Current Status of Research on Fill Mining Systems

Background: With the rapid development of society, the demand for coal in production and daily life has been growing at an unprecedented rate. However, extensive coal mining has led to various environmental and safety issues. The gradual depletion of shallow mineral resources, the increasing depth of mining operations leading to more challenging mining environments, the severe pollution caused by the accumulation of large amounts of mining waste on the surface, and the continuous emphasis on green, environmentally friendly, and sustainable development concepts have necessitated effective solutions. In response to these challenges, the adoption of backfill mining technology has emerged as a viable approach. Objective: This paper offers a comprehensive overview and classification of the methods and mechanical systems utilized in backfill mining within coal mines. It provides a succinct explanation of the implementation of diverse backfilling methods in mining activities and the present state of various backfilling mechanical systems. This information can assist researchers and businesses in understanding the evolution of filling technology and serve as a crucial foundation for future research and innovation. Methods: An evaluation of Backfill Mining Method Patents and Backfill Mechanical System Patents and an Introduction to the Advantages and Disadvantages of Different Backfill Methods have been analyzed. Results: Through the analysis and comparison of existing backfill methods, we can summarize the typical characteristics of each technique. Finally, we discuss the future development trends of backfill mining. Conclusion: Backfill mining can effectively support rock strata, control ground pressure activity, and protect surface flora and fauna. It can also improve the stress state of mining pillars and maximize resource recovery. Furthermore, it enables efficient handling of solid waste, reduces production costs, and achieves green and sustainable development. Each backfill mining system has its advantages and disadvantages, therefore, it is necessary to consider multiple factors comprehensively in order to choose the appropriate method.