Permeability model and gas migration law of filling gangue by roof cutting along the gob in a coal mine: A case study

Jinzhao  Liu; Dongyin  Li; Xiangjun  Chen; Shen  Wang

doi:10.6180/jase.202409_27(9).0002

Permeability model and gas migration law of filling gangue by roof cutting along the gob in a coal mine: A case study

Jinzhao Liu¹This email address is being protected from spambots. You need JavaScript enabled to view it., Dongyin Li^1,2, Xiangjun Chen^2,3, and Shen Wang^1,2

¹School of Energy Science and Engineering (Henan Polytechnic University), Jiaozuo 454003, China

²State Collaborative Innovation Center of Coal Work Safety and Clean-efficiency Utilization, Jiaozuo 454003, China

³College of Safety Science and Engineering (Henan Polytechnic University), Jiaozuo 454003, China

Received: March 16, 2023
Accepted: August 4, 2023
Publication Date: December 3, 2023

Copyright The Author(s). This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are cited.

Download Citation: ||https://doi.org/10.6180/jase.202409_27(9).0002

The roof falls into the gob at the end of the working face due to the technique of roof cutting along the gob. The greatly decreased void will lead to serious changes in the airflow. This study established and validated a gob permeability model under roof cutting along the gob conditions. The results show that the falling gangue after roof cutting is filled to the gob in an overfilled state, resulting in a significant reduction in the void at the side of the air inlet roadway. Air flow has the effect of significantly shrinking the oxidation zone of the heat dissipation zone in the gob, causing the gas emitted from the gob to accumulate in the middle and deep of the gob and ultimately increasing the high-level gas extraction roadway by 19.3 percent.

Keywords: Roof cutting along gob; void; Permeability; Gas flow law

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