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Updated: Jun 9, 2026
08:24
Mesocosm-Scale Constructed Wetland Design for Wastewater Treatment
Published on: May 2, 2025
A new operation mode solving clogging problems of horizontal subsurface constructed wetlands
Changming Shen1, Dianhai Yang, Bingzhi Dong
1College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China. 0810050023@tongji.edu.cn
Summary
A novel reciprocating flow operation for horizontal subsurface constructed wetlands (SSFCW) significantly enhances wastewater treatment. This method improves pollutant removal and prevents clogging by promoting beneficial microbial activity.
Area of Science:
- Environmental Engineering
- Wastewater Treatment Technologies
- Wetland Systems
Background:
- Horizontal subsurface constructed wetlands (SSFCW) are effective for wastewater treatment but prone to clogging.
- Clogging limits the operational lifespan and efficiency of traditional SSFCW systems.
- Improving SSFCW performance is crucial for sustainable wastewater management.
Purpose of the Study:
- To evaluate a new periodic flow reversal operation mode for SSFCW.
- To assess the impact of this new mode on pollutant removal efficiency.
- To investigate the mechanisms behind improved performance and reduced clogging.
Main Methods:
- Implemented a reciprocating flow operation in SSFCW over three years.
- Compared pollutant removal efficiency against traditional continuous flow SSFCW.
- Analyzed microbial community changes and monitored water levels to assess clogging.
Main Results:
- The reciprocating SSFCW demonstrated superior pollutant removal compared to the traditional mode.
- Significantly higher microbial populations were observed in the reciprocating system, inhibiting organic accumulation.
- The reciprocating SSFCW maintained stable water levels, avoiding infiltration issues common in traditional systems.
Conclusions:
- Periodic flow reversal is a viable strategy to enhance SSFCW performance.
- Reciprocating flow mitigates clogging by promoting microbial activity and preventing localized pollutant buildup.
- This operational mode offers a sustainable solution for long-term, efficient wastewater treatment using constructed wetlands.
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