Steady-state and transient-state performance of a biotrickling filter treating chlorobenzene-containing waste gas

• Published in: Applied microbiology and biotechnology 2004-07, Vol.65 (1), p.33-37
• Main Authors: Seignez, C, Adler, N, Thoeni, C, Stettler, M, Peringer, P, Holliger, C
• Format: Article
• Language: English
• Subjects: Air Pollutants - chemistry; Air Pollutants - metabolism; Bacteria - metabolism; biofilters; Biofiltration; Biological and medical sciences; Biological treatment of gaseous effluents; Biotechnology; Chlorobenzene; Chlorobenzenes - chemistry; Chlorobenzenes - metabolism; DCB (herbicide); Dichlorobenzene; Dissolved organic carbon; Efficiency; Environment and pollution; Filtration - instrumentation; Filtration - methods; Fundamental and applied biological sciences. Psychology; Gases - metabolism; Industrial applications and implications. Economical aspects; Load distribution; Mineralization; organochlorine compounds; pollutants; Trickling filters; waste gases; Waste treatment
• ISSN: 0175-7598; 1432-0614
• DOI: 10.1007/s00253-003-1531-0

Biotrickling filter (BTF) technology was applied for the treatment of waste gas containing a mixture of chlorobenzene and 1,2-dichlorobenzene. An adapted microbial community was immobilised on a structured packing material. The strategy followed was to reach high removal efficiencies at initially low mass loading rates followed by an increase of the latter. This procedure was successful and resulted in a short start-up period of only 2 weeks. A 3-month operation under steady-state conditions showed good performance, with >95% removal efficiency at a mass loading rate of 1,800 g m-3 day-1. Dimensionless concentration profiles showed that the chlorobenzenes were simultaneously degraded. Low dissolved organic carbon of 15 mg l-1 and stoichiometric chloride concentrations in the trickling liquid indicated complete mineralisation of the pollutant. Transient-state experiments with five times higher mass loading rates caused a decrease in the removal efficiency that recovered rapidly once the mass loading rate returned to its original steady-state level. A progressive increase of the mass loading rate in a long-term performance experiment showed that the removal efficiency could be kept stable between 95 and 99% at loads of up to 5,200 g m-3 day-1 over several days. Above this mass loading rate, the elimination capacity did not increase any further. These results demonstrated that with a well-adapted inoculum and optimal operation parameters, a BTF system with excellent performance and stability that efficiently removes a mixture of cholorobenzene vapours from air can be obtained.