氯消毒工艺对饮用水中多环芳烃的去除规律  

PAHs Removal Rule by Chlorine Disinfection Process in Drinking Water

作　　者：刘祥[1] 

机构地区：[1]河海大学环境学院,江苏南京210098

出　　处：《净水技术》2017年第4期15-20,共6页Water Purification Technology

摘　　要：以南京某净水厂原水、滤后水、出厂水和自配水为对象,研究了不同pH值和氯投加量条件下,氯消毒对多环芳烃的去除规律及其产物。结果表明:净水厂氯消毒工艺对总PAHs的去除率为28.33%,2~4环芳烃的去除率分别为26.64%、27.39%、36.55%;氯投量为2mg/L时,浓度梯度3 000 ng/L萘、菲去除率均是浓度梯度200 ng/L的2倍以上,低pH有利于萘、菲的去除。随着氯投增加,200ng/L萘、菲去除率增加幅度较3 000 ng/L更为显著;酸性条件下,萘、菲与Cl_2发生亲电取代和氧化反应,消毒产物主要为1-氯萘、1,4-二氯萘、9-氯菲、9,10-二氯菲、1,4-萘醌、9,10-菲醌;碱性条件下,萘、菲可能以氧化、开环等方式被去除,产物可能为1-萘酚、9-菲酚、邻苯二甲酸、2,2-联苯二甲酸。Polycyclic aromatic hydrocarbons （PAHs） removal characteristics were tested with raw water, filtered water and finished water in a drinking water treatment plant located in Nanjing. The results showed that, total PAHs removal rate was 28.33% in water treatment works disinfection process, and 2 ？4 rings PAHs removal rate were 26.64%,27.39% and 36.55%, respectively. Effect of chlorine dosage and pH on the removal of polycyclic aromatic hydrocarbons and by-products were studied, it turned out that, when chlorine dosage was 2 mg/L, 3 000 ng/L Nap and Phe removal rate were 2 times more than 200 ng/L, it was good for removing Nap and Phe under the condition of low pH value; with the increase of chlorine dosage, 200 ng/L Nap and Phe removal rate were increased more obviously than 3 000 ng/L. Under the condition of acid, mechanism of Nap and Phe were electrophilic substitution and oxidation reaction, disinfection by-products are mainly 1 -chlorinenaphthalene, 1, 4-dichloronaphthalene,9-chlorinephenanthrene, 9, 10- dichlorophenanthrene, 1, 4-naphthoquinone,9, 10-phenanthrenequinone; Under alkaline conditions, disinfection by-products are mainly 1-naphthol, 9-phenanthrol, phthalic acid, 2,2-biphenyl 2 formic acid, Nap and Phe were likely to be removed by oxidation and ring-opening reaction.

关 键 词：多环芳烃 氯消毒 净水厂 消毒副产物 

分 类 号：X703[环境科学与工程—环境工程]