HAOFei-lin,SHENMing-wei.Effect of Secondary Settling Tank Operation Conditions on Retention Characteristics of Microplastics in Wastewater Treatment Plant[J].China Water & Wastewater,2024,40(3):38-45.
Effect of Secondary Settling Tank Operation Conditions on Retention Characteristics of Microplastics in Wastewater Treatment Plant
China Water & Wastewater[ISSN:1000-4062/CN:12-1073/TU]
volume:
第40卷
Number:
第3期
Page:
38-45
Column:
Date of publication:
2024-02-01
- Keywords:
- microplastic; wastewater treatment plant; secondary settling tank; retention; operation parameter; water distribution mode
- Abstract:
- This paper investigated the effect of three operation parameters (microplastic concentration in influent, sludge concentration and hydraulic loading rate) and two water distribution modes (peripheral-feed and peripheral-overflow, central?feed and peripheral-overflow) on the retention characteristics of three typical microplastic particles (polyethylene, polypropylene and polyvinyl chloride) in secondary settling tank at the end of the wastewater treatment process, so as to explore the low-cost and efficient retention of microplastics in existing operational wastewater treatment plants. The retention efficiency of microplastic particles in the secondary settling tank was effectively improved by adjusting its operation parameters and changing its water distribution mode. The retention rates of polyethylene and polypropylene microplastic particles were improved by nearly 20% by using the central-feed mode. The microplastic particles in effluent from the secondary settling tank were mainly those more harmful to humans with equivalent diameter less than 35 μm. In addition, the optimized regulation scheme which did not affect the main process of wastewater treatment plant was proposed by using variance analysis method.
Last Update:
2024-02-01