锰渣及锰渣陶粒热机理研究

Study on the Thermal Mechanism of Manganese Slag and Manganese Slag Ceramsite

利用锰渣复配粉煤灰与硅藻土制备陶粒,对锰渣与锰渣陶粒热机理进行探究。根据其热分析数据进行梯度烧结,并进行X射线衍射(XRD)与扫描电镜-能谱仪(SEM-EDS)表征。XRD与SEM-EDS测试结果表明,锰渣主要成分为二水石膏(CaSO_(4)·2H_(2)O)和石英(SiO_(2)),烧成后锰渣陶粒主要成分为钙长石(CaO·Al_(2)O_(3)·2SiO_(2))和石英。在烧结过程中,锰渣中石膏具有二水石膏、半水石膏(CaSO_(4)·0.5H_(2)O)、无水石膏(CaSO_(4))三种晶体形态,CaSO_(4)最终分解为CaO与SO_(3)气体。陶粒烧成时表面液相包裹SO_(3)气体形成陶粒气孔,钙长石是CaO与SiO_(2)、Al_(2)O_(3)反应的产物。锰渣陶粒复配粉煤灰与硅藻土增加SiO_(2)质量分数,能提高石膏晶体转变和分解温度,进而提高烧成温度。本研究对锰渣资源化利用及锰渣陶粒的生产具有指导意义。

Manganese slag mixed with fly ash and diatomite was used to prepare ceramsite,and the thermal mechanism of manganese slag and manganese slag ceramsite was investigated.According to the thermal analysis data of manganese slag and manganese slag ceramsite,the manganese slag and manganese slag ceramsite were graded sintering and characterized by XRD and SEM-EDS.The XRD and SEM-EDS results show that the manganese slag is mainly composed of gypsum dihydrate(CaSO_(4)·2H_(2)O)and quartz(SiO_(2)),and the sintered manganese slag ceramsite is mainly composed of anorthite(CaO·Al_(2)O_(3)·2SiO_(2))and quartz.In graded sintering,gypsum in manganese slag has three crystal forms of dihydrate gypsum,hemihydrate gypsum and anhydrous gypsum.CaSO_(4) finally decomposes into CaO and SO_(3) gas,and the liquid phase on the surface of ceramsite wraps SO_(3) gas to form ceramsite pores.Anorthite is the product of reaction of CaO with SiO_(2) and Al_(2)O_(3).The mixture of fly ash and diatomite with manganese slag ceramsite increases SiO_(2) content,improves the crystal transition and decomposition temperature of gypsum,and then increases the sintering temperature.This study has guiding significance for resource utilization of manganese slag and production of manganese slag ceramsite.