混凝—铁碳微电解—次氯酸钠氧化处理高氮废水  

Treatment of high nitrogen wastewater by coagulation-iron carbon microelectrolysis-sodium hypochlorite oxidation process

作　　者：黄雷 刘叶芳 乐孝楠 黄瑞敏 HUANG Lei;LIU Yefang;LE Xiaonan;HUANG Ruimin(School of Environment and Energy,South China University of Technology,Guangzhou 510006,China;Key Laboratory of Pollution Control and Ecosystem Restoration in Industy Clusters,Ministry of Education,Guangzhou 510006,China)

机构地区：[1]华南理工大学环境与能源学院,广东广州510006 [2]工业聚集区污染控制与生态修复教育部重点实验室,广东广州510006

出　　处：《工业水处理》2022年第4期125-131,共7页Industrial Water Treatment

摘　　要：某印染工业园内的印花废水水量波动大,导致综合污水处理厂氮负荷高。采用混凝—铁碳微电解—次氯酸钠氧化组合工艺对该高氮废水进行处理。实验结果表明,在不调节初始pH、硫酸亚铁与聚丙烯酰胺投加量分别为400、15 mg/L的条件下,混凝阶段的COD去除率达到83.12%。在初始pH为4、铁碳质量比为1∶1、铁投加量为60 g/L、气水比为5∶1、HRT为120 min的条件下,对混凝出水进行铁碳微电解,出水pH升至6.91,COD和NO_(3)^(-)-N的去除率分别为50.26%、53.66%,NH_(4)^(+)-N为NO_(3)^(-)-N的主要还原产物。用次氯酸钠氧化法处理微电解出水,未调节初始pH、次氯酸钠与总凯氏氮质量比为8.5∶1、反应时间为30 min时,TN、NH_(4)^(+)-N的去除率分别为88.56%、97.75%。经该组合工艺间歇处理后,出水COD≤55 mg/L、TN≤14 mg/L、NH_(4)^(+)-N≤1 mg/L,可达到《纺织染整工业水污染物排放标准》(GB 4287—2012)表2的直接排放要求。经核算,该工艺的药剂成本为5.09元/t。In order to solve the problem of high nitrogen load caused by large fluctuation of wastewater in a printing and dyeing industrial park,a combined coagulation-iron carbon microelectrolysis-sodium hypochlorite oxidation process was used to treat the high nitrogen wastewater.The experimental results showed that the COD removal rate in coagulation stage reached 83.12%under the conditions of no adjustment of initial pH,ferrous sulfate and polyacrylamide dosage of 400 and 15 mg/L,respectively.Under the conditions of initial pH of 4,iron-carbon mass ratio of 1∶1,iron dosage of 60 g/L,gas-water ratio of 5∶1 and HRT of 120 min,iron-carbon microelectrolysis was applied to the coagulation effluent.The effluent pH increased to 6.91,and the removal rates of COD and NO_(3)^(-)-N were50.26%and 53.66%,respectively,with NH_(4)^(+)-N as the main reduction product of NO_(3)^(-)-N.The microelectrolysis effluent was treated with sodium hypochlorite.Under the conditions of no adjustment of initial pH,sodium hypochlorite to total Kjeldahl nitrogen mass ratio of 8.5∶1 and reaction time of 30 min,the removal rates of TN and NH_(4)^(+)-N were 88.56%and 97.75%,respectively.After intermittent treatment of combined process,the effluent COD≤55mg/L,TN≤14 mg/L and NH_(4)^(+)-N≤1 mg/L,met the direct discharge requirements in Table 2 of the Discharge standards of water pollutants for dyeing and finishing of textile industry(GB 4287—2012).After calculating,the cost of chemical agent of the process is 5.09 Yuan per ton.

关 键 词：印花废水 混凝 铁碳微电解 次氯酸钠 

分 类 号：X703[环境科学与工程—环境工程]