Bench-scale evaluation of a biofiltration system used to mitigate trichloroethylene contaminated air streams

• Published in: Advances in environmental research : an international journal of research in environmental science, engineering and technology Vol. 7; no. 1; pp. 97 - 104
• Main Authors: Lackey, Laura W., Gamble, Johnny R., Boles, Jeffrey L.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.11.2002
• Subjects: Bacteria; Biofiltration; chlorinated compounds; Cometabolism; Propane-oxidizing microorganisms; Pulse-feeding scheme; Trichloroethylene; Trichloroethylene; Pulse-feeding scheme; Biofiltration; Propane-oxidizing microorganisms; Cometabolism
• ISSN: 1093-0191; 1093-7927
• DOI: 10.1016/S1093-0191(01)00111-3

Improper disposal practices of the once widely used short-chained chlorinated aliphatics have made them a major component of groundwater contamination. Historically, pump and treat technology has been implemented to remediate and contain such aquifer water. After being pumped to the surface, the water is frequently treated with stripper technology. As a result, there is a high volume, low concentration contaminated air stream to either be directly emitted or treated prior to release in an effort to meet regulatory compliance. This work studied the feasibility of using biofiltration technology to remediate trichloroethylene (TCE) contaminated air streams. Furthermore, work focused on operational schemes that influenced the TCE degradation potential within the system. The bench-scale biofilter system contained 42 l of organic packing material and was inoculated with a propane-oxidizing microbial consortium. Propane, the primary substrate, and TCE were introduced into the biofilter in two distinct modes. Initially, TCE and propane were both continuously added to the biofilter system. The maximum TCE degradation observed under this continuous feeding scheme was 25%. Secondly, the TCE and propane were alternately pulsed or cycled in a step-wise fashion into the biofilter system. Under this operating environment, greater than 98% removal of TCE from the air stream was achieved.