河流型水源地源水典型氯化消毒副产物及其前体物的强化去除工艺

Enhanced processes for removal of typical chlorinated disinfection by-products and their precursors from river-type water source

以长三角某典型河流型水源地源水为研究对象,设计了传统工艺及基于凹凸棒土处理单元的6种强化工艺,对各工艺及其处理单元应用于典型氯化消毒副产物(三卤甲烷和卤乙酸)及其前体物控制的技术和经济可行性进行了系统分析。结果表明,预O3+凹土强化混凝+O3-GAC强化的工艺对上述2种消毒副产物及其前体物的控制效果最佳;在传统工艺中单纯增加O3处理也能在一定程度上提高其对消毒副产物前体物的去除效果;KMnO4控制消毒副产物的效果一般,但KMnO4处理可强化后续单元对消毒副产物前体物的去除效果。各工艺处理出水中三卤甲烷和卤乙酸单项指标均能达标,但传统工艺和经凹土强化混凝+GAC强化的工艺出水三卤甲烷4种化合物的实测浓度与其各自限值的比值之和均大于1.0,不能满足水质要求,必须进行强化处理。凹土强化混凝单元在6种强化工艺条件下对三卤甲烷生成潜能(THMFP)和卤乙酸生成潜能(HAAFP)的去除率较传统混凝单元平均提高15.99%和4.92%;各强化工艺对THMFP和HAAFP的去除率较传统工艺均提高20%以上(除凹土强化混凝+GAC强化的工艺外),消毒副产物产生量降低40%以上,工艺成本降低20%以上。

The traditional water supply process and six kinds of attapulgite-based enhanced processes were designed,and technical and economic feasibilities of each process and its processing units on the control of typical chlorinated disinfection by-products(DBPs)(i.e.trihalomethanes,THMs,and haloacetic acids,HAAs) and their precursors were systematically analyzed in a typical river-type water source in the Yangtze River Delta.Results showed that the best control effect of the above two kinds of DBPs and their precursors occurred in the enhanced process of preozonation & attapulgite enhanced coagulation & O3-GAC.Removal of those DBP precursors could also be improved by simply increasing ozonation unit in the traditional process to some extent.Potassium permanganate treatment had a general effect on the control of the two kinds of DBPs,while it did enhance removal effects of the DBP precursors in the follow-up processing units.The single indexes of DBPs mentioned above in the effluents treated by all of the processes met the standard,while the sums of ratios of measured concentrations of all four types of THMs and their respective thresholds were both greater than 1.0 by traditional process and the enhanced process of attapulgite-based coagulation & GAC,which could not meet the requirement of water quality and must be strengthenly treated.The average increases in removal rates of THMs formation potential(THMFP) and HAAs formation potential(HAAFP) by attapulgite-enhanced coagulation process unit were 15.99% and 4.92%,respectively,in six kinds of enhanced processes,compared to the traditional coagulation process unit.The average increases in removal rates of THMFP and HAAFP by all of the enhanced processes were both greater than 20%(except for the enhanced process of attapulgite-based coagulation & GAC),meanwhile,the reducing rates of DBPs generation and the process costs were greater than 40% and 20%,respectively,compared to the traditional process.