Technological Advances and Trends in the Multi−Pathway, Coordinated, High−Value Utilization of Coal Gangue Toward Zero−Waste Objectives

Coal gangue is a typical large−scale solid waste generated during coal mining and processing. It embodies both resource potential and environmental burden. Its efficient and sustainable utilization has emerged as a critical approach for promoting green transformation of mineral resources and ensuring ecological safety. In alignment with the goal of zero−waste development, this study provides a comprehensive review of the current research landscape and technological advancements in the high−value utilization of coal gangue through multiple pathways. The discussion focuses on four principal valorization directions: construction materials, chemical extraction, energy recovery, and ecological applications. For each pathway, the underlying transformation mechanisms, key technologies, and industrial application status are systematically examined. Based on these insights, the study proposes an integrated utilization model featuring coordinated energy–chemicals recover–materialsy, and develops representative multi−path co−processing schemes to explore synergistic mechanisms and optimization strategies. Furthermore, a life cycle assessment approach is employed to quantitatively evaluate the carbon emissions, energy consumption, and environmental performance of various utilization routes. The results demonstrate that integrated utilization pathways offer significant advantages in terms of resource efficiency and environmental compatibility. Finally, from the perspectives of policy support, technical standards, economic feasibility, and regional coordination, the study analyzes current industrialization constraints and offers targeted recommendations—such as establishing a graded resource utilization framework, promoting modularized integration of utilization routes, and enhancing green performance incentive mechanisms. This research provides the theoretical foundations and practical guidance for the efficient transformation of coal gangue, multi−pathway synergy, and the advancement of green mineral engineering.