Case study of utilizing steel slags as raw material in clinker production

The use of iron and steel slags of different origins as potential raw materials in the making of Portland clinker is a prominent solution for their utilization. Iron and steel making slags quite resemble to the cement clinkers as all of them are composed of different kind calcium silicates, aluminates and other multiple phases containing iron. Moreover, slags being a by-product of pyro-metallurgy process, those are calcined material. Hence unlike other conventional raw materials of clinkers (limestone, clay etc.) those do not cause mass loss during clinkerization process at high temperature (~1450 °C). Such slags can effectively supplement raw meal chemical composition. The current work has explored different compositions of clinker raw meals by utilization of iron and steel making slags with replacement/reduction of raw materials from natural resources. Lab-scale burnability study for clinker making followed by detail characterization, including physical property analysis, chemical analysis, phase analysis, microscopy and heat of hydration has been conducted. The resultant clinkers have exhibited superior quality. Hence, this work has demonstrated an efficient and sustainable approach for circular economy and conservation of natural resources.