title: Relationship between respiratory quotient, nitrification, and nitrous oxide emissions in a forced aerated composting process.
abstract: We assessed the relationship between respiratory quotient (RQ) and nitrification and nitrous oxide (N2O) emission in forced aerated composting using lab-scale reactors. Relatively high RQ values from degradation of readily degradable organics initially occurred. RQ then stabilized at slightly lower values, then decreased. Continuous emission of N2O was observed during the RQ decrease. Correlation between nitrification and N2O emission shows that the latter was triggered by nitrification. Mass balances demonstrated that the O2 consumption of nitrification (∼24.8mmol) was slightly higher than that of CO2 emission (∼20.0mmol), indicating that the RQ decrease was caused by the occurrence of nitrification. Results indicate that RQ is a useful index, which not only reflects the bioavailability of organics but also predicts the occurrence of nitrification and N2O emission in forced aerated composting.
authors.affiliation: Research and Education Faculty, Natural Sciences Cluster, Agriculture Unit, Kochi University, B200 Monobe, Nankoku, Kochi, Japan; Japan Science and Technology Agency, CREST, Japan. Electronic address: jm-tsutsuih@kochi-u.ac.jp.
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Tsutsui
authors.affiliation: Research and Education Faculty, Natural Sciences Cluster, Agriculture Unit, Kochi University, B200 Monobe, Nankoku, Kochi, Japan; Japan Science and Technology Agency, CREST, Japan.
authors.forename: Taku
authors.initials: T
authors.lastname: Fujiwara
authors.affiliation: Department of Health Science, School of Allied Health Sciences, Kitasato University, 1-15-1 Kitasato, Sagamihara-Minami, Kanagawa, Japan; Japan Science and Technology Agency, CREST, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Inoue
authors.affiliation: Department of Environmental Engineering, Graduate School of Engineering, Hokkaido University, Kita-13, Nishi-8, Kita-ku, Sapporo, Hokkaido, Japan; Japan Science and Technology Agency, CREST, Japan.
authors.forename: Ryusei
authors.initials: R
authors.lastname: Ito
authors.affiliation: Research and Education Faculty, Multidisciplinary Science Cluster, Life and Environmental Medicine Science Unit, Kochi University, B200 Monobe, Nankoku, Kochi, Japan; Japan Science and Technology Agency, CREST, Japan.
authors.forename: Kazutsugu
authors.initials: K
authors.lastname: Matsukawa
authors.affiliation: Department of Environmental Engineering, Graduate School of Engineering, Hokkaido University, Kita-13, Nishi-8, Kita-ku, Sapporo, Hokkaido, Japan; Japan Science and Technology Agency, CREST, Japan.
authors.forename: Naoyuki
authors.initials: N
authors.lastname: Funamizu
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D058465:Nitrification; D009609:Nitrous Oxide / Q000032:analysis*; D012037:Refuse Disposal / Q000379:methods*; D012987:Soil / Q000737:chemistry*
chemical_list: D000393:Air Pollutants; D012987:Soil; D009609:Nitrous Oxide
keywords: Composting; Nitrification; Nitrous oxide; Respiratory quotient