title: Particle-Scale Modeling of Methane Emission during Pig Manure/Wheat Straw Aerobic Composting.
abstract: Inefficient aerobic composting techniques significantly contribute to the atmospheric methane (CH4) levels. Macro-scale models assuming completely aerobic conditions cannot be used to analyze CH4 generation in strictly anaerobic environments. This study presents a particle-scale model for aerobic pig manure/wheat straw composting that incorporates CH4 generation and oxidation kinetics. Parameter estimation revealed that pig manure is characterized by high CH4 yield coefficient (0.6414 mol CH4 mol(-1) Cman) and maximum CH4 oxidation rate (0.0205 mol CH4 kg(-1) VS(aero) h(-1)). The model accurately predicted CH4 emissions (R(2) = 0.94, RMSE = 2888 ppmv, peak time deviation = 0 h), particularly in the self-heating and cooling phases. During mesophilic and thermophilic stages, a rapid increase of CH4 generation (0.0130 mol CH4 kg(-1) VS h(-1)) and methanotroph inactivation were simulated, implying that additional measures should be performed during these phases to mitigate CH4 emissions. Furthermore, CH4 oxidation efficiency was related to oxygen permeation through the composting particles. Reducing the ambient temperature and extending the aeration duration can decrease CH4 emission, but the threshold temperature is required to trigger the self-heating phase. These findings provide insights into CH4 emission during composting and may inform responsible strategies to counteract climate change.
authors.affiliation: Laboratory of Biomass & Bioprocessing Engineering, College of Engineering, China Agricultural University , (East Campus), Box 191, Beijing 100083, China.
authors.forename: Jinyi
authors.initials: J
authors.lastname: Ge
authors.affiliation: Laboratory of Biomass & Bioprocessing Engineering, College of Engineering, China Agricultural University , (East Campus), Box 191, Beijing 100083, China.
authors.forename: Guangqun
authors.initials: G
authors.lastname: Huang
authors.affiliation: Laboratory of Biomass & Bioprocessing Engineering, College of Engineering, China Agricultural University , (East Campus), Box 191, Beijing 100083, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Huang
authors.affiliation: Laboratory of Biomass & Bioprocessing Engineering, College of Engineering, China Agricultural University , (East Campus), Box 191, Beijing 100083, China.
authors.forename: Jianfei
authors.initials: J
authors.lastname: Zeng
authors.affiliation: Laboratory of Biomass & Bioprocessing Engineering, College of Engineering, China Agricultural University , (East Campus), Box 191, Beijing 100083, China.
authors.forename: Lujia
authors.initials: L
authors.lastname: Han
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D000818:Animals; D057231:Climate Change; D007700:Kinetics; D008372:Manure / Q000032:analysis; D008697:Methane / Q000032:analysis* / Q000737:chemistry; D008962:Models, Theoretical; D012987:Soil / Q000737:chemistry; D034421:Sus scrofa; D014908:Triticum; D018505:Waste Management / Q000379:methods*
chemical_list: D000393:Air Pollutants; D008372:Manure; D012987:Soil; D008697:Methane