Effect of saline water ionic strength on phosphorus recovery from synthetic swine wastewater  

作　　者：Zhipeng Zhang Bing Li Filicia Wicaksana Wei Yu Brent Young 

机构地区：[1]Department of Chemical&Materials Engineering,University of Auckland,Auckland 1010,New Zealand

出　　处：《Journal of Environmental Sciences》2022年第3期81-91,共11页环境科学学报（英文版）

基　　金：This research was financially supported by the Department of Chemical and Materials Engineering,Faculty of Engineering,the University of Auckland。

摘　　要：Declining worldwide phosphate rock reserves has driven a growing interest in exploration of alternative phosphate supplies. This study involved phosphorus recovery from swine wastewater through precipitation of struvite, a valuable slow-release fertiliser. The economic feasibility of this process is highly dependent on the cost of magnesium source. Two different magnesium sources were used for phosphorus recovery: pure magnesium chloride and nanofiltration(NF) saline water retentate. The paper focuses on the impact of ionic strength on phosphorus recovery performance that has not been reported elsewhere. Experimental design with five numerical variables(Mg/P molar ratio, pH, PO_(4)^(3-)-P, NH_(4)^(+)-N, and Ca^(2+) levels) and one categorical variable(type of magnesium source) was used to evaluate the effect of ionic strength on phosphorus removal and struvite purity. The experimental data were analysed using analysis of variance(ANOVA) and principal component analysis(PCA). Results indicated that a magnesium source obtained from NF retentate was as effective as MgCl_(2) for struvite precipitation. It was also revealed that ionic strength had a more positive effect on struvite purity than on phosphorus removal. Within the range of parameters studied in this research, high ionic strength, high p H and wastewater with high phosphate, high ammonium and low calcium contents were found to be the most favourable conditions for struvite precipitation. Findings from this study will be beneficial to determine the feasibility of using high ionic strength saline water, such as NF seawater retentate, as a magnesium source for phosphorus recovery from wastewater that is rich in ammoniumnitrogen and phosphate.

关 键 词：Phosphorus recovery STRUVITE Ionic strength WASTEWATER Nanofiltration retentate 

分 类 号：X713[环境科学与工程—环境工程]