title: Effects of the support material addition on the hydrodynamic behavior of an anaerobic expanded granular sludge bed reactor.
abstract: As a support material, zeolite can be used to promote the granulation process due to its high settable property and the ability to retain biomass on its surface. The present paper reports on the influence of zeolite addition on the hydrodynamic behavior of an expanded granular sludge bed reactor (EGSB). Different models were applied to fit the flow pattern and to compare EGSB hydrodynamic performance with and without the addition of zeolite. The experimental data fit the tanks in a series model for zeolite bed height of 5cm and upflow velocity of 6m/hr. Higher axial dispersion degree (D/uL) was obtained at lower heights of zeolite. The real hydraulic retention time (HRTr) was increased with both increased zeolite bed height and increased upflow velocity. The short-circuit results for 5cm of zeolite bed and 6, 8 and 10m/hr upflow velocity were 0.3, 0.24 and 0.19 respectively, demonstrating the feasibility of using zeolite for a proper hydrodynamic environment to operate the EGSB reactor. The presence of zeolite resulted in the higher percentage values of dead zones, ranging from 12% to 24%. Zeolite addition exerted a positive effect on the hydrodynamics pattern for this technology being advantageous for the anaerobic process because of its possible contribution to better biofilm agglomeration, granule formation and substrate-microorganism contact.
authors.affiliation: Institute of Animal Science, San José de las Lajas, Mayabeque, Cuba.
authors.forename: Tania
authors.initials: T
authors.lastname: Pérez-Pérez
authors.affiliation: Department of Chemical Engineering, Federal University of Sao Carlos, Brazil.
authors.forename: Gleyce Teixeira
authors.initials: GT
authors.lastname: Correia
authors.affiliation: Department of Chemical Engineering, Federal University of Sao Carlos, Brazil.
authors.forename: Wu Hong
authors.initials: WH
authors.lastname: Kwong
authors.affiliation: Process Engineering Centre, Instituto Superior Politécnico José Antonio Echeverría (Cujae), 11901, 114 Street, Marianao, Havana, Cuba.
authors.forename: Ileana
authors.initials: I
authors.lastname: Pereda-Reyes
authors.affiliation: Study Centre of Renewable Energy Technologies, Instituto Superior Politécnico José Antonio Echeverría (Cujae), 11901, 114 Street, Marianao, Havana, Cuba. Electronic address: deny@ceter.cujae.edu.cu.
authors.forename: Deny
authors.initials: D
authors.lastname: Oliva-Merencio
authors.affiliation: Biological Processes Laboratory, Center for Research, Development and Innovation in Environmental Engineering, São Carlos School of Engineering, University of São Paulo, Engenharia Ambiental - Bloco 4-F, Av. João Dagnone, 1100 - Santa Angelina, 13.563-120 São Carlos, SP, Brazil.
authors.forename: Marcelo
authors.initials: M
authors.lastname: Zaiat
mesh_terms: D000693:Anaerobiosis; D019149:Bioreactors; D057446:Hydrodynamics; D008962:Models, Theoretical; D012722:Sewage; D014865:Waste Disposal, Fluid / Q000379:methods*
chemical_list: D012722:Sewage
keywords: Anaerobic digestion; Axial dispersion degree; EGSB reactor; Hydrodynamics; Upflow velocity; Zeolite