基于膜分离的铁盐除磷效果影响因素

Influencing Factors of Ferric Salt for Phosphorus Removal Effect Based on Membrane Separation

文章以硫酸铁为化学除磷药剂,研究了其用于膜分离法化学除磷效果的影响因素,揭示了pH、Fe/P以及有机物浓度等因素对除磷效果影响机制,并得出当pH值在6.32~8.20、Fe/P为1.5时的除磷效果最优。进一步采用平板微滤膜元件作为过滤材料,探究了微滤膜对于铁盐溶液的截留作用以及对其除磷效果的影响机理。结果表明,微滤膜能够对颗粒态和胶体态的铁盐进行有效截留,而对于溶解态铁盐基本无截留作用。连续流过滤试验结果表明,生活污水中存在的细微颗粒或者絮体有利于铁盐水解形成絮体结构,并与水中的磷酸盐结合形成更大尺度的絮体结构或沉淀,在微滤膜的截留作用下被拦截在反应器内部,从而提高TP的去除率。

In this study,ferric sulfate was used as the chemical dephosphorization agent and the impact factor of chemical phosphorus removal effect for membrane separation.The effects mechanism of pH,Fe/P and organic matter concentration were investigatedi.It is concluded that the highest phosphorus removal efficiency was obtained when pH was in the range of 6.32~8.20 and ratio of Fe/P was 1.5.Furthermore,the interception function of microfiltration(MF)membrane on the retention of ferric salt solution and its phosphorus removal efficiency was also studied by using flat-sheet MF membrane as filter material.The results showed that the MF membrane can effectively intercept granular and colloidal ferric salt,while there was no interception on the dissolved ferric salt.The results of continuous flow filtration experiment showed that the fine particles or flocs in domestic wastewater were conducive to the hydrolysis of ferric salt to form floc structure,and combined with phosphate in water to form larger floc structure or precipitation,which is intercepted in the reactor under the interception of MF membrane,and thus improve the removal rate of TP.