Department of Civil and Environmental Engineering, Dankook University, 152, Jukjeon-ro, Suji-gu, Yongin-si, Gyeonggi-do, Republic of Korea.
Water Analysis and Research Center, Water Research Corporation, Daejeon, Republic of Korea.
Chemosphere. 2021 Oct;281:130765. doi: 10.1016/j.chemosphere.2021.130765. Epub 2021 May 3.
Implementation of an ultraviolet (UV)-induced advanced oxidation process (AOP) before coagulation was found to enhance the removal of algae cells. However, the effect of UV-induced AOPs on extracellular cellular organic matter (EOM) and on its coagulation and removal was neglected. This study investigated the impact of UV-induced AOPs (UV/Cl, UV/ClO, and UV/HO) on EOM from Microcystis aeruginosa, and its coagulation and removal by a conventional gravity system (CGS), dissolved air flotation, and a low-energy flash-pressurized flotation (FPF) process. The changes in EOM characteristics before and after the UV-induced AOPs were based on UV absorbance (UV) and liquid chromatography with organic carbon detection analysis. The reduction in UV increased with an increasing dose of oxidant and UV irradiation. The reduction in UV for UV/Cl, UV/ClO and UV/HO was 59.5%, 26.5%, and 17.5% respectively, for 0.71 mM equimolar concentration of oxidant and 1920 mJ/cm UV irradiation, as evident from a pseudo-first order kinetics study. Similarly, degradation of the high molecular weight to low molecular weight (LMW) fraction was pronounced for UV/Cl. The coagulation efficiency decreased after UV-induced AOP in the following order: UV/HO > UV/ClO > UV/Cl. By contrast, the low-energy FPF process showed a higher removal of LMW fractions than CGS. Thus, low-energy FPF could be an alternative technology for the UV-induced AOP treatment system.
在混凝前实施紫外（UV）诱导的高级氧化工艺（AOP）被发现可以增强藻类细胞的去除。然而，UV 诱导 AOP 对细胞外细胞有机物质（EOM）及其混凝去除的影响却被忽视了。本研究考察了 UV 诱导的 AOPs（UV/Cl、UV/ClO 和 UV/HO）对铜绿微囊藻的 EOM 的影响，以及传统重力系统（CGS）、溶气浮选和低能耗闪压浮选（FPF）工艺对其的混凝去除效果。EOM 特性的变化是基于 UV 吸收（UV）和液相色谱-有机碳检测分析。随着氧化剂剂量和 UV 照射的增加，UV 的减少量增加。在 0.71mM 等摩尔浓度的氧化剂和 1920mJ/cm 的 UV 照射下，UV/Cl、UV/ClO 和 UV/HO 的 UV 减少量分别为 59.5%、26.5%和 17.5%，这可以从准一级动力学研究中得到证明。同样，UV/Cl 对高分子量向低分子量（LMW）部分的降解也很明显。在 UV 诱导 AOP 后，混凝效率按以下顺序降低：UV/HO>UV/ClO>UV/Cl。相比之下，低能耗 FPF 工艺对 LMW 部分的去除率高于 CGS。因此，低能耗 FPF 可能是 UV 诱导 AOP 处理系统的替代技术。
