二级生化出水的深度处理研究  

Research on Advanced Treatment of Secondary Biochemical Effluent

作　　者：王锋 WANGFe ng(Solvay Investment Co.,Ltd.,Shanghai 201108,China)

机构地区：[1]索尔维投资有限公司,上海201108

出　　处：《中国资源综合利用》2021年第5期192-195,共4页China Resources Comprehensive Utilization

摘　　要：某污水处理厂二级生化出水的化学需氧量(COD)为250 mg/L,氨氮(NH_(3)-N)为35 mg/L,总磷(TP)为4 mg/L。本文针对该污水处理厂二级生化出水,采用次氯酸钠(NaClO)降解NH_(3)-N,利用聚合氯化铝(PAC)化学沉淀去除TP,并使用臭氧/双氧水高级氧化工艺降解水中的有机物。结果发现,当NaClO的投加量为1.196 g/L,NH_(3)-N由35 mg/L降至3.0 mg/L,去除率达到91.4%;当PAC投加量为0.2 g/L,TP从4.0 mg/L降至0.2 mg/L,去除率达到95%;NaClO氧化和PAC沉淀后,COD由250 mg/L降至175 mg/L。之后采用臭氧和臭氧/双氧水联用技术进一步对COD进行降解。对比发现,臭氧/双氧水比单独臭氧的氧化能力强。在臭氧投加量为258 mg/L,双氧水投加量为90 mg/L时,COD由175 mg/L降至35 mg/L,去除率为80%。经"次氯酸钠氧化+聚合氯化铝沉淀+臭氧/双氧水氧化"组合工艺处理后,最终出水COD为35 mg/L,NH_(3)-N为3.0 mg/L,TP为0.2 mg/L,达到《城镇污水处理厂污染物排放标准》(GB 18918—2002)的一级A标准。In the secondary biochemical effluent of a sewage treatment plant,the chemical oxygen demand(COD)is 250 mg/L,the ammonia nitrogen(NH_(3)-N)is 35 mg/L,and the total phosphorus(TP)is 4 mg/L.In this paper,for the secondary biochemical effluent of the sewage treatment plant,sodium hypochlorite(NaClO)is used to degrade NH_(3)-N,polyaluminum chloride(PAC)is used to chemically precipitate to remove TP,and an ozone/hydrogen peroxide advanced oxidation process is used to degrade organic matter in the water.It is found that when the dosage of NaClO is 1.196 g/L,NH_(3)-N is reduced from 35 mg/L to 3.0 mg/L,and the removal rate reaches 91.4%;when the dosage of PAC is 0.2 g/L,TP decreases from4.0 mg/L to 0.2 mg/L,and the removal rate reaches 95%;after NaClO oxidation and PAC precipitation,COD decreases from 250 mg/L to 175 mg/L.Afterwards,COD is further degraded by ozone and ozone/hydrogen peroxide combined technology.By comparison,it is found that ozone/hydrogen peroxide has a stronger oxidation ability than ozone alone.When the dosage of ozone is 258 mg/L and the dosage of hydrogen peroxide is 90 mg/L,COD is reduced from 175 mg/L to 35 mg/L,and the removal rate is 80%.After the combined process of"NaClO oxidation+PAC precipitation+ozone/hydrogen peroxide oxidation",the final effluent COD is 35 mg/L,NH_(3)-N is 3.0 mg/L,TP is 0.2 mg/L,which meets the Class A standard of the"Emission Standard of Pollutants for Urban Sewage Treatment Plants"(GB 18918—2002).

关 键 词：臭氧/双氧水 高级氧化 次氯酸钠 混凝沉降 

分 类 号：X791[环境科学与工程—环境工程]