title: Volatile fatty acids production from food waste: effects of pH, temperature, and organic loading rate.
abstract: The effects of pH, temperature, and organic loading rate (OLR) on the acidogenesis of food waste have been determined. The present study investigated their effects on soluble chemical oxygen demand (SCOD), volatile fatty acids (VFAs), volatile solids (VS), and ammonia nitrogen (NH4(+)-N). Both the concentration and yield of VFAs were highest at pH 6.0, acetate and butyrate accounted for 77% of total VFAs. VFAs concentration and the VFA/SCOD ratio were highest, and VS levels were lowest, at 45 °C, but the differences compared to the values at 35 °C were slight. The concentrations of VFAs, SCOD, and NH4(+)-N increased as OLR increased, whereas the yield of VFAs decreased from 0.504 at 5 g/Ld to 0.306 at 16 g/Ld. Acetate and butyrate accounted for 60% of total VFAs. The percentage of acetate and valerate increased as OLR increased, whereas a high OLR produced a lower percentage of propionate and butyrate.
authors.affiliation: School of Environment, Tsinghua University, Beijing 100084, China. jianguoj@mail.tsinghua.edu.cn
authors.forename: Jianguo
authors.initials: J
authors.lastname: Jiang
authors.forename: Yujing
authors.initials: Y
authors.lastname: Zhang
authors.forename: Kaimin
authors.initials: K
authors.lastname: Li
authors.forename: Quan
authors.initials: Q
authors.lastname: Wang
authors.forename: Changxiu
authors.initials: C
authors.lastname: Gong
authors.forename: Menglu
authors.initials: M
authors.lastname: Li
mesh_terms: D005232:Fatty Acids, Volatile / Q000096:biosynthesis*; D005502:Food; D006863:Hydrogen-Ion Concentration; D012037:Refuse Disposal; D013696:Temperature
chemical_list: D005232:Fatty Acids, Volatile
keywords: Food waste; Organic loading rate; Temperature; VFA; pH