磷石膏流化分解过程颗粒的黏附特性

磷石膏热分解制硫酸联产水泥过程中在回转窑部分很容易由于颗粒的团聚和壁面黏附,造成管道堵塞,这样会严重影响磷石膏热分解制硫酸联产水泥的工艺运行.经过对比流态化分解磷石膏后的结垢物和流化粉末的X射线荧光光谱、X射线衍射和扫描式电子显微镜分析研究磷石膏热分解过程中的黏附变化.结果表明,结垢物中的Si、Al等矿物质元素明显高于流化粉末,说明主要的黏土性矿物质杂质在壁面黏附富集;随着反应的进行,CaO的含量的增加会较为明显的降低颗粒的黏附程度.因此对于磷石膏粉体,SiO2、Al2O3等杂质不仅影响磷石膏的分解效率,还严重影响其流化过程中的团聚黏附.

Adhesion Characteristics of Particles in Fluidized Decomposition Process of Phosphogypsum

During the production of sulfuric acid integrated with cement from phosphogypsum, it is common to have wall adhesion in rotary kiln because of particle agglomeration, blocking the pipeline and thus the operation.By comparing the profiles of XRF, XRD and SEM of the deposit and the fluidized powder change of adhesion during the thermal decomposition of phosphogypsum were investigated.The results show that the Si-containing and Al-containing mineral level in the deposit substance are higher than those in the fluidized powder, indicating adhesion and enrichment of most clay mineral impurities on the wall.As the reaction proceeded, increasing calcium oxide content markedly eased particles' adhesion.Thus it was suggested that, for phosphogypsum power impurities like SiO2 and Al2O3 not only affected the decomposition but also severely influenced the agglomeration and adhesion of the particles during the fluidization process.