title: Effects of mix ratio, moisture content and aeration rate on sulfur odor emissions during pig manure composting.
abstract: Sulfur compounds in swine manure can cause odor emissions during composting if conditions are not conducive to their rapid oxidation and degradation. In this study, the effects of controllable composting process variables on sulfur odor emissions were investigated. These included pig manure to corn stalk mix ratio (0.7:1, 1.5:1 and 2.2:1dw basis), initial moisture content (60%, 65%, 70% and 75%) and aeration rate (1.0, 2.0, 3.0 and 4.0m(3)m(-3)h(-1)). The compounds measured were carbonyl sulfide, carbon disulfide, hydrogen sulfide, methyl mercaptan, ethyl mercaptan, diethyl sulfide, dimethyl sulfide (Me2S) and dimethyl disulfide (Me2SS). The results showed that total sulfur losses ranged from 3.9% to 18.3% after 26days of composting. Me2S and Me2SS were the primary (>59.61%) sulfur compounds released during this period. After turning, emission rates of both Me2S and Me2SS increased. Emissions of the other six sulfur compounds were low and inconsistent during composting. Within the compost, feedstock mix ratio significantly influenced the concentration of Me2SS, while aeration rate significantly affected Me2S concentration (p<0.05). Moisture content did not have a significant effect on the concentrations of either of these two compounds. Concentrations of sulfur odor compounds were the lowest at the highest aeration rate. Therefore, high aeration rates during the thermophilic phase, especially after turning, are recommended to minimize sulfur odors produced during swine manure composting.
authors.affiliation: College of Resource and Environmental Science, China Agricultural University, Beijing 100193, PR China; Department of Food, Agricultural and Biological Engineering, Ohio Agricultural Research and Development Center, The Ohio State University, Wooster, OH 44691, USA. Electronic address: zangbing12@163.com.
authors.forename: Bing
authors.initials: B
authors.lastname: Zang
authors.affiliation: College of Resource and Environmental Science, China Agricultural University, Beijing 100193, PR China.
authors.forename: Shuyan
authors.initials: S
authors.lastname: Li
authors.affiliation: Department of Food, Agricultural and Biological Engineering, Ohio Agricultural Research and Development Center, The Ohio State University, Wooster, OH 44691, USA.
authors.forename: Frederick
authors.initials: F
authors.lastname: Michel
authors.affiliation: College of Resource and Environmental Science, China Agricultural University, Beijing 100193, PR China. Electronic address: ligx@cau.edu.cn.
authors.forename: Guoxue
authors.initials: G
authors.lastname: Li
authors.affiliation: College of Resource and Environmental Science, China Agricultural University, Beijing 100193, PR China.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Luo
authors.affiliation: College of Resource and Environmental Science, China Agricultural University, Beijing 100193, PR China.
authors.forename: Difang
authors.initials: D
authors.lastname: Zhang
authors.affiliation: College of Resource and Environmental Science, China Agricultural University, Beijing 100193, PR China.
authors.forename: Yangyang
authors.initials: Y
authors.lastname: Li
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D000818:Animals; D002681:China; D004784:Environmental Monitoring; D008372:Manure / Q000032:analysis*; D009812:Odorants / Q000032:analysis*; D013457:Sulfur Compounds / Q000032:analysis*; D034421:Sus scrofa; D018505:Waste Management / Q000379:methods*
chemical_list: D000393:Air Pollutants; D008372:Manure; D013457:Sulfur Compounds
keywords: Aerated static pile; Compost; Dimethyl disulfide; Dimethyl sulfide; Pig manure; Sulfur odor