Characteristics of Cement Raw Mix and Clinker used Non-Carbonated Materials

The cement industry emits a large amount of GHGs (greenhouse gases) and about 65% of GHGs is originated from limestone. So non-carbonated CaO materials were examined to replace limestone in this study. It was attempt to replace limestone by used blast furnace slag, converter slag, and KR slag with high CaO content. For manufacture clinker, LSF, SM, and IM were controlled at 92, 2.5, and 1.6, respectively, and the CaCO3 replacement rate was fixed at 3%, 6%, 9%, and 12%. As using blast furnace slag, the CaCO3 replacement rate was possible up to 12%, but for converter slag and KR slag, up to 3% and 9% were possible. The burnability of clinker was better when blast furnace slag and KR slag were used. The XRD peak intensity of clinker used blast furnace slag gradually decreased as the amount of slag used increased, but when KR slag was used, the XRD peak intensity actually increased. It was presumed to be because KR slag has a high CaO content and already contains C2S, making it easier to produce clinker minerals.