微生物作用下煤体微观结构演化特征研究

Study on the Evolution Characteristics of Coal Microstructure Under the Action of Microorganisms

为研究功能微生物作用下煤体微观结构演化特征,选用山西寺河矿无烟煤作为底物,添加功能菌剂进行微生物厌氧降解煤驱动瓦斯解吸实验。通过压汞实验、低温N_2吸附实验和X射线衍射仪测试分别对微生物降解前后煤孔隙结构发育及晶体结构演化特征进行表征。研究发现:微生物降解后,一方面煤体微孔、过渡孔、中孔孔容及比表面积下降,大孔孔容及平均孔径得到显著提升,煤体孔隙结构发育明显;另一方面,煤体结晶度降低,内部晶体结构变疏松,大分子间排列更加无序。煤在功能微生物降解后实现增透效果,吸附能力降低,从而促使煤体内瓦斯快速解吸。

In order to study the evolution characteristics of coal microstructure under the action of functional microorganisms,Anthracite from Sihe Mine in Shanxi Province was selected as the substrate,and the func-tional microbial agent was added to carry out the microbial anaerobic degradation of coal-driven gas desorp-tion experiment.The pore structure development and crystal structure evolution characteristics of coal before and after microbial degradation and metabolism were characterized by mercury intrusion experiment,low temperature N,adsorption experiment and X-ray diffractometer experiment.Research had found that after mi-crobial degradation,on the one hand,the pore volume and specific surface area of coal micropores,transition pores,mesopores decreased,the pore volume and average pore size of macropores were significant-ly improved,the pore structure of coal was obviously developed.On the other hand,the crystallinity of coal is reduced,the internal crystal structure becomes loose,and the arrangement between macromolecules be-comes more disordered.These show that the coal can achieve the effect of increasing permeability after the degradation of functional microorganisms,and the adsorption capacity is reduced,thus promoting the rapid desorption of gas in the coal body.