Green Process Practice of Cross Industry Hazardous Wastes Applied in Steelmaking and Refining

Utilizing the extremely high surface energy characteristics of micro particles in aluminum ash powder, a hazardous waste product from the aluminum industry, and polycrystalline silicon, a hazardous waste product from the photovoltaic industry, as well as the composition characteristics of reducing oxides in Al and Si, for the first time in the domestic steel industry, the KR fluorine-free hot metal desulfurization process based on aluminum ash powder flux was developed to replace the traditional KR desulfurization process with fluorite flux in the hot metal desulfurization process, and to avoid environmental pollution caused by fluorite. And the LF furnace rapid reduction top slag process based on polycrystalline silicon cutting powder pressing ball was developed to replace the traditional carbide reduction top slag process, and to avoid the safety hazards of carbide hazardous chemicals. The industrial test results show that the average addition amount of KR fluorine-free desulfurizer based on aluminum ash powder flux is 2 310 kg/furnace, which is equivalent to the KR desulfurizer amount of traditional fluorite flux. The average sulfur mass fraction of hot metal before and after desulfurization is 0.023 0%, 0.003 1%, and the average desulfurization rate is 86.52%. The LF furnace rapid reduction top slag process based on polycrystalline silicon cutting powder pressing ball has a fast slagging speed of white slag, and the mass fraction of (TFe+MnO) in ladle slag is stable at less than 1.0%, and the heating rate of the refining process is comparable to that of traditional processes. Process practice has shown that the cross industry application of hazardous waste such as aluminum ash powder and polycrystalline silicon cutting powder in steelmaking and refining not only solves the problem of recycling aluminum ash powder and polycrystalline silicon cutting powder, but also promotes the industrial development of green steelmaking.