Recycling and product chain of coal-based solid waste

Abstract

Large-scale recycling of coal-based solid waste has important practical significance for the sustainable development and ecological environment protection of the large-scale energy bases in northwestern China. In this study, the typical energy bases in northwestern China were taken as a research object. The principle of collaborative location of solid waste and industry in the region was applied in the analysis. Key technologies such as the use of coal-based solid waste to produce chemicals, environmental protection materials, and building materials were proposed. The key product chains of typical coal- based solid waste recycling such as calcium carbide slag, gasification slag, and spent catalysts were established. The results show that coal- based solid wastes such as calcium carbide slag, gasification slag, and spent catalyst can be used to prepare desulfurizers, water glass, catalysts, and other products with good performance through separation of impurities, phase control, and catalyst carrier refactoring. The products can be directly used in the production process of coal-electricity-chemical enterprises in the region. In the coal-based solid waste 90% of calcium, aluminum, and silicon can be effectively used, and the recycle rate of vanadium, wolfram, and titanium can reach over 90% . Residual carbon can be separated. The utilization efficiency of coal and water resources of the recycling product chain can be increased to 36% and 27%, respectively, which can reduce the emissions of three types of typical solid waste by more than 98%. The process can provide a new way for large-scale utilization of solid waste, and can realize the high efficiency utilization of coal and secondary resources in coal energy bases.