关键词: 煤基固废, 煤气化细渣, 综合利用, 残碳, 矿物加工方法

Abstract: Coal gasification is the key basis of low-carbon and clean utilization of coal, but the discharge of fine slag solid waste has become an important factor restricting its development, which needs to be dealt with cautiously through reasonable, efficient and clean comprehensive utilization means. The production mechanism and main characteristics of fine slag are introduced in this paper. The recent research progress of fine slag in building materials (cement, building bricks, wall materials, concrete), high value-added materials (silicon-based mesoporous materials, carbon-silicon com-posites, sialon ceramics, adsorption materials) and combustion are reviewed. It is pointed out that the residual carbon and the amorphous silicon and aluminum oxides in fine slag are the material basis for resource utilization and high value-added utilization of fine slag, and then the value and importance of pre-carbon ash separation for high value and deep processing and utilization of fine slag are analyzed. The effects of foam flotation, gravity separation and sieving (classification) on carbon-ash separation of fine slag are discussed, and it is pointed out that the fine particle size distribution, high porosity structure, and the mutual intercalation, melting and coating between residual carbon and ash are the main factors leading to the difficulty of comprehensive utilization, high processing cost and large-scale utilization difficulty of fine slag. Based on the existing re-search and application practice, it is put forward that optimizing the coal gasification process and corresponding equipment, improving the carbon conversion efficiency as much as possible and reducing the enrichment of residual carbon in solid residue are essentially the ways to solve the problem of treatment and disposal of fine slag. For the stock problem, it is appropriate to adopt clean, environmentally friendly, low-cost landfill technology, soil remediation technology, building materials technology and other large-scale verification methods. In addition, the high efficiency separation technology and the high performance materials preparation technology should be verified by further scientific research and demonstration, and their utilization scope should be expanded by means of policy and market guidance, so as to realize the development of related advantage technology from laboratory to industrialization, and finally solve the problem of treatment and disposal of fine slag.