溴离子对污水处理工艺消毒副产物生成势的影响

Effect of Bromide Ion on Formation Potential of Disinfection By-products in Wastewater Treatment Process

利用消毒副产物(DBPs)三卤甲烷生成势(THMs FP)和卤乙酸生成势(HAAs FP),研究了含溴污水在某校园污水处理工艺中沿程DBPs前体物变化及溴离子对DBPs类型的影响规律。结果表明,以A^(2)/O生物工艺为主的二级处理,对污水中DOC、UV_(254)的去除效果十分显著,THMs FP在沿程处理中呈逐渐降低的趋势,HAAs FP与SUVA值经二级处理后呈升高趋势,即芳香性与不饱和度高的溶解性小分子有机物是HAAs的重要前体物,含溴消毒副产物(Br-DBPs)占总DBPs的50%~65%;经A^(2)/O工艺处理后,当Br^(-)浓度由100μg/L增加到300μg/L时,THMs中溴结合因子(BIF)由0.5增加到0.8,HAAs中BIF由0.51增加到0.62,溴代为主的THMs FP和HAAs FP呈逐渐增加的趋势,即溴离子浓度的增加使DBPs的种类由氯代向溴代转化。

The changes in disinfection by-products (DBPs) precursors and the effect of bromide ion on DBPs types in bromide-containing wastewater from a campus wastewater treatment process were investigated by using the formation potentials of two DBPs:trihalomethane formation potential (THMs FP)and haloacetic acid formation potential (HAAs FP).The secondary treatment based on A^(2)/O process had a good removal performance of DOC and UV;in wastewater.Profile of the concentration of THMs FP was a decreasing trend along the treatment process,whereas the profile of the concentrations of HAAs FP and SUVA was an increasing trend after secondary treatment.Therefore,soluble small molecular organics with high aromaticity and desaturation were important precursors of HAAs,and bromide-containing disinfection by-products (Br-DBPs) accounted for 50%-65% of the total DBPs.After A^(2)/O treatment,with the increasing of bromide ion concentration from 100μg/L to 300μg/L,bromide-binding factor (BIF) of THMs increased from 0.5 to 0.8,and the BIF of HAAs increased from 0.51 to 0.62.The concentration of dominated bromide,THMs FP and HAAs FP,showed a trend of gradual increase,that was,the increase of bromide ion concentration transformed DBPs from chlorides to bromides.