A membrane bioreactor for an innovative biological nitrogen removal process

Area of Science:

• Environmental Engineering
• Biotechnology
• Wastewater Treatment

Background:

• Biological nitrogen removal is crucial for wastewater treatment.
• Nitrification-denitrification processes are widely used but can be optimized.
• Membrane bioreactors (MBRs) offer advantages in solid-liquid separation.

Purpose of the Study:

• To develop and evaluate a hybrid system for simultaneous organic and nitrogen removal.
• To assess the performance of a membrane bioreactor (MBR) integrated into a nitrification-denitrification process.
• To determine the efficiency of the hybrid system under various loading rates.

Main Methods:

• A laboratory-scale hybrid system combining aerobic and anoxic tanks with an MBR was constructed.
• The system treated glucose-based synthetic wastewater.
• Performance was evaluated based on chemical oxygen demand (COD) and total nitrogen removal, sludge concentration, and effluent quality.

Main Results:

• The hybrid system achieved over 95% COD removal and over 90% total nitrogen removal.
• High sludge suspended solids (SS) concentrations (≥6 g/L) were maintained.
• Effluent SS was less than 1 mg/L, indicating excellent solid-liquid separation.
• High loading rates for COD (up to 2,100 mg/L-d) and total nitrogen (up to 170 mg N/L-d) were handled effectively.

Conclusions:

• The developed hybrid system is highly effective for simultaneous organic and nitrogen removal.
• The integration of MBR technology enhances wastewater treatment efficiency and effluent quality.
• The system demonstrates robustness in handling high organic and nitrogen loads within a short hydraulic retention time (HRT).