Dual extraction process increases mining safety

Workers inspect coalbed methane extraction equipment at the Yuecheng Coal Mine. ZHU YUANZE/FOR CHINA DAILY

Coal-bed methane used to be the No 1 threat to coal mine safety in Shanxi,but it's now expected to become a safe source of energy in large volume thanks to new technological achievements made by a local coal and coal-bed methane simultaneous extraction lab.

The Jincheng,Shanxi-based National Laboratory on Coal and Coal-Bed Methane Simultaneous Extraction,a research institute jointly founded by Jinneng Holding Group,China University of Mining and Technology and other research institutions,announced on Feb 19 a major breakthrough in its demonstration project at the Yuecheng Coal Mine in Qinshui county.

The coal mine and the lab's executives said the coal mine's YCCD-02 shaft reported a daily extraction volume of 37,900 cubic meters,a world record for coal-bed gas extraction in rubble areas of coal mines.

"Coal-bed methane is a kind of natural gas and clean energy source.However,it's also the top threat to coal mine safety,"said Wang Baoyu,deputy general manager of Jinneng Holding,who is in charge of the demonstration project at Yuecheng.

He noted that nearly 80 percent of coal mine accidents are related to coal-bed methane and the discharge of the gas from coal mines can lead to the increase of greenhouse gases in the atmosphere.

The executive said Yuecheng was chosen as the site of the simultaneous extraction research because it owns several high-methane-content shafts.

"We usually use horizontal slicing mining to extract coal,"Wang said."The process can lead to a difference in gas pressure in working and rubble areas,causing a threat to miners."

He noted that the simultaneous extraction of coal and gas can effectively solve the problem of high content of coal-bed methane in mines,increasing safety and developing a new source of energy.

The lab is a major move in Shanxi's transformation of its energy industry,according to provincial energy officials.

In recent years,Shanxi has invested a total of 1 billion yuan($155 million)in more than 100 research projects to develop new technologies and solutions for the transformation that features the gasification of coal and the development of coal-bed methane as fuel and chemical raw materials.

Jinneng Holding is one of the earliest coal mining enterprises engaged in the research of coal-bed methane.It has been leading in the sector in China since the early 1990s.

Wang Pei contributed to this story.

By YUAN SHENGGAO