Process to utilize crushed steel slag in cement industry directly: Multi-phased clinker sintering technology

To improve the utilization efficiency of steel slag in cement industry, cement clinkers are prepared by simulated multi-phased clinker sintering technology with crushed steel slag (without grinding). The results show that after high temperature treatment, the inert components and tough phases of steel slag such as iron phase, calcium ferrite phase and RO phase (CaOFeOMnOMgO solid solution) are reduced; the soundness, grindability and hydration activity of steel slag can be certainly improved; hydration activity of the multi-phased cement at early age is a little lower than that of grade 42.5 ordinary Portland cement, while develops faster than later. The multi-phased cement clinker prepared at 1400 °C with the raw material contains 16.86% steel slag has comparable grindability and soundness to the normal Portland cement clinker. Compared to traditionally using steel slag as a cement raw meal, the multi-phased clinker sintering technology has much greater technical and economic advantage. It is a promising approach to the extensive utilization of steel slag in cement industry.