Combining submerged membrane technology with anaerobic and ...

Introductionutilizes the advantages of a biofilm reactor and which at the same time can handle highloads of particles.The Moving Bed Bioreactor (MBBR) consists in an activated-sludge system wherethe biomass is attached to the carriers suspended in the mixed liquor. These carriers havea great internal surface in order to improve the optimal contact of liquid, oxygen andbiomass. It is in the internal surface where the development of the biofilm takes place. Thistechnology addresses some of the most important challenges of the Water andWastewater industry, such as the upgrading of existing treatment plants and tight nutrientdischarge limits (Frost & Sullivan, 2009).From the combination of this technology with the technology of membranebioreactors is born today a new system called Biofilm Membrane Bioreactor (BF-MBR)also called moving bed membrane bioreactor (MBMBR) (Leikness and Ødegaard, 2007)(figure 1.9). This system would present an alternative to the activated sludge MBR bycombining a biofilm reactor with membrane separation of the suspended solids (BF-MBR),which may reduce the effect of membrane fouling by high biomass concentrations. Themembrane module in this kind of systems is located in a separate chamber from thatcontaining the carriers in order to avoid possible damages in the membrane.MOVING BEDBIOFILM REACTORMEMBRANEREACTORpermeateinfluentSludgeairFigure 1.9. Biofilm Membrane Bioreactor (Leikness and Ødegaard, 2007).BF-MBR process has the potential of operating with volumetric loading rates of 2-8kg COD·m -3·d-1 , higher than those observed in typical MBRs of 1-3 kg COD·m -3·d-1 , andHRTs up to 4 h. Sustainable process operation with membrane fluxes around 50 L·m-2·h-1can be achieved in BF-MBR (Leikness and Ødegaard, 2007), which are much higher than49