title: Influence of the gas composition on the efficiency of ammonia stripping of biogas digestate.
abstract: Impact of strip gas composition on side stream ammonia stripping, a technology aiming at the reduction of high ammonia levels in anaerobic reactors, was investigated. Evaluation of the effect of oxygen contact during air stripping showed a distinct, though lower than perceived, inhibition of anaerobic microflora. To circumvent, the feasibility and possible constraints of biogas and flue gas as alternatives in side stream stripping were studied. Experiments, with ammonia bicarbonate model solution and digestate, were conducted. It was demonstrated that the stripping performance is negatively correlated to the CO2 level in the strip gas with a progressive performance loss towards higher concentrations. In contrast to biogas with its high CO2 content, the efficiency reduction observed for flue gas was significantly less pronounced. The later provides the additional benefit that its high thermal energy can be re-utilized in the stripping unit and it is therefore considered a viable alternative for air.
authors.affiliation: Institute for Environmental Biotechnology, IFA-Tulln, University of Natural Resources and Life Sciences, Vienna, Konrad-Lorenz Straße 20, 3430 Tulln, Austria. Electronic address: johannes.bousek@boku.ac.at.
authors.forename: J
authors.initials: J
authors.lastname: Bousek
authors.affiliation: Institute for Environmental Biotechnology, IFA-Tulln, University of Natural Resources and Life Sciences, Vienna, Konrad-Lorenz Straße 20, 3430 Tulln, Austria.
authors.forename: D
authors.initials: D
authors.lastname: Scroccaro
authors.affiliation: Institute for Environmental Biotechnology, IFA-Tulln, University of Natural Resources and Life Sciences, Vienna, Konrad-Lorenz Straße 20, 3430 Tulln, Austria.
authors.forename: Jan
authors.initials: J
authors.lastname: Sima
authors.affiliation: Institute of Sanitary Engineering and Water Pollution Control, University of Natural Resources and Life Sciences, Vienna, Muthgasse 18, 1190 Wien, Austria.
authors.forename: Norbert
authors.initials: N
authors.lastname: Weissenbacher
authors.affiliation: Institute for Environmental Biotechnology, IFA-Tulln, University of Natural Resources and Life Sciences, Vienna, Konrad-Lorenz Straße 20, 3430 Tulln, Austria.
authors.forename: W
authors.initials: W
authors.lastname: Fuchs
mesh_terms: D000641:Ammonia / Q000737:chemistry*; D056804:Biofuels; D019149:Bioreactors; D002245:Carbon Dioxide / Q000737:chemistry; D003246:Conservation of Energy Resources / Q000379:methods; D010100:Oxygen / Q000737:chemistry; D014866:Waste Products
chemical_list: D056804:Biofuels; D014866:Waste Products; D002245:Carbon Dioxide; D000641:Ammonia; D010100:Oxygen
keywords: Ammonia removal; Anaerobic digestion; Biogas; Flue gas; Side stream stripping