淮北煤田煤的介孔孔隙结构及其分形特征分析

Mesopore Structure and Fractal Characteristics of Coals in the Huaibei Coalfield

摘要: 为了定量描述孔隙结构的复杂程度，以淮北煤田的煤为研究对象，分别计算不同煤体结构煤的孔隙分形维数，采用分形模型、对其孔隙结构特征进行了低温N₂吸附性分析。结果表明：煤中组织孔、角砾孔、张裂隙和剪裂隙均有发育。孙疃煤矿样品的平均孔容为0.0025 cm³/100g，平均比表面积为2.021 m²/g。许疃煤矿样品的平均孔容为0.002 cm³/100g，比表面积0.189 m²/g。信湖煤矿样品的平均孔容为0.0083 cm³/100g，比表面积5.89 m²/g。朱仙庄煤矿样品孔容为0.007 cm³/100g，比表面积为0.46 m²/g。煤中介孔以狭窄缝隙形孔、长柱状和平行板状孔为主，同时含有部分两端开口透气孔和少量狭窄墨水瓶形孔。孔隙分形维数D₁介于2.42~2.71，分形维数D₂介于2.43~2.70，表明其具有复杂的孔隙结构。

Abstract: In order to describe the complexity of pore structure, the fractal dimension of coal with different coal structures was calculated, and the adsorption of low temperature N₂ was analyzed by fractal model. This result shows that the tissue pore, gravel pore, tension fractured and shear fractured were developed in coal. The average pore capacity of the sample in Suntuan coal mine is 0.0025 cm³/100g, and the average specific surface area is 2.021 m²/g. The average pore capacity of Xutuan coal mine sample is 0.002 cm³/100g, and the specific surface area is 0.189 m²/g. The average pore capacity of Xinhu coal mine samples is 0.0083 cm³/100g, and the specific surface area is 5.89 m²/g. The pore capacity of the sample in Zhuxianzhuang coal mine is 0.007 cm³/g, and the specific surface area is 0.46 m²/g. The coal intermediary pore is dominated by narrow cracks, long column and parallel plates, with some openness pores at both ends and a small amount of narrow ink bottle pores. The pore fractal dimension D₁ is between 2.42~2.71 and the fractal dimension D₂ from 2.43~2.70, indicating a complex pore structure.