The evolution of thick coal seams mining methods in China

The article provides an overview of the methods for developing thick coal seams in mines in China over the past decade. It is shown that the main methods used in China for coal mining from thick seams at the moment are two methods — the Complex mechanized method of developing seams at their full capacity (used only in simple geological conditions and is an additional method for the following) and Complex mechanized mining method with coal production (which is used mainly, including in difficult conditions). Despite the fact that these methods have positively proven themselves over the years, their use has a number of significant drawbacks, including a low extraction rate, an increased risk of endogenous combustion and rock burst, and others. To solve the problems of a low extraction rate and to maintain preparatory workings, the Chinese miners managed to develop a successful solution in which a ventilation drift is carried out in cross section to the worked out space or under collapsed rocks. At the same time, for the widespread application of this solution, further research is necessary. Currently, a promising way is a development method with a diagonal (cross-shaped) arrangement of drifts, which helps to eliminate many of the shortcomings of previous methods, including a low recovery coefficient, the risk of spontaneous combustion, the need to support the drift and others. It is expected that this method will be widely used for underground coal mining in deep mines in China with difficult mining and geological conditions.

Qiao Jianyong, Wang Zhiqiang, Zhao Jingli The evolution of thick coal seams mining methods in China. MIAB. Mining Inf. Anal. Bull. 2020;(8):105-117. [In Russ]. DOI: 10.25018/0236-1493-2020-8-0-105-117.

Qiao Jianyong^1,2, Dr. Sci. (Phys. Mathem.), Professor, Rector, Foreign Member of Russian Engineering Academy,
Wang Zhiqiang¹, Doctor of Mining Engineering, Assistant Professor, e-mail: wzhiqianglhm@126.com,
Zhao Jingli¹, Cand. Sci. (Eng.), Professor, Foreign Member of Russian Engineering Academy,
¹ China University of Mining and Technology (Beijing), Beijing, China, 100083,
² Beijing University of Posts and Telecommunications, Beijing, China, 100876.

Wang Zhiqiang, e-mail: wzhiqianglhm@126.com.

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