Characterization of an organic filter medium for the biofiltration treatment of air contaminated with 1,2‐dichlorobenzene

Abstract

Laboratory experiments were conducted to determine the potential for removing 1,2-dichlorobenzene (1,2-DCB) in gaseous phase by biofiltration. Experiments were carried out over 8 months in a steel tank (0.45 m 3 ) using an organic filter medium composed of peat, maple wood chips, chicken manure and 1,2-DCB-contaminated soil. During the first 6 months, the biofilter was operated without injecting 1,2-DCB in order to characterize the physicochemical, mechanical and microbiological properties of the filter bed. The results revealed that it is an excellent medium for both microbial development (up to 10 9 cells g −1 dry soil for heterotrophic bacteria) and long-term stability with a limited drop of pressure (30 cm of water) and no clogging. Over the final 2 months, the biofilter treated air laden with 1,2-DCB (0.30 and 0.75 g m −3 ) and the maximum elimination capacity reached was 9 g m −3 h −1 (inlet load of 13 g m −3 h −1 ), which represented 69% efficiency. Elimination performance was strongly dependent upon inlet concentration, sorption/desorption and biodegradation phenomena occurring in the filter medium. Sorption/desorption and biodegradation mechanisms during the start-up period were characterized using the elimination efficiency (%). At the beginning of the 1,2-DCB injection, the microorganisms were strongly impacted and sorption/desorption phenomena prevailed. With the decrease of the inlet concentration, biodegradation progressively increased to become the most important mechanism. It was concluded that biofiltration possesses an excellent potential for treating volatile chlorinated benzene, known to be recalcitrant to biodegradation.

Description of Citricoccus nitrophenolicus sp. nov., a para-nitrophenol degrading actinobacterium isolated from a wastewater treatment plant and emended description of the genus Citricoccus Altenburger et al. 2002

“…Microorganisms are capable of degrading a diverse range of xenobiotics and this property has been exploited in bioremediation in situ and in technical facilities like wastewater treatment plants and biofilters (Coutu et al 2003;Knudsen et al 2000). Environments polluted with para-nitrophenol (hereafter designated pNP) are common due to its widespread use in the manufacture of explosives, drugs, dyes, plasticizers, organophosphorus pesticides and as an agent for darkening of leather (Spain 1995;Trapido and Kallas 2000).…”

Study on Gaseous Chlorobenzene Treatment by a Bio-Trickling Filter: Degradation Mechanism and Microbial Community

“…The bio-trickling filter (BTF) was introduced for the removal of odorous gases and soluble volatile organic compounds from exhaust gas in the mid-1980s. Coutu et al found that the biological method achieved a removal efficiency of 69% with 1,2-dichlorobenzene [5]. Rahul et al found that the maximum BTEX (benzene, toluene, ethylbenzene, and xylene) removal rate reached 99.85% when corn-cob was used with an inlet BTEX concentration of 97 mg•m −3 and an EHRT (equilibrium hydraulic retention time) of 3.06 min [6].…”

Thermal Analysis of the Role of Condensation in PCR with Capillary Tubes

“…As condensation occurs naturally when saturated air is cooled to its dew point, its presence on instruments can affect performance outcomes in various applications. These include biofiltration [2], gaseous separation in chromatography [3], and vapor ionization in mass spectrometry [4]. Even minute volumes of condensate can hamper X-ray scattering [5] and atomic force microscope (AFM) measurements [6].…”