Experimental study on gas emission from coal mass with a rich microstructure

Huan Zhang; Hongbao Zhao; Tao Wang; Yifan Huang

doi:10.3139/120.111329

Article

Experimental study on gas emission from coal mass with a rich microstructure

Huan Zhang , Hongbao Zhao , Tao Wang and Yifan Huang

Published/Copyright: March 26, 2019

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From the journal Materials Testing Volume 61 Issue 4

Abstract

Through a coal mass sample with a rich microstructure and a self-designed experiment using lump coal to determine the characteristics of gas emission, this paper analyzes gas emission in a coal mass with rich microstructure. The results show: The differences between raw coal and a briquette are mainly found in the scale and number of their microstructures. Nevertheless, the two samples share a high degree of similarity. The gas emission speed of a coal particle is higher than that of coal mass with a rich microstructure. The decay rate of gas emission speed also is confirmed as the same process. It takes longer for coal mass with a rich microstructure to reach the limit of its gas emission volume than for coal particles. Gas emission in a coal mass is a continuous process of gas desorption, migration and seepage. During the process, the coal mass reacts in four possible ways: coal mass immediately participating in gas emission, gradually participating in gas emission, providing a gas source for gas emission and as a non-affected coal mass. The relation between the gas emission speed of the coal mass with a rich microstructure and test time shows a monotone decrease in the power function, and the relation between the cumulative volume of the gas emission and the test time reveals a monotonically increasing logarithmic function. The gas emission for coal mass with a rich microstructure can be well expressed by modified logarithmics.

*Correspondence Address, Prof. Dr. Hongbao Zhao, State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, (Southwest Petroleum University), Chengdu 610500 P. R. China, School of Resource and Safety Engineering, China University of Mining and Technology, Beijing 100083, P. R. China, E-mail: hongbaozhao@126.com

Huan Zhang, born in 1991, is a Doctoral student of mining engineering at the School of Resource and Safety Engineering, China University of Mining and Technology, Beijing. He is mainly engaged in the research of coal and rock mechanics, gas control technology and has published several articles in this field.

Hongbao Zhao, born in 1980, is Professor and doctoral advisor. He is a Doctor of Mining Engineering and is mainly engaged in teaching and research coal and rock mechanics and gas control technologyand has made some achievements in this field. He works at the School of Resource and Safety Engineering, China University of Mining and Technology, Beijing, China.

Tao Wang, born in 1989, is a Doctoral student of mining engineering at the School of Resource and Safety Engineering, China University of Mining and Technology, Beijing, China. His research mainly focuses on coal and rock mechanics. He has published several articles in this field.

Yifan Huang, born 1992, is a Master's student of mining engineering at the School of Resource and Safety Engineering, China University of Mining and Technology, Beijing, China. He is mainly engaged in the research of coal and rock mechanics, gas control technology.

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Published Online: 2019-03-26

Published in Print: 2019-04-04

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https://doi.org/10.3139/120.111329