低浓度磷酸盐去除过程中的存在形态分析

Form of Phosphorus in Low Concentration Phosphorus Removal Process

水体中大量磷的存在会对环境和水生生物产生致命的危害,因此开发建立水体中低价磷的转化与去除关键技术显得刻不容缓。本文主要通过Visual MINTEQ软件对磷酸盐体系以及单金属盐除磷时反应体系的物相组分进行了模拟,发现磷酸盐在水体系中主要以HPO4^2-、H2PO^4-、H3PO4以及PO4^3-的形式存在,不过其含量则随着pH的变化而变化。另外利用金属盐沉淀法去除磷酸盐时,大量金属盐会自身水解形成相应的沉淀,少量组分会与磷酸盐反应生成沉淀达到除磷的目的,因此为了达到较好的除磷效果,所需要的金属盐会比理论值多。本文的实验结果为后续实验过程中操作条件的选择提供了重要的参考依据。

Large amount of phosphorus was harmful to the environment and aquatic life,thus research and build the conversion of low valence phosphorus and removal technology was needed.This paper focused on the simulation of phosphorus species in P-H2O system with Visual MINTEQ,the results showed that the phosphorus was existed as HPO4^2-,H2PO^4-,H3PO4 and PO4^3-,while the mole fraction was changed along the pH of phosphorus solution.In the phosphorus removal process with metal salts,the metal salts would hydrolyze and formed precipitation,some of it would react with phosphorus and generate precipitation lead to phosphorus removal.Thus,the dosage of metal salts was more than in theory in order to achieve high removal efficiency of phosphorus.The results could provide theory for the further experiment conditions.