Analysis and comparison of biotreatment of air polluted with ethanol using biofiltration and biotrickling filtration

Abstract

This study analyses the performance of ethanol biofiltration with percolation (biotrickling filtration, BTF) comparing to a conventional biofilter (biofiltration, BF). Two biofilters packed with clay balls were operated in a range of inlet concentrations of ethanol in the air varying from 0.47 to 2.36 g m⁻³. For both the BF and BTF, the specific growth rate (μ) and the elimination capacity (EC) decreased with the ethanol inlet concentration, presenting a kinetic of substrate inhibition. A Haldane-type model was adjusted for both biofilters in order to model both EC and μ as a function of the ethanol inlet concentration in the gas. The maximum EC was similar for both biofilters, at around 46 g m⁻³ h⁻¹, whereas the maximum μ was 0.0057 h⁻¹ for the BF and 0.0103 h⁻¹ for the BTF. The maximum of ethanol removed, occurned at the lowest inlet concentration of (0.47 g m⁻³), and reached 86% for the BF and 74% for the BTF.

Keywords:

• ethanol
• biodegradation
• biofiltration
• biotrickling filtration
• Haldane-type model
• substrate inhibition

Acknowledgements

Michèle Heitz acknowledges the Natural Sciences and Engineering Research Council of Canada for the financial support to this project. Karine Morotti would like to thank the Région Midi-Pyrénées of France for the financial support.