Blackwater treatment using vertical greening: Efficiency and microbial community structure.

Area of Science:

• Environmental Engineering
• Wastewater Treatment Technologies
• Microbial Ecology

Background:

• Blackwater presents a significant challenge for wastewater treatment due to high nutrient loads.
• Conventional treatment methods can be energy-intensive and costly.
• Vertical greening systems offer a potential nature-based solution for decentralized wastewater management.

Purpose of the Study:

• To evaluate the efficacy of vertical greening systems for blackwater treatment.
• To determine the impact of hydraulic retention time (HRT) and drip frequency on treatment performance.
• To characterize the microbial community dynamics within the vertical greening system.

Main Methods:

• Systematic assessment of vertical greening system performance under varying HRT and drip frequencies.
• Analysis of nutrient removal efficiencies (NH4+-N, TP).
• High-throughput sequencing to characterize microbial community structure and shifts.

Main Results:

• Nutrient removal efficiencies for ammonium-nitrogen (NH4+-N) and total phosphate (TP) increased with extended HRT.
• Drip frequency significantly influenced TP removal.
• Microbial community diversity remained stable, but dominant bacterial groups shifted, with a proliferation of autotrophic nitrifying bacteria in the vertical direction.

Conclusions:

• Vertical greening systems are effective for treating blackwater, particularly for reducing NH4+-N levels.
• Optimizing HRT and drip frequency can enhance nutrient removal.
• The shift in microbial communities, favoring autotrophic nitrifiers, contributes to improved nitrogen removal in vertical configurations.