Effect of Municipal Solid Waste Incineration Fly Ash Addition on the Iron Ore Sintering Process, Mineral Phase and Metallurgical Properties of Iron Ore Sinter

摘要

Municipal solid waste incineration (MSWI) fly ash is well known as hazardous waste, for promoting its harmless treatment and resource utilization, a new process was proposed by utilizing the iron ore sintering process employed massively in iron and steel industry. In this article, the feasibility of this process was estimated from the point of the effects of MSWI fly ash addition on the iron ore sintering process, sinter mineral phase structure and metallurgical properties through the sintering pot experiments, the reduction and melt-dropping experiments at different temperature. Results show that, for the sintering process, the flame front speed, the sinter productivity, the drum index and the yield of sinter decrease with the increasing of MSWI fly ash addition; for the sinter metallurgical properties, with the increasing of MSWI fly ash addition, the lower temperature reduction property (RDI) is improved obviously, the soft-dropping property is worsened; but the effect of MSWI fly ash addition on the middle temperature reduction property (RI) is not obvious; for the sinter mineral phase, the phase fraction of the silico-ferrite of calcium and aluminum (SFCA) and the calcium silicate (CS) both increases with the increasing of MSWI fly ash addition. The complex of oxides, silicates and chlorides with lower melting point in the MSWI fly ash change the formation of sinter mineral phase and its composition essentially, which further effect the sintering process and the metallurgical properties.