Continuous biological waste gas treatment in stirred trickle-bed reactor with discontinuous removal of biomass

Abstract

A new reactor for biological waste gas treatment was developed to eliminate continuous solvents from waste gases. A trickle‐bed reactor was chosen with discontinuous movement of the packed bed and intermittent percolation. The reactor was operated with toluene as the solvent and an optimum average biomass concentration of between 5 and 30 kg dry cell weight per cubic meter packed bed (m3pb). This biomass concentration resulted in a high volumetric degradation rate. Reduction of surplus biomass by stirring and trickling caused a prolonged service life and prevented clogging of the trickle bed and a pressure drop increase. The pressure drop after biomass reduction was almost identical to the theoretical pressure drop as calculated for the irregular packed bed without biomass. The reduction in biomass and intermittent percolation of mineral medium resulted in high volumetric degradation rates of about 100 g of toluene m−3pb h−1 at a load of 150 g of toluene m−3pb h−1. Such a removal rate with a trickle‐bed reactor was not reported before. ©1998 John Wiley & Sons, Inc. Biotechnol Bioeng 57: 497‐503, 1998.

Bioreactors for treatment of VOCs and odours – A review

“…The control strategies suggested are of three types: mechanical, chemical or biological. Mechanical treatment includes bed stirring (Wubker et al, 1997;Laurenzis et al, 1998) or bed back washings with water (counter-current washings), which permit the draining of excess accumulated biomass (Smith et al, 1996). Chemical treatments include dissociation of the chemical binding between the biomass and the bed particle surface either by damage to the biomass by creating nutrient or water deficiency, or utilization of disinfecting agents (Diks et al, 1994;Schonduve et al, 1996;Cox and Deshusses, 1999;Armon et al, 2000;Chen and Stewart, 2000).…”

Biodegradation of gaseous styrene by Brevibacillus sp. using a novel agitating biotrickling filter

“…However, backwashing required high liquid flow rates to obtain full medium fluidization and larger reactor volume to allow for bed expansion during fluidization (Smith et al 1996). Little data have been reported for removing excess biomass by stirring the packed bed (Laurenzis et al 1998).…”

A bioactive foam reactor for the removal of volatile organic compounds: system performance and model development

“…These methods include: chemical rinses to physically remove the excess biomass accumulation, limitations of nutrient sources and bioreactor modifications using suitable packing materials [7][8][9][10]. These methods have expanded the range of bioreactor applications for higher VOC concentrations and gas flow rates; however, they often fail to consistently maintain high performance.…”