基于煤的微观结构特征的实验方法对比分析

Comparative Analysis of Experimental Methods Based on Microstructure Characteristics of Coal

“十四五”期间“天蓝地绿水清”的生态环保要求准确测算不同煤阶煤的煤层气含量。煤的表面微观结构对煤层气吸附有决定作用。文章通过对比煤的微观孔隙实验方法,发现不同实验方法对孔隙分布的测算结果不同。压汞实验适用测算孔径范围为0.003~400μm的孔及裂隙,液氮实验适用测算孔径范围为0.4~500 nm的微小孔和中孔,更小孔径的结构测算应用小角X射线散射光电实验更为合宜。3种实验方法对各个数学模型构建、实验条件设置和实验样品处理有不同要求。通过系统分析实验原理和测算方法并给出应用建议,对准确测试煤的微观结构有重要作用。

During the 14th Five-Year Plan period,"blue sky,green land,clear water"ecological and environmental protection requirements have led to accurate estimation of coalbed methane content in different coalmines.Through the study of coal pore,it was found that the measurement results were different by different experimental methods.Through the comparison of three kinds of experimental methods,it was found that the mercury injection experiment is suitable for the measurement of large pores with an aperture range of 3 nm to 400μm,and the liquid nitrogen experiment is suitable for the medium pores with the aperture range of 0.4 nm to 500 nm.The small angle X-ray scattering photoelectric experiment is more suitable for the measurement of small holes and micro holes.In addition,the three methods have different requirements for mathematical model construction,experimental conditions setting and experimental sample processing.Through systematic analysis of experimental principle and calculation method,the application suggestions are given,which plays an important role in accurately testing the microstructure of coal.