Constructed wetland using corncob charcoal substrate: pollutants removal and intensification

Area of Science:

• Environmental Engineering
• Wastewater Treatment Technologies
• Sustainable Materials

Background:

• Constructed wetlands (VFCWs) are effective for wastewater treatment.
• Exploring alternative substrates like corncob charcoal is crucial for sustainable practices.
• Understanding substrate performance impacts treatment efficiency.

Purpose of the Study:

• To evaluate the feasibility of corncob charcoal as a substrate in laboratory-scale VFCWs.
• To compare its pollutant removal efficiency against traditional clay ceramisite.
• To investigate its performance under varying conditions, including low C/N ratios.

Main Methods:

• Four laboratory-scale vertical flow constructed wetlands (VFCWs) were established.
• Pollutant concentrations (COD, NH4+-N, TP) were monitored.
• Performance was assessed under aerobic conditions and varying C/N ratios.

Main Results:

• Corncob charcoal VFCWs showed high removal efficiencies for COD (91.5%) and NH4+-N (91.3%) under aeration.
• Corncob charcoal outperformed clay ceramisite in TP removal (40.0% vs 32.0%) and under low C/N ratios for TN removal (36.89% vs 4.1%).
• Raw corncob substrate exhibited higher COD emissions than corncob charcoal.

Conclusions:

• Corncob charcoal is a viable substrate for VFCWs, particularly under aeration.
• Its self-supplying carbon source property enhances denitrification, especially at low C/N ratios.
• Corncob charcoal offers a sustainable alternative for constructed wetland applications.