Reusing Desulfurization Slag in Cement Clinker Production and the Influence on the Formation of Clinker Phases

The purpose of this study was to investigate the reuse of desulfurization slag in cement clinker production and its influence on the formation of clinker phases. The desulfurization slag that mainly contained Ca and Si was identified as non-toxic, and thus it should be suitable to be reused in clinker production. The addition of desulfurization slag increased the melt phase during clinkerization, but the excess melt phase inhibited the formation of clinker phases. This could be attributed to the sulfur and fluoride derived from the De-S slag. At low desulfurization slag addition (5.4 wt %), the resulting clinker had a mineralogical composition similar to that of the reference clinker. The desulfurization slag added can lower the clinkerization temperature and increase the amount of Ca3SiO5 at 1300 ◦C, which may be beneficial to energy conservation in clinker burning. Moreover, reusing desulfurization slag additionally has the potential to reduce the energy needed for clinker grinding.