惰性气氛下电解锰渣高温还原焙烧脱硫

Removal of sulfur from electrolytic manganese slag by high-temperature reduction roasting in an inert atmosphere

电解锰渣的化学成分与水泥的组成符合,但高含硫量限制了其在水泥生产中的掺量。本研究采用高温还原焙烧法脱除电解锰渣中的硫,以焦炭为还原剂,在氮气气氛中以不同条件对电解锰渣进行热分解生成SO_(2)。用扫描电镜(SEM)和X射线衍射(XRD)分析固体产物,气体分析仪分析SO_(2)的释放,高温还原焙烧法脱除电解锰渣中的硫,探究焙烧温度和焦炭添加量对焙烧产物的物相和硫含量的影响。实验结果表明,生成SO_(2)的最佳条件为焦炭添加量4%、分解温度1000℃。在最佳条件下,SO_(2)的最大浓度为3513mg/m^(3),可用于生产硫酸。焙烧固体产物在温度为900℃、焦炭添加量为4%添加时,SO_(3)含量可以降低到2.17%。根据GB175—2007《通用硅酸盐水泥》中规定,满足水泥中SO_(3)含量须低于3.5%的要求,电解锰渣还原焙烧产品可以作为水泥原料,为电解锰渣的资源化综合利用提供理论依据和技术参考。

The chemical composition of electrolytic manganese slag is required to have good consistency in the composition of cement,but the high sulfur content limits its mixing in cement production.In this study,coke was used as the reducing agent,and the electrolytic manganese slag was thermally decomposed to generate SO_(2)under different conditions in a nitrogen atmosphere.The solid product was analyzed by SEM and XRD.The gas analyzer analyzed the release of SO_(2).The high temperature reduction roasting method was used to remove the sulfur in the electrolytic manganese slag.The effect of roasting temperature and coke addition on the phase and sulfur content of the roasted product was explored.Experimental results show that the optimal conditions for generating SO_(2)are 4%coke addition and a decomposition temperature of 1000℃.Under the best conditions,the maximum concentration of SO_(2)is 3513mg/m3,which can be used to produce sulfuric acid.When the temperature of the calcined solid product is 900℃and the coke addition is 4%,the SO_(3)content can be reduced to 2.17%.According to the provisions of GB175—2007“General portland cement”,the SO_(3)content in cement must be less than 3.5%,and the electrolytic manganese slag roasted product can be used as a cement raw material.It proves the feasibility of electrolytic manganese slag as a cement additive, and provides a theoretical basis and technical reference for the comprehensive utilization of electrolytic manganese slag.