Related Experiment Video
Updated: Aug 9, 2026
08:13
A Novel Bioreactor for High Density Cultivation of Diverse Microbial Communities
Published on: December 25, 2015
Improving urban wastewaters using natural microbial communities in bench-scale reactors
Bertrans-Tubau Lluís1, Abril Meritxell1, Maestre Alba1
1BETA Technological Centre- University of Vic- Central University of Catalunya (BETA- UVIC- UCC), Carretera de Roda 70, 08500- Vic, Barcelona, Spain.
Bioresource Technology
|August 7, 2026
Summary
Small wastewater facilities can improve effluent quality using benthic and planktonic microbial systems. These systems effectively reduce E. coli, nutrients, and some emerging contaminants, offering a scalable tertiary treatment solution.
Area of Science:
- Environmental Microbiology
- Water Treatment Engineering
- Ecotoxicology
Background:
- Small urban wastewater facilities (<10,000 population equivalents) face challenges meeting stricter effluent quality standards.
- Current regulations may not mandate nutrient, faecal contamination, or contaminants of emerging concern (CECs) control for these facilities.
- There is a need for cost-effective tertiary treatment solutions for small-scale wastewater treatment plants.
Purpose of the Study:
- To evaluate the efficacy of benthic and planktonic microbial communities, individually and combined, for enhancing secondary-treated effluent quality.
- To assess the impact of microbial inoculum from wastewater-impacted ecosystems on treatment performance and operational costs.
- To investigate the removal of specific CECs and the factors influencing system performance.
Main Methods:
- Laboratory-controlled experiments using benthic and planktonic microbial systems, with and without inoculum from wastewater-impacted ecosystems.
- Assessment of microbial community performance in reducing Escherichia coli, nitrogen, and phosphorus.
- Quantification of removal rates for selected CECs (e.g., fluoxetine, citalopram).
- Correlation analysis between system performance and parameters like algal biomass and organic matter content.
Main Results:
- Benthic and combined benthic-planktonic systems achieved significant reductions in Escherichia coli (>2 log), nitrogen (83-97%), and phosphorus (70-75%).
- Fluoxetine and citalopram demonstrated higher removal rates compared to other evaluated CECs, though with considerable treatment variability.
- System performance was positively associated with algal biomass, total organic matter, and microalgal abundance.
Conclusions:
- Benthic and combined benthic-planktonic microbial systems show promise for tertiary wastewater treatment in small facilities.
- The use of inoculum from impacted ecosystems may offer cost-effective operational benefits.
- The experimental approach is a scalable pilot for improving effluent quality, addressing nutrient and CEC removal.
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