铁碳微电解-混凝对印染废水二级生化出水的深度处理

Advanced treatment of the secondary biochemical effluent of dyeing wastewater via Fe-C microelectrolysis-coagulation

针对印染废水二级生化出水水质难降解且难以达标的现状,研究在不调节p H的前提下,采用铁碳微电解混凝工艺进行处理研究。通过单因素实验确定最优条件范围,建立响应面(response surface methods,RSM)分析实验,确定铁碳微电解的最佳工艺条件为:Fe的投量为72.1 g/L、m(C)∶m(Fe)为2.98∶1、水力停留时间(HRT)为2.6 h。最佳混凝条件为:Al2(SO4)3投量为100 mg/L、混凝沉淀时间为30 min。实验结果表明,在上述最优工艺条件下对该废水进行深度处理,对COD的去除率能达到50%以上,出水COD低至46.1 mg/L,达到提标后的《纺织染整工业水污染物排放标准》新标准(COD≤60 mg/L),其药剂处理成本为每吨印染废水0.355元左右,该法技术可行、经济合理。

As dyeing wastewater secondary biochemical effluent is refractory and cannot satisfy current discharge standards,iron-carbon（ Fe-C） micro-electrolysis combined with coagulation was adopted for advanced treatment of dyeing wastewater without a p H adjustment. According to the experiment with a single factor,the range of best reaction conditions was found,then response surface methodology（ RSM） revealed that the optimum conditions of Fe-C micro-electrolysis reactions were as follows： the iron dosage of 72. 1 g / L,m（ C） ∶ m（ Fe） of 2. 98 ∶ 1,and the reaction time of 2. 6 h. In the coagulation process,the aluminum sulfate（ Al2（ SO4）3） dosage was 100 mg /L,and the coagulation sedimentation time was 30 min. Under the above operation conditions,the removal efficiency of chemical oxygen demand（ COD） reached more than 50%,with COD of effluent at 46. 1 mg / L,which achieved the new Wastewater Pollutants Discharge Standard for Textile Printing Industry（ COD≤6 0 mg / L）. The cost of the reagent is 0. 355 yuan per ton of dyeing wastewater. This process is feasible and reasonably priced.