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Updated: Jul 7, 2026
08:24
Mesocosm-Scale Constructed Wetland Design for Wastewater Treatment
Published on: May 2, 2025
[Removal nitrogen in wavy subsurface-flow constructed wetland utilizing aeration and recirculation]
Yong-zheng Ren1, Bei-ping Zhang, Ben-zeng Hai
1School of Environmental Science & Engineering, Huazhong University of Science and Technology, Wuhan 430074, China. renyz@163.com
Huan Jing Ke Xue= Huanjing Kexue
|February 23, 2008
Summary
Modified constructed wetlands with aeration tubes significantly boost ammonium nitrogen removal. Enhanced dissolved oxygen and nitrifying bacteria led to over 90% nitrification and improved hydraulic load tolerance.
Area of Science:
- Environmental Engineering
- Water Treatment Technologies
- Microbial Ecology
Context:
- Constructed wetlands are crucial for wastewater treatment.
- Traditional wavy subsurface-flow constructed wetlands (W-SFCW) face challenges in ammonium nitrogen removal efficiency.
- Optimizing dissolved oxygen (DO) and microbial activity is key to enhancing nitrification.
Purpose:
- To improve ammonium nitrogen removal rates in constructed wetlands.
- To investigate the impact of installing aeration tubes in specific intervals of W-SFCWs.
- To assess the effect of effluent recirculation on total nitrogen (TN) removal.
Summary:
- Aeration tubes installed in the second wave interval of W-SFCWs enhanced DO levels and nitrification rates.
- Nitrifying bacteria dominated the third wave interval after most chemical oxygen demand (COD) removal, achieving over 90% nitrification.
- A 50% effluent recirculation rate significantly increased average TN removal efficiencies.
Impact:
- The modified W-SFCW demonstrated enhanced nitrification rates and improved tolerance to hydraulic loading.
- Achieved high removal efficiencies for ammonium nitrogen and total nitrogen.
- Provides a viable strategy for upgrading existing constructed wetland systems for more effective wastewater treatment.
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