Effect of rich-MgO from low-calcium limestone on the calcination and properties of C₄A₃$-C₂S clinker

Abstract

As one type of low-calcium cement, C₄A₃$-C₂S clinker consumes less energy and can utilize rich-MgO low-calcium limestone. The effect of rich-MgO low-calcium limestone on its calcination and properties is studied by means of f-CaO, XRD Rietveld refinement, TG-DTG and Lithofacies analysis. The results show that 3%∼5% MgO can promote the absorption of f-CaO and accelerate the formation of highly active monoclinic C₃S and C₄AF in clinker. When the MgO content is 7% and 8%, C₄A₃$-C₂S clinker calcined at 1380°C has excellent mechanical properties and its soundness is still qualified. This research shows that the rich-MgO low-calcium limestone can replace more than 50% of natural limestone to prepare C₄A₃$-C₂S clinker in cement industrial production.

Keywords

MgO / C₄A₃$-C₂S clinker / Early hydration / Compressive strength