Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
579958 | Journal of Hazardous Materials | 2010 | 7 Pages |
Abstract
The formation of struvite (MgNH4PO4·6H2O) in wastewater treatment plants can lead to scaling and thus operational problems reducing the treatment efficiency. However, struvite has significant commercial value as an agricultural fertilizer. Therefore, controlled struvite formation in wastewater treatment plants not only presents an opportunity to recover nutrients but also corresponds to the valorization of wastes. NH4-N and PO4-P removal and recovery from the effluent of a full-scale sewage sludge anaerobic digester via controlled struvite precipitation were investigated in this study. The effect of the residual heavy metal and micropollutant content of the formed struvite on fertilizer quality was also evaluated. Removal efficiencies of NH4-N, PO4-P and COD were 89.35%, 95% and 39.78% when Mg:N:P molar ratio was 1.5:1:1 and pH was 9.0. Mercury, nickel, zinc and chrome concentrations derived from struvite precipitation were below the regulatory limit for fertilizer usage in Turkey. The precipitate did not contain polychlorinated biphenyls (PCB). X-ray diffraction (XRD) analysis conducted on the precipitate indicated a struvite formation.
Related Topics
Physical Sciences and Engineering
Chemical Engineering
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Authors
Ayla Uysal, Y. Dilsad Yilmazel, Goksel N. Demirer,