title: Treatment of sewage sludge in a thermophilic membrane reactor (TMR) with alternate aeration cycles.
abstract: The management of sewage sludge is becoming a more and more important issue, both at national and international level, in particular due to the uncertain recovery/disposal future options. Therefore, it is clear that the development of new technologies that can mitigate the problem at the source by reducing sludge production is necessary, such as the European Directive 2008/98/EC prescribes. This work shows the results obtained with a thermophilic membrane reactor, for processing a biological sludge derived from a wastewater treatment plant (WWTP) that treats urban and industrial wastewater. Sewage sludge was treated in a thermophilic membrane reactor (TMR), at pilot-scale (1 m(3) volume), with alternate aeration cycles. The experimentation was divided into two phases: a "startup phase" during which, starting with a psychrophilic/mesophilic biomass, thermophilic conditions were progressively reached, while feeding a highly biodegradable substrate; the obtained thermophilic biomass was then used, in the "regime phase", to digest biological sludge which was fed to the plant. Good removal yields were observed: 64% and 57% for volatile solids (VS) and total COD (CODtot), respectively, with an average hydraulic retention time (HRT) equal to 20 d, an organic loading rate (OLR) of about 1.4-1.8 kg COD m(-3) d(-1) and aeration/non aeration cycles alternated every 4 h.
authors.affiliation: Department of Civil Engineering and Architecture, University of Pavia, via Ferrata 1, 27100 Pavia, Italy. Electronic address: mcristina.collivignarelli@unipv.it.
authors.forename: Maria Cristina
authors.initials: MC
authors.lastname: Collivignarelli
authors.affiliation: Department of Civil Engineering and Architecture, University of Pavia, via Ferrata 1, 27100 Pavia, Italy. Electronic address: federico.castagnola@unipv.it.
authors.forename: Federico
authors.initials: F
authors.lastname: Castagnola
authors.affiliation: Department of Civil Engineering and Architecture, University of Pavia, via Ferrata 1, 27100 Pavia, Italy. Electronic address: marco.sordi@unipv.it.
authors.forename: Marco
authors.initials: M
authors.lastname: Sordi
authors.affiliation: Department of Civil, Environmental, Architectural Engineering and Mathematics, University of Brescia, via Branze 43, 25123 Brescia, Italy. Electronic address: giorgio.bertanza@unibs.it.
authors.forename: Giorgio
authors.initials: G
authors.lastname: Bertanza
mesh_terms: D057919:Biological Oxygen Demand Analysis; D019149:Bioreactors; D004867:Equipment Design; D010865:Pilot Projects; D012722:Sewage; D014865:Waste Disposal, Fluid / Q000295:instrumentation* / Q000379:methods*
chemical_list: D012722:Sewage
keywords: Aeration/non aeration cycles; Membrane biological reactor (MBR); Sludge adaptation; Sludge minimization