title: Modeling and parameter estimation of two-phase endogenous respirograms and COD measurements during aerobic digestion of biological sludge.
abstract: Long-term aerobic digestion batch tests were performed on a sludge that contained mainly two fractions, a heterotrophic biomass XH and its endogenous residues XP, which were cultivated in conditions known to favor bio-storage (XSto). The objective was to model the stabilization of the sludge and determine the parameters of the endogenous decay processes, based on simultaneous measurements of the chemical oxygen demand (COD) and oxygen uptake rates (OUR). The respirograms were shown to have a two-phase structure that was describable with activated sludge model 3 (ASM3), but not with ASM1. Comparing the information from the COD and OUR data suggested the presence of two different groups of heterotrophs (XHa and XHb), one that decays with oxygen consumption and another without using O2. A modified ASM3 model was proposed, which was able to fit the OUR and COD data from the digesters, as well as cases from the literature.
authors.affiliation: Centro Interamericano de Recursos del Agua (CIRA), Universidad Autónoma del Estado de México (UAEM), Apdo postal 367, Toluca C.P. 50091, Mexico. Electronic address: c-fa-ll@hotmail.com.
authors.forename: C
authors.initials: C
authors.lastname: Fall
authors.affiliation: Centro Interamericano de Recursos del Agua (CIRA), Universidad Autónoma del Estado de México (UAEM), Apdo postal 367, Toluca C.P. 50091, Mexico.
authors.forename: J A
authors.initials: JA
authors.lastname: Rogel-Dorantes
authors.affiliation: Centro Interamericano de Recursos del Agua (CIRA), Universidad Autónoma del Estado de México (UAEM), Apdo postal 367, Toluca C.P. 50091, Mexico.
authors.forename: E L
authors.initials: EL
authors.lastname: Millán-Lagunas
authors.affiliation: Centro Interamericano de Recursos del Agua (CIRA), Universidad Autónoma del Estado de México (UAEM), Apdo postal 367, Toluca C.P. 50091, Mexico.
authors.forename: C G
authors.initials: CG
authors.lastname: Martínez-García
authors.affiliation: Centro Interamericano de Recursos del Agua (CIRA), Universidad Autónoma del Estado de México (UAEM), Apdo postal 367, Toluca C.P. 50091, Mexico.
authors.forename: B C
authors.initials: BC
authors.lastname: Silva-Hernández
authors.affiliation: Centro Interamericano de Recursos del Agua (CIRA), Universidad Autónoma del Estado de México (UAEM), Apdo postal 367, Toluca C.P. 50091, Mexico.
authors.forename: F S
authors.initials: FS
authors.lastname: Silva-Trejo
mesh_terms: D000332:Aerobiosis; D057919:Biological Oxygen Demand Analysis; D008962:Models, Theoretical; D012722:Sewage
chemical_list: D012722:Sewage
keywords: Accumulating organisms; Aerobic digestion; Endogenous respirograms; Parameter identifiability; Storage