工业集聚区集中污水处理厂难降解有机物高标准深度处理研究

Study on high standard advanced treatment of refractory organic matter in centralized wastewater treatment plant of industrial agglomeration area

以某工业集聚区集中污水处理厂二级生化出水为对象,采用臭氧氧化技术进行难降解有机物高标准深度处理试验研究,考察臭氧氧化和臭氧-滤池耦合工艺处理效能。结果表明,原水COD为44.0~59.9mg/L,当臭氧投加量为150mg/L左右时,出水COD为19.2~27.9mg/L,稳定达到天津市地方标准《城镇污水处理厂污染物排放标准》(DB 12/599-2015)A标要求,但能耗、物耗较高,O3/ΔCOD平均达到4.90。将臭氧作为预氧化措施,投加量为50~55mg/L时,可大幅度提高废水可生化性,强化后续滤池生物降解作用,采用臭氧-炭滤工艺去除效果优于臭氧-砂滤工艺,出水COD为17.8~23.5mg/L,其中臭氧氧化和炭滤平均去除比例为35.5%和26.6%。原水有机物相对分子质量主要集中在100~200kDa,经高投加量臭氧氧化后出水有机物相对分子质量小于30kDa。经低浓度臭氧预氧化后,分子质量为30~100kDa的有机物比例提升21%,颗粒炭优先去除小相对分子质量有机物,炭滤柱出水有机物相对分子质量集中在100~200kDa。

The pretreatment of refractory organic matter from secondary biochemical effluent of a centralized wastewater treatment plant in an industrial agglomeration was studied by ozone oxidation technology,and the ozone oxidation and ozone-filter combination process efficiency was investigated.When the ozone dosage was about 150 mg/L,the COD decreased from 44.4~59.9 mg/L in the influent to 19.2~27.9 mg/L in the effluent,which was stable meet the level A criteria in the Discharge standard of pollutant for municipal wastewater treatment plant of Tianjin(DB12/599-2015),but the energy and material consumption were high,the average O3/ΔCOD was4.90.With Ozone as pre-oxidation measure,When the dosage was 50~55 mg/L,the biodegradability of wastewater can be greatly improved,and the biodegradation of subsequent filter can be enhanced.The ozone-carbon filtration process was better than the ozone-sand filtration process,and the effluent COD was 17.8~23.5 mg/L,and the average removal ratio of ozone oxidation and carbon filtration was 35.5%and 26.6%.The molecular weight of organics in raw water was mainly concentrated in 100~200 kDa,and the molecular weight of the effluent organic matter after oxidation by high dosage was less than 30 kDa.After pre-oxidation with low concentration of ozone,the proportion of organic matter with a molecular weight of 30~100 kDa was increased by 21%.Granular carbon preferred to remove small molecular weight organic matter,and the molecular weight of the effluent organic matter of the carbon filter column is concentrated at 100~200 kDa.