Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

Journal

Environmental Sciences

2023

Gas extraction

Articles 1 - 3 of 3

Full-Text Articles in Physical Sciences and Mathematics

Numerical Simulations Of Enhancing Permeability And Gas Extraction Of Thick Coal Seams Through Static Fracturing, Wang Xinfeng, Liu Wengang, Wang Long, Wei Youyu, Zhang Qiao Nov 2023

Numerical Simulations Of Enhancing Permeability And Gas Extraction Of Thick Coal Seams Through Static Fracturing, Wang Xinfeng, Liu Wengang, Wang Long, Wei Youyu, Zhang Qiao

Coal Geology & Exploration

This study seeks to improve the underground operation efficiency and optimize the borehole arrangement parameters for static fracturing of coal seams. To this end, this study conducted tests in the belt roadway of the No. 12316 fully mechanized mining face in the Wangjialing Coal Mine, China Coal Huajin Group. By combining the equations for coal seams’ deformation and failure, gas diffusion and seepage, and coal seams’ permeability evolution, this study constructed a model of the damage and permeability evolution of coal seams. Based on the numerical simulations of the process of static fracturing and permeability enhancement of coals, as well …


Research On Three-Stage Automatic Hole Packer For Gas Extraction Drilling In Underground Coal Mine, Wang Qingfeng, Shi Shuhan, Xin Dezhong, Chen Hang, Zhang Shitao Sep 2023

Research On Three-Stage Automatic Hole Packer For Gas Extraction Drilling In Underground Coal Mine, Wang Qingfeng, Shi Shuhan, Xin Dezhong, Chen Hang, Zhang Shitao

Coal Geology & Exploration

In view of the requirements of hole sealing during gas extraction drilling in underground coal mine for manual packer installation and sealing material injection, as well as the low automation level of hole sealing technology, a three-stage automatic hole packer for gas extraction drilling in underground coal mine was developed, with the appearance similar to the drill pipe. The hole packer could be mechanized into the drilling hole by an automatic drilling machine, and realize the automatic injection of sealing material. Herein, the Mooney-Rivlin hyperelastic constitutive model was used to represent the strain energy function by the finite element analysis …


Current Situation And Development Trend Of Pressure-Relief Gas Extraction In The Protective Layer Mining In Coal Mines In China, Xue Junhua, Xiao Jian, Du Xuanhong, Shi Yu Jun 2023

Current Situation And Development Trend Of Pressure-Relief Gas Extraction In The Protective Layer Mining In Coal Mines In China, Xue Junhua, Xiao Jian, Du Xuanhong, Shi Yu

Coal Geology & Exploration

Deep coal mining in China is seriously restricted by factors including high stress, high gas pressure, and low coal seam permeability. Moreover, with the gradual deterioration of the mining conditions of deep coal seams, it is increasingly difficult to control the gas in these coal seams. Fortunately, the pressure-relief mining of protective layers serves as an efficient way to control gas and eliminate coal and gas outbursts. To meet the demand of practical projects, this paper reviews the studies on the mining technology for protective layers, the law of change in the stress of protected layers, the evolutionary law of …