Related Experiment Video
Updated: May 19, 2026

Development of Sulfidogenic Sludge from Marine Sediments and Trichloroethylene Reduction in an Upflow Anaerobic Sludge Blanket Reactor
Published on: October 15, 2015
Reverse-flow strategy in biofilters treating CS₂ emissions
Naiara Rojo1, Gorka Gallastegui, Luis Gurtubay
1Department of Chemical and Environmental Engineering, Engineering Faculty, University of the Basque Country, Alda Urkijo s/n, 48013 Bilbao, Spain. naiara.rojo@ehu.es
This study found that reverse-flow biofilters effectively degrade carbon disulfide (CS₂), even under challenging conditions. While reduced empty bed residence time (EBRT) decreased efficiency, reverse flow promoted better biomass distribution for improved CS₂ biodegradation.
Area of Science:
- Environmental biotechnology
- Bioreactor engineering
- Chemical engineering
Background:
- Carbon disulfide (CS₂) possesses bacteriostatic properties, inhibiting its biodegradation in traditional biofilters.
- Effective treatment of CS₂ emissions is crucial due to its environmental and health impacts.
Purpose of the Study:
- To compare the biodegradation performance of biofilters operating in downflow and reverse-flow modes when treating CS₂.
- To assess the impact of operational changes on CS₂ removal efficiency in different biofilter configurations.
Main Methods:
- Laboratory-scale biofilters were operated in downflow and reverse-flow modes.
- Treated air containing CS₂ under varying conditions: process shutdown, increased inlet concentration, and interrupted humidification.
- Evaluated biodegradation performance at different empty bed residence times (EBRTs) of 240 s and 60 s.
Main Results:
- Biofilters showed resilience to short-term operational changes at an EBRT of 240 s, irrespective of flow mode.
- A significant decrease in CS₂ removal efficiency was observed in all biofilters when EBRT was reduced to 60 s.
- Reverse-flow mode resulted in a more homogeneous biomass distribution throughout the biofilter bed.
Conclusions:
- Reverse-flow biofiltration is a promising strategy for enhanced CS₂ biodegradation.
- Biomass homogeneity in reverse-flow systems offers benefits even after returning to unidirectional flow.
- Optimizing EBRT is critical for maintaining high CS₂ removal efficiency in biofilters.
More Related Videos
Related Concept Videos
Bioremediation
Bioreactor Controls-II
Bioreactor Design and Operational System
Microbial Leaching

