EU LIFE PERBIOF PROJECT (A new technology for treating municipal and/or industrial wastewater with low environmental impact)

Conventional suspended biomass reactors (e.g. activated sludge systems), widely used for treating municipal and/or industrial wastewater, have the disadvantage of large area requirement and high surplus biomass production. This explains the great effort being made worldwide to find a replacement for conventional technologies, with innovative ones aimed at lower footprint, better operational flexibility and lower sludge production. In such a contest, the Water Research Institute (IRSA) of the Italian National Research Council (CNR), has been developing a new technology (SBBGR- Sequencing Batch Biofilter Granular Reactor) for treating wastewater pollutants featured by maximum efficiency and minimum sludge production.
SBBGR technology is based on a periodic biofilter in which all the steps of the biological treatment (i.e., carbon removal, nitrogen removal, secondary sedimentation) take place, one after the other, in a same tank instead of moving to a second tank for the continuation of the treatment as in conventional treatment systems. The high effectiveness of such a technology is due to the peculiar characteristics of the biomass that grows into it. In fact, under specific operational conditions, such a biomass grows as granules characterized by very high density (see figure 1), up to 4-5 times higher than that recorded for biomass growing in conventional suspended biomass systems. Such a high biomass density results in a higher biomass concentration (up to 40 kg/m3) with interesting repercussions on treatment capacities and sludge production (almost one magnitude order lower than that commonly reported for conventional systems).
IRSA has extensively applied this technology for treating at laboratory scale different wastewater types. Considering the interesting results obtained at this scale, in 2005, the European Commission has financed within the framework of the LIFE-Environment Programme the transfer to demonstrative scale of SBBGR technology (PERBIOF project: "A new technology for treating municipal and/or industrial wastewater with low environmental impact"). The project, with a term of 3 years, is implemented by IRSA with the cooperation of IRIDE SpA (i.e., on of the biggest Italian multi-utility companies) and Université de Savoie (France). Important objectives of this project are the technological effectiveness and cost-benefits evaluations to be assessed during two demonstration campaigns to be carried-out at a large scale wastewater treatment facility by means of a prototype specifically designed and built for this project (see figure 2). In particular, the first experimental campaign is focussed on municipal wastewater treatment, while the second one on tannery wastewater chosen as representative of industrial wastewater.
The results obtained in the first experimental campaign, during which the prototype was fed with the primary effluent coming from the municipal wastewater treatment plant of Bari, a town located in Southern Italy, showed that the prototype was able to remove 80% of COD, suspended solids and nitrogen even when the minimum hydraulic retention time (i.e., 4 h) was applied. Moreover, a very low sludge production value (i.e., almost one magnitude order lower than that commonly reported for conventional systems) was recorded.
The prototype is currently being used by the second demonstration campaign, i.e., for the treatment of tannery wastewater coming from tannery district of Avellino (Southern Italy). Considering the presence in this wastewater of a relevant fraction of recalcitrant organics, the biological treatment is being integrated with chemical oxidation (performed by ozone) by equipping the prototype with a chemical oxidation unit with the aim of rendering biodegradable the refractory compounds.

For further information about the planned activities and results obtained, please go to:, completely dedicated to PERBIOF project.