Research progress in coal and gas co-mining modes in China

Abstract

High gas mines and outburst mines contribute to more than 30% of the coal production capacity in China. In view of this, coordinating the development and use of coal and gas has become an urgent concern for China's coal industry. After years of efforts, the concept of a co-mining mode for coal and gas in China has gone through many stages, including theoretical discussion, engineering application, and assumption of concepts. Three modes have been gradually developed: the Huainan mode, based on pressure relief co-mining of a protective layer; the Jincheng mode, based on directional long borehole co-mining; and the YangQuan/SongZao mode, based on cross-layer borehole co-mining. These modes provide strong direction and the impetus to solve current predicaments and challenges of coal mining in China. Under the concept of “green” extraction and the corresponding urgent needs for environmental protection, high efficiency, and energy-saving extraction, experts and scholars in the coal industry are also exploring development trends for coal in the future. For example, researchers have suggested idealized mining methods for replacing traditional mining methods, including fluidized mining technology, intelligent unmanned mining technology, precision mining technology, green development of abandoned mines technology, and mining based on other technical means.