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Updated: Jun 1, 2026
08:24
Mesocosm-Scale Constructed Wetland Design for Wastewater Treatment
Published on: May 2, 2025
Treating surface water with low nutrients concentration by mixed substrates constructed wetlands
Chun J Li1, Ming H Wan, Yang Dong
1School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, PR China. cjli@sjtu.edu.cn
Summary
This study enhanced nutrient removal in constructed wetlands using novel substrates like calcium silicate hydrate and vermiculite. Mixed substrates achieved over 91% total nitrogen removal, but phosphorus removal needs further improvement.
Area of Science:
- Environmental Engineering
- Water Treatment Technologies
- Eutrophication Control
Background:
- Constructed wetlands (CWs) are used for nutrient reduction but show limited efficiency with traditional substrates.
- Low nitrogen and phosphorus removal capacity of soil and gravel hinders CW performance in real-world applications.
Purpose of the Study:
- To enhance nutrient removal in constructed wetland systems.
- To evaluate novel substrates like calcium silicate hydrate (CSH), vermiculite, and ceramsite for nitrogen and phosphorus removal.
Main Methods:
- Investigated CSH, vermiculite, and ceramsite individually in static experiments.
- Conducted batch and continuous flow experiments with mixed substrates in CW systems.
- Evaluated performance under specific hydraulic retention time (HRT) and hydraulic loading rate (HLR).
Main Results:
- Calcium silicate hydrate (CSH) demonstrated high phosphorus removal efficiency (97%) in initial tests, though reduced in CW application.
- Vermiculite showed the highest ammonia nitrogen removal efficiency (65.91%), potentially influenced by microbial activity.
- Continuous-flow CW with mixed substrates achieved over 91% total nitrogen removal efficiency at an HRT of 18h and HLR of 0.496 m³/m³/d.
Conclusions:
- Mixed substrates in CWs significantly improve total nitrogen removal.
- While CSH shows promise for phosphorus removal, its efficiency in CWs requires further investigation.
- Further research is needed to enhance phosphorus removal efficiency in CW systems.
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