Effect of humic substances on phosphorus removal by struvite precipitation》.pdf

Chemosphere 141 (2015) 94–99 Contents lists available at ScienceDirect Chemosphere journal homepage: www. /loc ate/chemosphere Effect of humic substances on phosphorus removal by struvite precipitation Zhen Zhou ⇑, Dalong Hu, Weichao Ren, Yuzeng Zhao, Lu-Man Jiang, Luochun Wang College of Environmental and Chemical Engineering, Shanghai University of Electric Power, Shanghai 200090, China College of Environmental and Chemical Engineering, Shanghai University of Electric Power, Changyang Rd #2588, Shanghai 200090, China h i g h l i g h t s Inhibitory effect of humic substances on struvite precipitation was studied. Humic substances inhibited struvite precipitation at pH 8.0–9.0 and low Mg/P ratio. Humic substances changed structure and morphology of precipitated struvite crystals. Coprecipitation of humic substances compromised precipitated struvite purity. a r t i c l e i n f o a b s t r a c t Article history: Humic substances (HS) are a major fraction of dissolved organic matters in wastewater. The effect of HS Received 1 August 2014 on phosphorus removal by struvite precipitation was investigated using synthetic wastewater under dif- Received in revised form 26 May 2015 ferent initial pH values, Mg/P molar ratios and HS concentrations. The composition, morphology and Accepted 29 June 2015 thermal properties of harvested precipitates were analyzed by X-ray diffraction (XRD), scanning electron microscope (SEM) and thermo-gravimetric analysis (