Abstract: The chemical and mineral composition, physical and chemical properties of electrolytic manganese slag and magnesium slag were first analyzed by chemical analysis, X-ray diffraction (XRD), scanning electron microscopy (SEM) and thermogravimetric analysis (TG-DSC), respectively.Based on the analysis results, the formulas of sulphoalu minate cement clinker were rational designed using the two types of slag as part of raw materials.Then the effect of sintering temperature on the properties of the clinker was investigated.After adding gypsum into the clinker, the early strength, rapid hardening sulphoalu minate cement was formed.During the heat of hydration, the effect of gypsum content on the compressive and flexural strength of the cement were examined, and the optimum gypsum dosage can be determined.The experimental results show that the electrolytic manganese slag and magnesium slag can be used as valuable raw material for preparation of sulphoalu minate cement clinker.With the two slags of 21% and 21%, respectively, the composition of sintered clinker are mainly C2S and C4A3S-after being treated at 1260 ℃ for 30 min.The optimal mechanically properties of the prepared cement are achieved with 28 d flexural strength of 5.1 MPa and compressive strength of 31.2 MPa when 15% gypsum is added in the clinker.The impermeability grade reaches P6, and the clinker and hydration product can solidify the heavy metal effectively, which can not be leached easily.

Key words: electrolytic manganese slag;magnesium slag;sulphoaluminate;cement clinker