Investigation on industrial trial production of multi-phased clinker with crude granular steel slag

Steel slag multi-phased clinker implemented trial production in cement plant for the first time, which provided an effective low carbon strategy for comprehensive utilization of granular steel slag to produce high quality cement clinker. The results show that through optimizing process parameter of cement kiln system, superior qualified clinker was produced stably along with a river of granular steel slag fed in the smoke chamber directly. The grindability of steel slag has been dramatically improved after clinkerization. The content of C3S and C4AF in multi-phased clinker was higher than that of general clinker and thereby improving the mortar strength. Moreover, the multi-phased clinker showed significant improvement on abrasive resistance. The application of steel slag multi-phased sintering technology in a 2500 t/d production line could result in comprehensive utilization of 72368.4t granular steel slag, 67163.3t of CO2 emissions reduction and economic benefits of 15.21 million RMB every year. Multi-phased clinker process is a breakthrough on crude steel slag utilization from the bottlenecks of soundness, grindability and hydration activity of steel slag. The industrial trail of producing higher quality clinker from granular steel slag without grinding and sieving provides a new approach to utilize steel slag directly with extraordinary economic and environmental benefit.