HUANGChen-duo,YANGQing,JIANGXian-cong,et al.Spatiotemporal Migration and Removal of PAHs in Reclaimed Wastewater Treatment Plant[J].China Water & Wastewater,2025,41(19):116-125.
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Spatiotemporal Migration and Removal of PAHs in Reclaimed Wastewater Treatment Plant

China Water & Wastewater[ISSN:1000-4062/CN:12-1073/TU] volume: 第41卷 Number: 第19期 Page: 116-125 Column: Date of publication: 2025-10-01
Author(s):
HUANG　Chen-duo1;  YANG　Qing2;  JIANG　Xian-cong3;  ZHANG　Shi-yong2;  WANG　Ya-xin2;  Lü　Ji-kai1;  WANG　Biao1;  LIU　Xiu-hong1
（1. Beijing Key Laboratory of Water Quality Science and Water Environment Restoration Engineering， Beijing University of Technology， Beijing 100124， China； 2. National Engineering Laboratory for Urban Wastewater Advanced Treatment and Resource Reuse， Beijing University of Technology， Beijing 100124， China； 3. Key Laboratory of Satellite Remote Sensing， Ministry of Ecology and Environment， Beijing 100094， China）
Keywords:
reclaimed wastewater treatment plant;  polycyclic aromatic hydrocarbons (PAHs);  distribution characteristics;  removal rate;  influencing factor
Abstract:
Polycyclic aromatic hydrocarbons (PAHs), as emerging contaminants with carcinogenicity and mutagenicity, pose potential risks to water environmental safety during their migration and transformation process in reclaimed wastewater treatment plants. This study conducted research on three typical reclaimed wastewater treatment plants in Beijing from August 2023 to June 2024, revealing the spatiotemporal distribution characteristics and removal patterns of PAHs. In the primary treatment, the aeration grit chamber achieved the removal of 7.3%-32.6% of PAHs through physical interception. The removal rate of oxidation ditch process in the secondary treatment reached 18.7%-33.9%. In the tertiary treatment stage, the biofilter (with a removal rate of 26.6%-31.7%) and the high-density sedimentation tank (with a removal rate of 27.6%-51.8%) further enhanced the removal of PAHs through bio-chemical synergy. Activated sludge adsorption was the dominant pathway for the removal of PAHs. The PAHs concentration showed significant seasonal fluctuations. The peak concentration in autumn and winter could be up to 4.12-7.52 times higher than that in spring and summer. The proportion of benzo [k] fluoranthene in plants A and C was the highest, while the proportion of anthracene in plant B was the highest, reflecting the differences in pollution sources among different water sources. Correlation analysis indicated that dissolved chemical oxygen demand (SCOD) and sludge concentration (MLSS) were the core influencing factors of PAHs concentration, and ammonia nitrogen and total nitrogen also had significant effects on PAHs concentration. The research suggests improving the removal efficiency of PAHs by optimizing the dynamic regulation of SCOD and MLSS.
Last Update: 2025-10-01