title: Early warning indicators for monitoring the process failure of anaerobic digestion system of food waste.
abstract: To determine reliable state parameters which could be used as early warning indicators of process failure due to the acidification of anaerobic digestion of food waste, three mesophilic anaerobic digesters of food waste with different operation conditions were investigated. Such parameters as gas production, methane content, pH, concentrations of volatile fatty acid (VFA), alkalinity and their combined indicators were evaluated. Results revealed that operation conditions significantly affect the responses of parameters and thus the optimal early warning indicators of each reactor differ from each other. None of the single indicators was universally valid for all the systems. The universally valid indicators should combine several parameters to supply complementary information. A combination of total VFA, the ratio of VFA to total alkalinity (VFA/TA) and the ratio of bicarbonate alkalinity to total alkalinity (BA/TA) can reflect the metabolism of the digesting system and realize rapid and effective early warning.
authors.affiliation: Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Li
authors.affiliation: Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China.
authors.forename: Qingming
authors.initials: Q
authors.lastname: He
authors.affiliation: Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China.
authors.forename: Yunmei
authors.initials: Y
authors.lastname: Wei
authors.affiliation: Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China.
authors.forename: Qin
authors.initials: Q
authors.lastname: He
authors.affiliation: Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China. Electronic address: 505792003@qq.com.
authors.forename: Xuya
authors.initials: X
authors.lastname: Peng
mesh_terms: D000693:Anaerobiosis; D001639:Bicarbonates / Q000032:analysis; D001673:Biodegradation, Environmental; D019149:Bioreactors; D001709:Biotechnology / Q000379:methods*; D005232:Fatty Acids, Volatile / Q000032:analysis; D005502:Food; D006863:Hydrogen-Ion Concentration; D012037:Refuse Disposal / Q000379:methods*; D014866:Waste Products
chemical_list: D001639:Bicarbonates; D005232:Fatty Acids, Volatile; D014866:Waste Products
keywords: Anaerobic digestion; Early warning indicators; Food waste; Organic overloading; Process stability