磷矿石中杂质对磷酸生产的影响

Effects of impurities in the phosphate rocks on the phosphoric acid production

介绍了磷矿中水分,Ca O,Fe_2O_3,Al_2O_3,Mg O,酸不溶物及Cl-等杂质对磷酸生产过程的影响。随着磷矿中杂质含量上升,在磷酸浓缩过程中,会有大量的杂质结晶析出。杂质在管壁表面形成垢物,且增加了浓磷酸的黏度,使磷酸在石墨列管中流动变慢,严重影响磷酸运行周期。根据不断试验,技术人员采用分子量适中的有机絮凝剂聚丙烯酰胺对浓酸杂质进行处理。当使用聚丙烯酰胺质量分数在3.6‰~5.6‰时絮凝效果最佳。

Effects of impurities such as water,CaO,Fe2O3,Al2O3,MgO,acid insoluble and Cl- in the phosphate rocks on thephosphoric acid production process.With the increasing of the impurity content, massive impurity crystallized during the concentration ofthe phosphoric acid.The impurities formed sulfate scale on the surface of the tube wall and increased the viscosity of the concentratedphosphoric acid,which slowed down the flow of the phosphoric acid in the graphite tube and seriously affectedthe operation cycle of theplant.Based on the continuous experiments,polyacrylamide with a moderate molecule weight was chosen as the organic flocculant to treatthe impurities in the condensed acid by the technicians.The optimum concentration of the polyacrylamide was 3. 6‰-5. 6‰（wt）.