Your web browser is out of date.
Update your browser for better security, speed and to get the best experience on this website.
Biological treatment can be aerobic, anoxic or anaerobic depending on whether oxygen is present. Most biological wastewater treatment schemes are aerobic and based on the conventional/classical activated sludge (CAS) process, from which MBRs are adapted.
MBR processes can be configured as immersed or sidestream, and the membranes as flat sheet, hollow fiber or multi-tube. Membranes can also be employed as a 'polishing' step downstream of the biological process, rather than integrated with it as an MBR.
Media processes in wastewater treatment can be based on either agitated or fixed media and be aerated actively or passively, with active aeration applied to submerged media (or 'flooded filters'). Example processes include MBBRs, SAF, BAF and IFAS.
A membrane aerated biofilm reactor (MABR) is an aerobic biological treatment process where the biofilm is fixed to the membrane surface. The membrane additionally permits highly efficient oxygen mass transfer into the biofilm for enhanced biotreatment.
An MBR is a wastewater treatment process where membrane separation is integrated with a biological activated sludge process to completely retain the biological solids (or biomass). The perm-selective membrane replaces the conventional settlement stage.
MBR membranes can take one of three module configurations: flat sheet (FS), hollow fibre (HF) and multitube or multichannel (MT/MC). MBR process take one of two configurations: immersed and sidestream. Biotreatment can be aerobic, anoxic and/or anaerobic.
The design of an MBR system relates to the configuration of the membrane (hollow fibre, flat sheet or tubular), the membrane separation process (immersed or sidestream), and the biological process (aerobic, anaerobic and/or anoxic - often in combination).
MBR OPEX components comprise the energy consumption, staffing requirements, membrane replacement, chemicals consumption, and waste management and disposal. The most significant of these is the energy consumption incurred by membrane and process aeration.
The vast majority of the wastewater treatment capacity provided by MBRs worldwide is for municipal wastewater treatment. Target treated water quality parameters can include nutrients and pathogens, alongside suspended solids, organic carbon and ammonia.
Compared with municipal effluents, industrial effluents tend to have higher and more widely fluctuating concentrations of organic matter than in municipal effluents. The organics are also generally less biodegradable, relected in the lower BOD/COD ratios.
MBR O&M parameters on the membrane side include flux, permeability, membrane aeration rate and physical and chemical cleaning cycle protocols. On the biological side, O&M parameters include the hydraulic and solids retention time and sludge recycle rate.
Membrane bioreactors offer increased removal of most pollutants compared with the conventional activated sludge process. This is because of both intensified biological treatment and filtration of the mixed liquor through a <0.1 µm pore size membrane.
The key challenges imposed by MBR technologies relate largely to the complexities of operating the membrane separation component. These become more evident when the installed pretreatment is insufficiently rigorous, leading to various clogging phenomena.
Explore our MBR directories for technology suppliers, membrane products, consultants and case studies. Contact us if you wish to add a free listing. Please note The MBR Site does not supply equipment – all queries should be directed to our advertisers and companies listed in our directories.
Our MBR Knowledge Hub collates technical information from expert practitioners and operators, specialist companies and academics, all experienced in membrane bioreactor technology. Search our technical features, The MBR Blog and our growing list of research abstracts for information on troubleshooting, case studies, costs, research and more.