Abstract:
As the core carrier for realizing the construction of green mines and co-disposal of industrial solid wastes, solid waste-based cemented paste backfill (SCPB) technology has become a hot research topic in the field of mining engineering in terms of material design and performance regulation. Aiming at the problem of discrete performance of SCPB caused by the significant difference in physical and chemical properties of industrial solid wastes from multiple sources (waste rock from mining, tailings from mineral processing, metallurgical slag, chemical wastes, etc.), the differences in the roles of solid wastes from multiple sources in the backfill materials and the comprehensive performance of different SCPB in terms of rheology, strength, and environmental aspects are systematically reviewed. It mainly includes: A systematic review was conducted on the sources, properties and uses of different SCPB. It was found that the chemical components of typical industrial solid wastes (tailings, steel slag, fly ash, etc.) exhibit significant complementarity, and the gradient distribution of SiO
2, CaO, and Al
2O
3 provides a material basis for synergistic coagulation; The rheological properties, calculation of pipeline resistance, strength distribution and optimization means of different SCPB were systematically summarized, and the distribution ranges and laws of the yield stress, viscosity and compressive strength of SCPB were analyzed. It was found that the composite control of particle size grading optimization and polycarboxylate water reducing agent can effectively reduce pipeline transportation resistance. Selecting appropriate activator and auxiliary cementitious material ratios can effectively improve the strength of the SCPB; This study evaluated the environmental pollution risk of SCPB in different time scales, systematically sorted out the leaching mechanism and solidification mechanisms of harmful elements in SCPB, and summarized the current situation of mine backfill pollution control. It was found that improving the hydration reaction process of SCPB and adding porous materials can effectively control the diffusion of pollutants. The research results are of great significance in promoting the sustainable development of the mining, processing, metallurgy and chemical industries, alleviating the pressure of solid waste disposal, improving the comprehensive utilization rate of resources and promoting the construction of green mines.