Search results for "sanitari"
showing 10 items of 639 documents
La corretta progettazione e gestione degli impianti, come garanzia di protezione per l’ambiente
2019
rappresentano requisiti essenziali per la protezione dell’ambiente. In particolare, la conoscenza dei fenomeni che si instaurano al loro interno, perlopiù di natura biologica, è di fondamentale importanza per la buona riuscita del processo depurativo, sia che si tratti di impianti a tecnologia convenzionale, quali i CAS (Conventional Activated Sludge), o avanzate, quali gli MBR (Membrane BioReactor). Il verificarsi di una disfunzione, a seconda della sua gravità, può comportare il superamento dei limiti previsti per lo scarico per un certo periodo di tempo, causando gravi conseguenze ambientali, nonché un danno economico che deriverebbe sia dall’applicazione di sanzioni amministrative, cons…
BioMAc 2013. I bioreattori a membrana per la depurazione delle acque reflue
2013
Foaming in membrane bioreactor: identification of the causes
2012
The biological foaming was related to the metabolism of certain microorganisms that synthesize and excrete hydrophobic compounds. Recently, by the attention of many researchers the biological foaming in the MBR has attracted, because MBR foam has been also observed in the absence of foam-forming microorganisms, contrarily to conventional activated sludge systems. In this paper the authors investigate the role of EPS and filamentous bacteria analyzing different samples from different MBR pilot plants. In particular, in order to define the macroscopic features and the role of EPS and filamentous bacteria a modified Scum Index (MSI) test was applied. Further a multiple classification of SI was…
Criteri di progettazione dei bioreattori a membrana
2013
Evaluation of biomass activity in membrane bioreactors by means of respirometric techniques
2016
The paper reports the main results of a respirometric experimental survey carried out on several membrane bioreactor pilot plants, characterized by different pilot plant layouts as well as operational conditions. The main aim was to assess the influence of specific conditions on biokinetic/stoichiometric parameters. In particular, the respirometric tests were specifically aimed at investigating the activity of both heterotrophic and autotrophic bacterial species. The achieved results showed that the plant configuration and the features of the feeding wastewater and operational conditions determine significant variation of the kinetic coefficients. The respirometric analysis was confirmed to…
Analisi sperimentale e modellistica di formazione del fouling delle membrane nei sistemi MBR
2012
Greenhouse gas emissions from membrane bioreactors: analysis of a two-year survey on MBRs
2017
The study aims at evaluating the nitrous oxide (N2O) emission from membrane bioreactors (MBRs) for wastewater treatment. With this regards two-years of experimental activities were performed. More specifically, the study investigates the N2O emissions considering multiple influential factors: i. configurations (i.e., sequential batch- SB-MBR; pre-denitrification - DN-MBR; University Cape Town, UCT-MBR and UCT moving bed biofilm reactor, UCT-MB-MBR); ii. wastewater composition (municipal or industrial); iii. Plant operational conditions (i.e., sludge retention time, SRT, carbon-to-nitrogen ratio, C/N, hydraulic retention time, HRT); iv. and membrane modules. Among the overall analysed config…
Removal of carbon and nutrients from wastewater in a moving bed membrane biofilm reactor: the influence of the sludge retention time
2016
A University of Cape Town (UCT) pilot plant combining both membrane bioreactor (MBR) and moving bed biofilm reactor (MBBR) technology was monitored. Three experimental Phases were carried out by varying the mixed liquor sludge retention time (SRT) (indefinite, 30 and 15 days, respectively). The system performance has been investigated during experiments in terms of: organic carbon, nitrogen and phosphorus removal, biokinetic/stoichiometric constants, membrane fouling tendency and sludge dewaterability. The observed results showed that by decreasing the SRT the UCT pilot plant was able to maintain very high total COD removal efficiencies, whilst the biological COD removal efficiency showed a…
High salinity slops treatment through a biofilm-MBR inoculated with halophilic bacteria
2010
Oily wastewater generated, in amounts of millions of tons per year, by ships mainly in engine-rooms (bilge waters) and by washing oil tanks (slops) create a major disposal problem throughout the world because of the persistence and accumulation of xenobiotic compounds in the environment. The high salinity levels (up to 25.000 p.p.m.) and the pollutants concentration limit the chances of discharge into the sewer systems and address the disposal to the sea. This situation severely lowers the discharge limits for most of the “sensible” parameters, such both COD and hydrocarbons. Slops are usually treated by ASP with pretreatment of oil/water separation. There are limited investigations on the …
Predictors of short- and long-term adherence with a Mediterranean-type diet intervention: the PREDIMED randomized trial.
2016
Background: Dietary intervention success requires strong participant adherence, but very few studies have examined factors related to both short-term and long-term adherence. A better understanding of predictors of adherence is necessary to improve the design and execution of dietary intervention trials. This study was designed to identify participant characteristics at baseline and study features that predict short-term and long-term adherence with interventions promoting the Mediterranean-type diet (MedDiet) in the PREvencion con DIeta MEDiterranea (PREDIMED) randomized trial. Methods: Analyses included men and women living in Spain aged 55-80 at high risk for cardiovascular disease. Part…