China Safety Science Journal ›› 2021, Vol. 31 ›› Issue (2): 76-81.doi: 10.16265/j.cnki.issn 1003-3033.2021.02.011

• Safety engineering technology • Previous Articles     Next Articles

Study on temperature variation of coal sample in process of freezing coring

WANG Qiao1, WANG Zhaofeng1,2, Ma Shujun3, Zhang Kangjia1   

  1. 1 School of Safety Science and Engineering, Henan Polytechnic University, Jiaozuo Henan 454003, China;
    2 Ministry of Education Engineering Center of Mine Disaster Prevention and Rescue, Jiaozuo Henan 454003, China;
    3 School of Surveying and Land Information Engineering, Henan Polytechnic University, Jiaozuo Henan 454003, China
  • Received:2020-11-11 Revised:2021-01-17 Online:2021-02-28 Published:2021-08-18

Abstract: In order to explore change characteristics of coal sample temperature during process of freezing coring, a test equipment was designed independently based on similarity of simulation tests. Temperature change was measured under equilibrium gas adsorption pressure of 0, 1.0, 2.0 and 3.0 MPa respectively for samples of different metamorphism selected from Yujialiang Mine, Shoushan No.1 Mine, Liulong Mine and Jiulishan Mine. Then, real-time data of their temperature change during freezing coring was analyzed. The results show that the technology's freezing effect is positively correlated with coal metamorphism and gas adsorption equilibrium pressure. It has better freezing performance on coal with gas than non-gas coal, better on high metamorphic coal than on low metamorphic one. During freezing coring, change curve of coal sample temperature with time accords with exponential function.

Key words: freezing coring, temperature of coal sample, gas adsorption equilibrium pressure, coal metamorphism, coal seam gas content

CLC Number: