Beijing Key Laboratory for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China.
Engineering Research Center for Water Pollution Source Control & Eco-Remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China.
Environ Sci Pollut Res Int. 2023 Oct;30(50):109738-109750. doi: 10.1007/s11356-023-30028-3. Epub 2023 Sep 30.
Various advanced treatment processes including ultrafiltration (UF), ozonation, enhanced coagulation, and biological aerated filter (BAF) have been applied to reduce dissolved organic matter (DOM) from the secondary effluent of municipal wastewater treatment plants (MWTPs). In this study, DOM were characterized and the relationship between DOM characteristics and disinfection by-products (DBPs) generation was investigated systematically. Results showed that BAF and ozonation processes could significantly affect DOM characteristics in the treated effluents and the following DBP generation. UF and enhanced coagulation reduced the production of DBPs by removing large molecular hydrophobic organics. The removal of low molecule DOM by BAF resulted in a 67.6% reduction in trihalomethanes (THMs) production. Ozonation could oxidize large hydrophobic DOM into small hydrophilic molecules containing aldehyde and ketone groups, leading to 54% increase of halogenated aldehydes (HALs) and halogenated ketones (HKs). Humic acid (HA) was the main organic type in DOM and important precursor for THMs and dichloroacetonitrile (DCAN) formation. The generation of trichloromethane (TCM) showed a significant positive correlation (R = 0.987) with the specific ultraviolet absorbance at 254 nm (SUVA). Large molecule hydrophobic DOM devoted the most to the formation of carbonaceous disinfection by-products and [Formula: see text]-N content was an important factor affecting the generation of nitrogenous disinfection by-products. These results are important for the optimization of advanced treatment process in MWTPs, and controlling DBPs should consider the removal of low MW hydrophobic DOM and the reduction of SUVA.
各种先进的处理工艺，包括超滤（UF）、臭氧氧化、强化混凝和曝气生物滤池（BAF），已被应用于降低城市污水处理厂（MWTP）二级出水的溶解性有机物（DOM）。本研究系统地表征了 DOM，并研究了 DOM 特性与消毒副产物（DBPs）生成之间的关系。结果表明，BAF 和臭氧氧化工艺可显著影响处理出水的 DOM 特性及后续 DBP 的生成。UF 和强化混凝通过去除大分子量疏水性有机物来减少 DBPs 的生成。BAF 去除低分子量 DOM 导致三卤甲烷（THMs）生成减少 67.6%。臭氧氧化可将大疏水性 DOM 氧化成含有醛酮基团的小亲水性分子，导致卤代醛（HALs）和卤代酮（HKs）增加 54%。腐殖酸（HA）是 DOM 中的主要有机类型，也是 THMs 和二氯乙腈（DCAN）形成的重要前体。三氯甲烷（TCM）的生成与 254nm 处的特定紫外吸光度（SUVA）呈显著正相关（R=0.987）。大分子量疏水性 DOM 主要贡献于碳质 DBP 的形成，[Formula: see text]-N 含量是影响含氮 DBP 生成的重要因素。这些结果对优化 MWTP 中的高级处理工艺具有重要意义，控制 DBPs 应考虑去除低 MW 疏水性 DOM 和降低 SUVA。
