Related Experiment Videos
[Relationships between loading rates and nitrogen removal effectiveness in subsurface constructed wetlands].
Rong-she Zhang1, Guang-he Li, Qi Zhou
1Department of Environmental Science and Engineering, Tsinghua University, Beijing 100084, China.
Huan Jing Ke Xue= Huanjing Kexue
|May 12, 2006
Summary
Subsurface flow constructed wetlands (SFS) effectively remove nitrogen. Optimal performance occurs at specific inflow loads, with plant-based systems outperforming non-planted ones for enhanced nitrogen removal.
Area of Science:
- Environmental Engineering
- Water Quality Management
- Ecological Engineering
Context:
- Subsurface flow constructed wetlands (SFS) are crucial for wastewater treatment.
- Understanding nitrogen loading dynamics is vital for optimizing SFS performance.
- This study investigates nitrogen removal across various SFS configurations and loading rates.
Purpose:
- To evaluate nitrogen removal efficiency in SFS with different plant types (reeds, Zizania caduciflora) and a non-planted control.
- To determine the relationship between nitrogen inflow and outflow loading rates.
- To identify optimal operating conditions for SFS nitrogen removal.
Summary:
- Nitrogen loading removal rates were studied in field SFS over 15 months.
- Outflow nitrogen loading increased linearly with inflow loading, up to 8,000 mg/(m²d).
- Optimal SFS operation is between 2,000-4,000 mg/(m²d) inflow loading, with average removal rates of 1062-2007 mg/(m²d).
- Plant-based SFS, particularly reed beds (63% higher removal), significantly outperformed non-planted systems.
- Plant harvesting had minimal impact; plants primarily enhance the microenvironment and hydrology for better nitrogen removal.
Impact:
- Provides critical data for designing and managing SFS for efficient nitrogen removal.
- Highlights the importance of plant selection and inflow load management in SFS design.
- Offers insights into the mechanisms driving enhanced nitrogen removal in vegetated SFS.