title: Comparative assessment of a biofilter, a biotrickling filter and a hollow fiber membrane bioreactor for odor treatment in wastewater treatment plants.
abstract: A low abatement efficiency for the hydrophobic fraction of odorous emissions and a high footprint are often pointed out as the major drawbacks of conventional biotechnologies for odor treatment. In this work, two conventional biotechnologies (a compost-based biofilter, BF, and a biotrickling filter, BTF), and a hollow-fiber membrane bioreactor (HF-MBR) were comparatively evaluated in terms of odor abatement potential and pressure drop (ΔP) at empty bed residence times (EBRTs) ranging from 4 to 84 s, during the treatment of methyl-mercaptan, toluene, alpha-pinene and hexane at trace level concentrations (0.75-4.9 mg m(-3)). High removal efficiencies (RE > 90% regardless of the air pollutant) were recorded in the BF at EBRTs ≥ 8 s, although the high ΔP across the packed bed limited its cost-effective operation to EBRTs > 19 s. A complete methyl-mercaptan, toluene and alpha-pinene removal was recorded in the BTF at EBRTs ≥ 4 s and ΔP lower than 33 mmH2O (∼611 Pa mbed(-1)), whereas slightly lower REs were observed for hexane (∼88%). The HF-MBR completely removed methyl-mercaptan and toluene at all EBRTs tested, but exhibited an unstable alpha-pinene removal performance as a result of biomass accumulation and a low hexane abatement efficiency. Thus, a periodical membrane-cleaning procedure was required to ensure a steady abatement performance. Finally, a high bacterial diversity was observed in the three bioreactors in spite of the low carbon source spectrum present in the air emission.
authors.affiliation: Department of Chemical Engineering and Environmental Technology, Escuela de Ingenierías Industriales, Sede Dr. Mergelina, University of Valladolid, Dr Mergelina s/n, 47011 Valladolid, Spain(1).
authors.forename: Raquel
authors.initials: R
authors.lastname: Lebrero
authors.affiliation: Department of Chemical Engineering and Environmental Technology, Escuela de Ingenierías Industriales, Sede Dr. Mergelina, University of Valladolid, Dr Mergelina s/n, 47011 Valladolid, Spain(1).
authors.forename: Ana Celina
authors.initials: AC
authors.lastname: Gondim
authors.affiliation: Department of Chemical Engineering and Environmental Technology, Escuela de Ingenierías Industriales, Sede Dr. Mergelina, University of Valladolid, Dr Mergelina s/n, 47011 Valladolid, Spain(1).
authors.forename: Rebeca
authors.initials: R
authors.lastname: Pérez
authors.affiliation: Department of Chemical Engineering and Environmental Technology, Escuela de Ingenierías Industriales, Sede Dr. Mergelina, University of Valladolid, Dr Mergelina s/n, 47011 Valladolid, Spain(1).
authors.forename: Pedro A
authors.initials: PA
authors.lastname: García-Encina
authors.affiliation: Department of Chemical Engineering and Environmental Technology, Escuela de Ingenierías Industriales, Sede Dr. Mergelina, University of Valladolid, Dr Mergelina s/n, 47011 Valladolid, Spain(1). Electronic address: mutora@iq.uva.es.
authors.forename: Raúl
authors.initials: R
authors.lastname: Muñoz
mesh_terms: D001419:Bacteria / Q000254:growth & development; D001673:Biodegradation, Environmental; D019149:Bioreactors / Q000382:microbiology*; D058645:Denaturing Gradient Gel Electrophoresis; D005374:Filtration / Q000295:instrumentation*; D008567:Membranes, Artificial; D008969:Molecular Sequence Data; D009812:Odorants / Q000032:analysis*; D011312:Pressure; D013997:Time Factors; D055549:Volatile Organic Compounds / Q000032:analysis; D062065:Wastewater / Q000382:microbiology*; D018508:Water Purification / Q000295:instrumentation*
chemical_list: D008567:Membranes, Artificial; D055549:Volatile Organic Compounds; D062065:Wastewater
keywords: Biofilter; Biotrickling filter; Membrane bioreactor; Odor treatment; Volatile organic compounds