Authors: Shaoqi Zhou Yanyu Wu
Publish Date: 2011/07/13
Volume: 19, Issue: 2, Pages: 347-360
Abstract
The NH4N in synthetically prepared wastewater was removed using struvite precipitation technology A quadratic statistical modeling response surface methodology RSM was applied to investigate the improvement availability for highlevel removal of ammoniumnitrogen by struvite precipitation Then a chemical equilibrium model Visual MINTEQ was used to calculate the equilibrium speciation and saturation index in aqueous solution and solid phases In addition the availability of Mg2+ NH 4 + and PO 4 3− ions as a function of pH was modeled The predicted and experimental data indicated that the two models might describe the experiments well The results showed that pH was an important parameter in ammoniumnitrogen removals at low initial NH4N concentration P/N molar ratio was a limiting factor on struvite precipitation at high initial NH4N concentrationWithin the ranges of the investigated factors Visual MINTEQ program can be proposed to predetermine the concentration of ammonium precipitated by struvite and RSM can be used to predict total NH4N removal by both struvite precipitation and ammonia volatilization from our investigated system operated at high pH and opened to the atmosphereThe authors wish to gratefully acknowledge the financial supports from the Key Science and Technology Research Project of Peoples Republic of China Grant no 2008BAE64B05 2006BAJ04A124 the State Key Laboratory of Subtropical Building Science 2009ZB05 2010ZB04 2011ZB08 the Department of Science and Technology of Guangdong Province 2007A032500005 for this study and the Department of Guangzhou Science and Technology Bureau Grant no 2008A1D0011 Additionally the authors would like to express their sincere appreciation to the anonymous reviewers for their helpful comments and suggestions
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