期刊名称：Journal of Environmental & Analytical Toxicology
电子版ISSN：2161-0525
出版年度：2019
卷号：9
期号：2
页码：1-8
语种：English
出版社：OMICS International
摘要：Magnesium ammonium phosphate hexahydrate (MgNH4PO4.6H2O), commonly known as struvite is a crystalline mineral of low solubility. In wastewater treatment facilities, separating phosphorus by conversion to struvite could reduce its content in the wastewater. The experiment conducted for local wastewater sources to identify better source and recover struvite for phosphatic fertilizer evaluation. Chemical precipitation through pH elevation and (Mg2+:NH4+-N:PO43--P) molar ratio were used to recover NH4+ and PO43- as struvite from sewerage water of different sites. To recover (MAP) magnesium ammonium phosphate hexahydrate from the four different sources, chemicals including MgCl2.6H2O+Na3PO4 were applied at molar ratio (Mg2+:NH4+-N:PO43-P=1.2:1:1) and at different pH ranging from 8.0 to 11.0. Results indicated that maximum P removal was obtained as 87% at pH 10.5 from the source of I-9 sector containing high levels of P. For N results indicated that maximum N removal was obtained as 67% at pH 10.0 from the same source of P removal. In the experiment among various combinations, comprising of Mg:N:P ratio, pH levels and stirring speeds, the stirring speed of 250 rpm for 30 minutes was more desireable for struvite precipitation process. The MAP precipitation significantly reduced the contents of NH4+ and PO43- in sewerage water at different sites. So, it is necessary to develop the optimum conditions for small-scale and commercial production of struvite, because struvite recovery is technically feasible and economically beneficial. Therefore, this technology provides opportunities to recover phosphorus sustainably from sewerage water and preserve phosphorus reserves.
关键词：Precipitation; Struvite separation; Stirring speed; Chemical ratio; Sewerage
