Abstract:
Underground coal mining generates substantial amounts of coal gangue, which not only consumes limited underground transportation and hoisting capacity while increasing production costs, but also risks causing environmental issues such as soil contamination and water body degradation, thereby constraining the sustainable development of the coal industry. The practice of in-situ gangue disposal—a green mining method that promotes the integrated advancement of on-site gangue disposal, resource recycling, and ecological conservation—is gradually emerging as a key technology for the transformation of coal mining toward greener, smarter, and more efficient operations.This study survey focuses on recent developments in technologies and equipment for in-situ gangue disposal. It systematically examines the current status and challenges facing key processes such as the underground separation of raw coal from gangue, as well as the crushing, transportation and utilization of gangue. Firstly, by examining the current state of gangue management, national governance policies, and the value of gangue, the survey elucidates the necessity and strategic significance of in-situ disposal of gangue underground.Secondly, the research analyses the development of technologies and equipment used in the separation, crushing, transportation, and utilization of in-situ gangue disposal. Finally, the research outlines the end-to-end process for in-situ gangue disposal, based on the “separation-crushing-transportation-utilization” approach: underground intelligent dry separation, multi-stage gangue crushing, long-distance underground pneumatic transportation, and comprehensive utilization of gangue. It summarizes the exploratory practice regarding the integrated equipment for “separation - crushing - transportation -utilization” of coal gangue underground. The findings will provide theoretical support and technical frameworks for the green and low-carbon transition and efficient mining operations in China’s coal mines.