TY - JOUR
T1 - Removal efficiency and molecular transformation of dissolved organic matter in combined sewer overflow during micro-nano bubble ozonation treatment
AU - Wang, Cong
AU - Xia, Qing
AU - Wang, Yang
AU - Zhou, Chuanting
AU - Zhao, Xiaodan
AU - Wu, Min
AU - Zhou, Zhen
N1 - Publisher Copyright:
© 2025 Elsevier B.V.
PY - 2025/12/31
Y1 - 2025/12/31
N2 - This study investigated the efficiency of conventional ozonation and micro-nano bubble (MNB) ozonation in dissolved organic matter (DOM) removal from combined sewer overflow (CSO), and utilized Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) to characterize DOM transformation. The results indicated that DOM removal efficiency increased with both ozone concentration and flow rate. The degradation rate constant for MNB ozonation was 2.8 times that of conventional ozonation at the temperature of 35°C. Under the optimal pH of 9, MNB ozonation achieved 58.1 % removal rate after 60 min. FT-ICR MS analysis revealed complex DOM composition in CSO, identifying 3037 molecular formulas predominantly clustered into three categories: lipids, aliphatic/proteins, and lignin/carboxylic-rich alicyclic molecules (CRAM)-like structures. The elemental compositions consisted mainly of CHO, CHON, CHOS, and CHONS compounds. The increase in molecular formulas in effluents suggests complex transformations during ozonation. The addition of MNBs effectively enhanced the removal of lipids and lignins/CRAM-like compounds by ozonation. Changes in Ox species revealed oxidation addition. Additionally, N1-2O3-6 compounds were more readily eliminated during the MNB ozonation process. This study provided an in-depth understanding of DOM transformation in a practical CSO treatment and guidance for designing an efficient CSO treatment process.
AB - This study investigated the efficiency of conventional ozonation and micro-nano bubble (MNB) ozonation in dissolved organic matter (DOM) removal from combined sewer overflow (CSO), and utilized Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) to characterize DOM transformation. The results indicated that DOM removal efficiency increased with both ozone concentration and flow rate. The degradation rate constant for MNB ozonation was 2.8 times that of conventional ozonation at the temperature of 35°C. Under the optimal pH of 9, MNB ozonation achieved 58.1 % removal rate after 60 min. FT-ICR MS analysis revealed complex DOM composition in CSO, identifying 3037 molecular formulas predominantly clustered into three categories: lipids, aliphatic/proteins, and lignin/carboxylic-rich alicyclic molecules (CRAM)-like structures. The elemental compositions consisted mainly of CHO, CHON, CHOS, and CHONS compounds. The increase in molecular formulas in effluents suggests complex transformations during ozonation. The addition of MNBs effectively enhanced the removal of lipids and lignins/CRAM-like compounds by ozonation. Changes in Ox species revealed oxidation addition. Additionally, N1-2O3-6 compounds were more readily eliminated during the MNB ozonation process. This study provided an in-depth understanding of DOM transformation in a practical CSO treatment and guidance for designing an efficient CSO treatment process.
KW - Combined sewer overflow
KW - Dissolved organic matter
KW - FT-ICR MS
KW - Micro-nano bubble
KW - Ozonation
UR - https://www.scopus.com/pages/publications/105014731199
U2 - 10.1016/j.seppur.2025.134940
DO - 10.1016/j.seppur.2025.134940
M3 - 文章
AN - SCOPUS:105014731199
SN - 1383-5866
VL - 379
JO - Separation and Purification Technology
JF - Separation and Purification Technology
M1 - 134940
ER -