Cause, countermeasures and solutions of water hazards in coal mines in China

In the new century, the coal industry has experienced a decade of rapid development, and the coal output has been stabilized at about 4.5 billion tons. The coal mine safety situation is generally good, with the multiple, frequent and even catastrophic accidents reduced, the major accidents at sometimes developed to be single and occasional, and the extraordinarily serious accidents were controlled effectively. Water hazard of mine is still the main type of coal mine hazards in China, and it is the second largest lethal reason after gas hazard. The analysis shows that the complex mining environment and the insufficient attention are the main reasons for the accident. The main technical reasons for the accident include the failure of three levels of protection, such as the exploration of hydrogeological conditions of mine field, the exploration and treatment of hidden hazards, and the identification of water inrush signs. Accordingly, three technical measures were proposed, detect and release water to eliminate the hidden hazards, identify the abnormal conditions, and evacuate in time according to the regulations. Meanwhile, the procedure of “investigation, design, construction and evaluation” for advanced water detection and release was standardized. In addition, it was emphasized that the exploration theory and technology system and the water control system with the corresponding latest progresses, as well as the intelligent accurate perception and identification technology, formed a good foundation for preventing risks. Looking forward to the future, the theoretical exploration of deep learning, intelligent perception and up-scaling methods and other theoretical explorations, as well as the breakthrough of “3D transparent geological model” and its properties characterization technology, is the fundamental way to solve the randomness of geological body, the time variability of fluid and the dynamic nature of mining activities, which could achieve the ultimate goal of mine water prevention and control in China.