Key Laboratory of Building Safety and Energy Efficiency, Ministry of Education, Department of Water Engineering and Science, College of Civil Engineering, Hunan University, Changsha 410082, China.
Key Laboratory of Building Safety and Energy Efficiency, Ministry of Education, Department of Water Engineering and Science, College of Civil Engineering, Hunan University, Changsha 410082, China.
J Environ Sci (China). 2022 Jul;117:21-27. doi: 10.1016/j.jes.2021.12.021. Epub 2022 Jan 4.
Pre-oxidation has been reported to be an effective way to remove algal cells in water, but the released algal organic matter (AOM) could be oxidized and lead to the increment in disinfection by-product (DBP) formation. The relationship between pre-oxidation and AOM-derived DBP formation needs to be approached more precisely. This study compared the impact of four pre-oxidants, ozone (O), chlorine dioxide (ClO), potassium permanganate (KMnO) and sodium hypochlorite (NaClO), on the formation of nitrogenous (N-) and carbonaceous (C-) DBPs in AOM chlorination. The characterization (fluorescent properties, molecular weight distribution and amino acids concentration) on AOM samples showed that the characterization properties variations after pre-oxidation were highly dependent on the oxidizing ability of oxidants. The disinfection experiments showed that O increased DBP formation most significantly, which was consistent with the result of characterization properties variations. Then canonical correspondent analysis (CCA) and Pearson's correlation analysis were conducted based on the characterization data and DBP formation. CCA indicated that C-DBPs formation was highly dependent on fluorescent data. The formation of haloacetic acids (HAAs) had a positive correlation with aromatic protein-like component while trichloromethane (TCM) had a positive correlation with fulvic acid-like component. Pearson's correlation analysis showed that low molecular weight fractions were favorable to form N-DBPs. Therefore, characterization data could provide the advantages in the control of DBP formation, which further revealed that KMnO and ClO were better options for removing algal cells as well as limiting DBP formation.
预氧化已被报道为去除水中藻类细胞的有效方法，但释放的藻类有机物（AOM）可能会被氧化，导致消毒副产物（DBP）形成增加。需要更精确地研究预氧化与 AOM 衍生 DBP 形成之间的关系。本研究比较了四种预氧化剂（臭氧（O）、二氧化氯（ClO）、高锰酸钾（KMnO）和次氯酸钠（NaClO））对 AOM 氯化过程中氮（N）和碳（C）DBP 形成的影响。对 AOM 样品的特性（荧光特性、分子量分布和氨基酸浓度）进行了研究，结果表明，预氧化后特性变化高度依赖于氧化剂的氧化能力。消毒实验表明，O 对 DBP 形成的促进作用最为显著，这与特性变化的结果一致。然后基于特性数据和 DBP 形成进行典型对应分析（CCA）和 Pearson 相关性分析。CCA 表明 C-DBPs 的形成高度依赖于荧光数据。卤乙酸（HAAs）的形成与芳香蛋白样组分呈正相关，而三氯甲烷（TCM）与富里酸样组分呈正相关。Pearson 相关性分析表明，低分子量部分有利于形成 N-DBPs。因此，特性数据可以在控制 DBP 形成方面提供优势，进一步表明 KMnO 和 ClO 是去除藻类细胞和限制 DBP 形成的更好选择。
