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Updated: Jun 8, 2026
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A Novel Bioreactor for High Density Cultivation of Diverse Microbial Communities
Published on: December 25, 2015
Pilot-scale experience with biological nutrient removal and biomass yield reduction in a liquid-solid circulating
Nabin Chowdhury1, George Nakhla, Jesse Zhu
1Department of Civil and Environmental Engineering, The University of Western Ontario, London, Ontario, Canada.
Summary
A pilot-scale liquid-solid circulating fluidized bed (LSCFB) bioreactor effectively removed organic matter, nitrogen, and phosphorus from wastewater. This biological nutrient removal system achieved high removal rates without chemicals, meeting criteria for nonpotable reuse.
Area of Science:
- Environmental Engineering
- Biotechnology
- Wastewater Treatment
Background:
- Biological nutrient removal is crucial for wastewater treatment and water reuse.
- Conventional methods often require chemical additions.
- Developing cost-effective and efficient biological systems is essential.
Purpose of the Study:
- To evaluate the commercial viability of a pilot-scale liquid-solid circulating fluidized bed (LSCFB) bioreactor.
- To assess the system's performance for biological nutrient removal (nitrogen and phosphorus).
- To determine the effluent quality for nonpotable wastewater reuse.
Main Methods:
- Development of a pilot-scale LSCFB bioreactor using lava rock as biomass carrier media.
- Operation at specific loading rates for Chemical Oxygen Demand (COD), Nitrogen (N), and Phosphorus (P).
- Measurement of nutrient removal efficiencies and effluent characteristics.
Main Results:
- Achieved high removal rates: ~90% organic, ~80% nitrogen, ~70% phosphorus.
- Produced effluent meeting nonpotable reuse criteria (<10 mg TN/L, <10 mg SBOD/L).
- Demonstrated significant reduction in biomass yield (~75%) due to long solids retention time (SRT).
Conclusions:
- The LSCFB bioreactor shows commercial viability for biological nutrient removal.
- The system effectively removes nutrients and organic matter without chemical inputs.
- The technology facilitates wastewater reuse by producing high-quality effluent with reduced biomass yield.
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