CAS Key Laboratory for Urban Pollutant Conversion, Department of Chemistry, University of Science and Technology of China, Hefei 230026, China.
Sci Rep. 2016 May 18;6:26115. doi: 10.1038/srep26115.
To meet the high quality standard of receiving water, the coagulation process using polyferric chloride (PFC) was used to further improve the water quality of effluent from wastewater treatment plants. Uniform design (UD) coupled with response surface methodology (RSM) was adopted to assess the effects of the main influence factors: coagulant dosage, pH and basicity, on the removal of total organic carbon (TOC), NH4(+)-N and PO4(3-)-P. A desirability function approach was used to effectively optimize the coagulation process for the comprehensive removal of TOC, NH4(+)-N and PO4(3-)-P to upgrade the effluent quality in practical application. The optimized operating conditions were: dosage 28 mg/L, pH 8.5 and basicity 0.001. The corresponding removal efficiencies for TOC, NH4(+)-N and PO4(3-)-P were 77.2%, 94.6% and 20.8%, respectively. More importantly, the effluent quality could upgrade to surface water Class V of China through coagulation under optimal region. In addition, grey relational analysis (GRA) prioritized these three factors as: pH > basicity > dosage (for TOC), basicity > dosage > pH (for NH4(+)-N), pH > dosage > basicity (for PO4(3-)-P), which would help identify the most important factor to control the treatment efficiency of various effluent quality indexes by PFC coagulation.
为了满足接收水的高质量标准，采用聚合氯化铁（PFC）的混凝工艺进一步改善了污水处理厂出水的水质。采用均匀设计（UD）和响应面法（RSM）评估了主要影响因素：混凝剂剂量、pH 值和碱度对总有机碳（TOC）、NH4(+)-N 和 PO4(3-)-P 去除的影响。采用可接受性函数方法有效优化了 PFC 混凝工艺，以综合去除 TOC、NH4(+)-N 和 PO4(3-)-P，从而在实际应用中提高出水质量。优化的操作条件为：剂量 28mg/L，pH 值 8.5，碱度 0.001。TOC、NH4(+)-N 和 PO4(3-)-P 的相应去除率分别为 77.2%、94.6%和 20.8%。更重要的是，通过在最佳区域进行混凝，出水质量可提升至中国地表水 V 类标准。此外，灰色关联分析（GRA）优先考虑了这三个因素：pH 值>碱度>剂量（对于 TOC），碱度>剂量>pH 值（对于 NH4(+)-N），pH 值>剂量>碱度（对于 PO4(3-)-P），这有助于确定控制 PFC 混凝处理各种出水质量指标效率的最重要因素。
