NOTA! Questo sito utilizza i cookie e tecnologie simili.

Se non si modificano le impostazioni del browser, l'utente accetta.


Francesco Pirozzi, Mentore Vaccari



Membrane Biological Reactors (MBRs) derive from the coupling of traditional activated sludge processes with filtration on micro- or ultra-porous membranes. The major advantages of this solution are due to the absence of sedimentation downstream and, thus, the elimination of all the operational constraints related to that process. The replacement of sedimentation with membrane filtration entails: a considerable reduction of area occupied by the wastewater treatment plant, due to both the elimination of sedimentation units and the increase of concentration of suspended solids in the biological reactors; the possibility of operating the biological process even with significative hydraulic load fluctuations (since the sludge age and the hydraulic retention time are completely independent); lower production of surplus activated sludge; the elimination of problems due to bed sedimentation properties of activated sludge usually present in conventional activated sludge planta; the great improvement of the effluent quality characteristics, which are compatible with the potential reuse of the treated water (Andreottola, 2015).
The design and operation of MBR systems involve the need to take into account various aspects, which, if undervalued, can reflect negatively on performances and management costs: maximum and sustainable flows of permeate; adequate preliminary treatments (to remove coarse and abrasive materials); membrane fouling and cleaning strategies; aeration and energy consumption.
Although first cases of biological processes combined with membrane filtration were built in the 70s, modern MBR systems were developed from the late 80s, when they were used in small-scale treatment plants.
Over the past two decades years, the significant reduction of both membrane cost and energy consumption, new MBR installations have been growing rapidly in the world (Judd, 2011). Information provided by membrane manufacturers leads to estimate that about 260 MBR plants are nowadays present in Italy, mainly in the north of the country. Most of the plants are equipped with flat sheet membranes, used especially in the treatment of industrial wastewater, while hollow fiber membranes are mostly used in big urban wastewater treatment plants. Moreover, hybrid membranes have recently appeared in the national market (Vaccari, 2016).
MBRs are a proven but recent technology, and there is little information about the issues related to their management. 
For this reason, the working group “Management of wastewater treatment plants”, which has been working at the University of Brescia since 1998, launched in 2013 a sub-group aimed to study and spread knowledge on good practices of MBR management in order to avoid the misuse of such technology (which would lead to unsatisfying performances) and support its development (with useful information to membrane manufacturers and plant operators). The activities of the sub-group - which organized two conferences and wrote a book (being published soon) on the operation of MBR treatment plants - on the one hand has confirmed an increasing interest in the MBR plants, on the other hand has shown that some operational aspects must be improved. For this reason, together with the sanitary engineering research groups of the University of Naples “Federico II”, the University of Salerno and the University of Palermo - which have been conducting researches on MBRs for several years and have organized since 2012 a specific annual course entitled BIOMAC - it was decided to set up an “Observatory on MBR treatment plants in Italy”.
The Observatory develops and promotes technical and scientific activities, training courses, seminars, workshops, conferences to encourage the study and dissemination of knowledge and experience about the design, construction and operation of MBR plants. In particular the Observatory:
• monitors the spread of MBR plants in Italy;
• monitors the efficiency and reliability of those plants from technical, environmental and economic perspectives;
• notes the judgment of the managers;
• updates about news on technological and operational aspects;
• disseminate information on the status and on possible developments of the sector;
• publishes an annual report on MBR plants.

The activities of the Observatory are open to anyone interested in MBRs: researchers, plant operators, representatives of public authorities, professionals, companies operating in the water treatment sector. Detailed information about the Observatory can be requested by e-mail to Questo indirizzo email è protetto dagli spambots. È necessario abilitare JavaScript per vederlo.Questo indirizzo email è protetto dagli spambots. È necessario abilitare JavaScript per vederlo..">.


Sei qui: Home Uncategorised n. 3-2017 Pirozzi et al.