School of Environment and Architecture, University of Shanghai for Science and Technology, 516 Jungong Road, 200093 Shanghai, China.
School of Environment and Architecture, University of Shanghai for Science and Technology, 516 Jungong Road, 200093 Shanghai, China.
Sci Total Environ. 2021 May 20;770:144767. doi: 10.1016/j.scitotenv.2020.144767. Epub 2021 Jan 23.
Ozone is a strong oxidant commonly used in drinking water treatment, but its role in the transformation/formation of organic matters (OMs) and disinfection by-products (DBPs) in the drinking water treatment chain had not been systematically studied. In this work the occurrence and building up of OMs, DBPs of trihalomethanes (THMs) and nitrosamines (NAs) during water purification steps under different pre-ozonation dosages have been studied through lab-scale and pilot-scale studies. Results indicated that 0-0.4 mg/L of pre-ozonation dosage could reduce organic load of following-up process steps but insufficient to control DBPs. Seasonal performances of a pilot plant indicated that the accumulation of DBPs was much less in summer than in winter. Furthermore the formation potential of NAs was higher in winter than summer when 0.4 mg/L pre-ozonation was dosed while the maximum removal efficiency of organic matter was found at a pre-ozonation dosage of 0.8 mg/L in summer. Finally a seasonal trade-off control strategy for both OMs and DBPs was proposed with an elucidated role of pre-ozonation in the drinking water treatment chain. This study provided working principles on optimizing pre-ozonation dosage and a seasonal control strategy for trade-off control of both OMs and DBPs in drinking water treatment plants.
臭氧是一种常用的饮用水处理氧化剂，但它在饮用水处理链中有机物（OMs）和消毒副产物（DBPs）的转化/形成中的作用尚未得到系统研究。在这项工作中，通过实验室规模和中试规模研究，研究了在不同预臭氧化剂量下的水净化步骤中 OMs、三卤甲烷（THMs）和亚硝胺（NAs）DBPs 的发生和积累。结果表明，0-0.4mg/L 的预臭氧化剂量可以降低后续处理步骤的有机负荷，但不足以控制 DBPs。中试装置的季节性性能表明，与冬季相比，夏季 DBPs 的积累要少得多。此外，当投加 0.4mg/L 预臭氧化时，冬季 NAs 的形成潜力高于夏季，而夏季有机物的最大去除效率则在 0.8mg/L 预臭氧化投加时达到。最后，提出了一种针对 OMs 和 DBPs 的季节性权衡控制策略，并阐明了预臭氧化在饮用水处理链中的作用。本研究为优化预臭氧化剂量以及饮用水处理厂中 OMs 和 DBPs 的季节性权衡控制策略提供了工作原理。
