韩月,任逸,翟姝,张炜铭,吕路.污水生化出水有机物对氯贝酸臭氧降解的影响研究[J].环境科学学报,2019,39(11):3779-3785
污水生化出水有机物对氯贝酸臭氧降解的影响研究
- Effect of effluent organic matter on ozonation for clofibric acid degradation
- 基金项目：国家重点研发计划（No.2017YFE0107200）
- 韩月
- 污染控制与资源化研究国家重点实验室, 南京大学环境学院, 南京 210023
- 任逸
- 污染控制与资源化研究国家重点实验室, 南京大学环境学院, 南京 210023
- 翟姝
- 污染控制与资源化研究国家重点实验室, 南京大学环境学院, 南京 210023
- 张炜铭
- 1. 污染控制与资源化研究国家重点实验室, 南京大学环境学院, 南京 210023;2. 国家环境保护有机化工废水处理与资源化工程技术中心, 南京 210046;3. 南京大学常高新国际环保产业技术研究院, 常州 213125
- 吕路
- 1. 污染控制与资源化研究国家重点实验室, 南京大学环境学院, 南京 210023;2. 南京大学常高新国际环保产业技术研究院, 常州 213125
- 摘要：常规水处理技术无法有效去除痕量的药品和个人护理品（PPCPs），臭氧工艺因具有效果可观、二次污染小等优势，尤其适合用于生化尾水的深度处理.而污水生化出水有机物（EfOM）对臭氧降解PPCPs起着至关重要的作用.本文选取腐殖酸（HA）、牛血清蛋白（BSA）、海藻酸钠（AGS）和葡聚糖（Dextran）作为模拟EfOM 4种代表物质，以氯贝酸（CA）为PPCPs模板化合物，考察了模拟EfOM化合物浓度、反应时间及溶液初始pH对臭氧降解效果的影响规律和机制.结果表明，CA臭氧降解速率符合假一级动力学方程，模拟EfOM化合物为10 mg·L-1 TOC时，对CA臭氧降解效果呈现出HA > Dextran ≈ DW（超纯水） ≈ AGS > BSA的规律.HA可提高HO·的生成速率从而加快CA降解效率，反应速率常数提升了3倍，去除率提高了17.5%；而BSA则明显抑制HO·的生成，从而降低CA降解速率.HA的存在对CA臭氧降解影响较为复杂，研究发现当HA浓度为1 mg·L-1 TOC时，能促进HO·的生成和CA的降解，而当浓度升高时会表现出抑制作用.CA臭氧降解速率和反应过程中HO·生成均随着溶液初始pH的增加而增大.pH的变化还会影响HA对臭氧降解CA的作用效果.溶液初始pH为4时，HA投加可促进HO·生成和臭氧降解；但随着pH的升高，HA的存在形态会发生改变，从而表现出对CA臭氧降解效果的抑制作用.
- Abstract：Traditional wastewater treatment processes are not effective for trace pharmaceuticals and personal care products (PPCPs) removal. Due to the advantages of good performance, low secondary pollution, etc., ozonation is a promising technology for the treatment of secondary effluent. Effluent organic matter (EfOM) plays a vital role in ozonation for PPCPs degradation. Humic acid (HA), bovine serum albumin (BSA), sodium alginate (AGS) and dextran were selected as model EfOM to investigate the influence of EfOM concentration, reaction time and initial solution pH on the kinetics and mechanisms of ozonation, using clofibric acid (CA) as model refractory PPCP. The results indicate that the CA removal followed a pseudo-first-order kinetics, and the ozonation efficiency for CA removal in the presence of 10 mg·L-1 model EfOM (as TOC) addition followed the order of:HA > Dextran ≈ DW (deionized water) ≈ AGS > BSA. HA facilitated HO·formation and thus accelerated the degradation of CA. The reaction rate constant is three times higher and the removal rate increased by 17.5% compared with those without HA addition. BSA significantly inhibited the formation of HO·and decreased the rate of CA degradation. The concentration of HA showed a complicated effect on the degradation of CA. It facilitas the formation of HO·and the degradation of CA at the concentration of 1 mg·L-1 TOC, while it shows an inhibition effect at higher concentration. The degradation efficiency of CA and the formation of HO·always increased with the increase of initial pH in the presence of different model EfOM. The effect of HA on CA degradation differed at different pH. At pH 4, the addition of HA facilitated HO·formation and CA degradation, but at higher pH, HA showed an inhibition effect due to structural change.
