Search results for " Foaming"
showing 3 items of 3 documents
Foaming in membrane bioreactors: Identification of the causes
2012
Membrane bioreactors (MBRs) represent by now a well established alternative for wastewater treatment. Their increasing development is undoubtedly related to the several advantages that such technology is able to guarantee. Nevertheless, this technology is not exempt from operational problems; among them the foaming still represents an "open challenge" of the MBR field, due to the high complexity of phenomenon. Unfortunately, very little work has been done on the foaming in MBRs and further studies are required. Actually, there is not a distinct difference between conventional activated system and MBR: the main difference is that the MBR plants can retain most Extracellular Polymeric Substan…
The role of EPS in the foaming and fouling for a MBR operated in intermittent aeration conditions
2016
Abstract This work investigates the causes of foaming and fouling in an Intermittent Aerated – Membrane BioReactor (IA-MBR) used for wastewater treatment. The experiment was divided into three periods with different aerated regimes expressed with different t aeration /t cycle ratio (Period I: 60 min/180 min, Period II: 80 min/180 min, Period III: 30 min/90 min). The advanced foaming tests used allow the study of the role of extracellular polymeric substances (EPSs) on foaming and fouling. In general, in the Periods I and II, good correlations between the EPSs and the Modified Scum Index without purification (MSI 0 ) and the Foam Power were observed. The results shown that the filamentous mi…
Il foaming nei sistemi MBR: misure e valutazioni in-situ
2017
Nonostante la tecnologia MBR mostri un grande trend di crescita nel numero di applicazioni in piena scala, rimane ancora poco studiato il fenomeno della formazione di schiume all’interno dei reattori biologici che può provocare non pochi problemi gestionali degli impianti. Quest’aspetto fa sì che il fenomeno è oggi di crescente interesse scientifico, anche a seguito d’ipotesi secondo cui i fenomeni di foaming e fouling potrebbero reciprocamente influenzarsi, considerando i fattori comuni di influenza (EPS, microrganismi filamentosi idrofobici, fisiologia del fango). A tal riguardo viene anche mostrato che la ricerca scientifica condotta in Italia sull’argomento è molto ben avviata, stante l…