperature liquid nitrogen method was used to test coal samples with different degrees of destruction in Pingdingshan No.4 mine, and the difference of pore structure, distribution, fractal characteristics and adsorption performance were obtained by comparative analysis. The results showed that the adsorption equilibrium isotherm of cataclastic coal and fragmented coal were type Ⅲ, and the macropores were developed. Mylonite coal was type Ⅳ with high mesoporous content. The greater the degree of coal destruction is, the greater the total pore volume and specific surface area is, the more complex the internal pore structure is, and the greater the nitrogen adsorption capacity is. The nitrogen adsorption capacity of 2-4 nm pores was mainly controlled by the specific surface area, while the pore diameter of more than 4 nm was mainly controlled by the pore volume.