Summary and prospect of open-pit coal mining technology in China

In the past 40 years of reform and opening up, China's open-pit coal mining technology has developed rapidly. Based on the latest information on China's open-pit coal mining technology and the National Coal Energy Production Capacity Announcement of the National Energy Administration in 2019, the development status of open-pit coal mines in China is summarized from the aspects of scale, quantity, capacity, distribution and development subjects. It is characterized by its small capacity, large size and high development concentration. This paper summarizes the advanced mining technology of open pit mines from six aspects: basic theory, mining technology, equipment level, information intelligence, safety production and ecological restoration. At the same time, the study results of stripping ratio, slope instability and green mining are also described. The current mining technology is applied to the status of new technologies in the areas of coordinated mining, transportation optimization, high-efficiency blasting, and steep-end mining. The development and application of equipment, transportation and other equipment, localization and large-scale technology are analyzed, and the application is developed and applied. A total of 6 sets of information intelligent systems, such as truck intelligent dispatch, CI-IDS Production Management, tire life management, dewatering intelligent drainage, intelligent blasting are developed and four major safety aspects of slope landslide, transportation accident, small coal mine gob collapse, water damage are summed up. From the aspects of green development, ecological restoration, comprehensive remediation, recovery and integration, landform reconstruction, dry fog and dust suppression, the paper summarizes the technical achievements of green mine construction, and combines the current reality to propose seven problems: the policy and development are not synchronized; the mining mode is relatively single; the mining technologies are unbalanced; large-scale key equipment and spare parts still rely on imports; high-efficiency open-pit mining technology is less applied; the technology to restore ecological originality is still immature and the major disaster management technologies still need to break through. Finally, five new understandings have been put forward on the development of high-quality and intelligence of open-pit coal mines in China: exploring multiple pits in open pit mines, developing new models for joint development of underground and open-pit mining, developing mining shovel, unmanned trucks, large crushers, and other high-end intelligent equipment to support the construction of smart mines, innovating to guarantee the safe and efficient production of human-machine safety, creating a complete set of green mining technology systems for green mining, damage identification and original restoration, as well as establishing a professional operation team and training professional mining personnel in order to accelerate the realization of the high-quality development of China′s coal industry.