title: Performance evaluation and optimization of field-scale bioscrubbers for intensive pig house exhaust air treatment in northern Germany.
abstract: The treatment of exhaust air from three intensive pig houses in northern Germany by field-scale bioscrubbers (BS.1, BS.2, and BS.3) were evaluated monthly in 2015. The simultaneous removal of NH3and CH4was investigated by connecting a second bioscrubber (BS.2-2) to one of the three bioscrubbers (BS.2) to create a two-series connected bioscrubber (BS.2+BS.2-2). Additionally, whether isolated methanotrophic bacterial inoculation in BS.2-2 intensified CH4removal was examined. Average NH3removal efficiencies of 86%, 80%, and 77% were observed for BS.1, BS.2, and BS.3, respectively, under fluctuate NH3inlet concentrations (variation of 22%-54%) throughout the study year. However, average CH4removal efficiencies were lower than 10% in the three bioscrubbers. The pH of the recirculation water, which ranged from 5.7 to 8.1, was demonstrated to be an important factor for NH3removal and negatively correlated with NH3removal and NH4+-N concentration in the recirculation water. The dominant NH3-oxidizing and methanotrophic bacteria in the bioscrubbers, analysed by transmission electron microscopy, were Nitrosomonas sp. and Type I methanotrophs, respectively. NH3removal efficiency reached 100% in the two-series connected bioscrubber, however, CH4removal was still low (average of 2%). After inoculating isolated methanotrophic bacteria into BS.2-2, the average CH4removal was enhanced to 35%, offering a great option for bioscrubbers application to intensify CH4removal. Therefore, a two-series connected bioscrubber inoculated with methanotrophic bacteria would be an option for simultaneous removal of NH3and CH4from the exhaust air of animal houses.
authors.affiliation: Center for Earth System Research and Sustainability, Institute of Soil Science, Universität Hamburg, Allende-Platz 2, 20146 Hamburg, Germany. Electronic address: fang.liu@uni-hamburg.de.
authors.forename: Fang
authors.initials: F
authors.lastname: Liu
authors.affiliation: Center for Earth System Research and Sustainability, Institute of Soil Science, Universität Hamburg, Allende-Platz 2, 20146 Hamburg, Germany.
authors.forename: Claudia
authors.initials: C
authors.lastname: Fiencke
authors.affiliation: College of Engineering, China Agricultural University, Qinghua East Road 17, 100083 Beijing, China. Electronic address: jianbinguo@cau.edu.cn.
authors.forename: Jianbin
authors.initials: J
authors.lastname: Guo
authors.affiliation: RIMU Agrartechnologie GmbH, Harrenstetter Straße 29, 49757 Werlte, Germany.
authors.forename: Robert
authors.initials: R
authors.lastname: Rieth
authors.affiliation: College of Engineering, China Agricultural University, Qinghua East Road 17, 100083 Beijing, China.
authors.forename: Renjie
authors.initials: R
authors.lastname: Dong
authors.affiliation: Center for Earth System Research and Sustainability, Institute of Soil Science, Universität Hamburg, Allende-Platz 2, 20146 Hamburg, Germany.
authors.forename: Eva-Maria
authors.initials: EM
authors.lastname: Pfeiffer
mesh_terms: D000393:Air Pollutants / Q000032:analysis; D000397:Air Pollution / Q000032:analysis / Q000706:statistics & numerical data*; D000641:Ammonia / Q000032:analysis; D000822:Animal Husbandry; D001673:Biodegradation, Environmental; D005858:Germany; D008697:Methane / Q000032:analysis
chemical_list: D000393:Air Pollutants; D000641:Ammonia; D008697:Methane
keywords: Ammonia removal; Bioscrubber; Methane oxidation; Optimization; Pig house