Mainly for wastewater treatment by using microfiltration (MF) or ultrafiltration (UF) and again integrating them with a biological process just like a suspended growth bioreactor , a membrane bioreactor (MBR) process is used. As a filter removing the solids which are developed during the biological process, the membranes are employed that offers a clear and pathogen-free product.
Through a fine screen the wastewater is passed through for the removal of big objects which may cause damage to the downstream equipment. After that for the treatment of nitrogenous matter and phosphate it enters an Anoxic Zone for an Aerobic Zone where microorganisms with the help of the oxygen coming out of the FBD will digest the organics matter in the wastewater and clump together as they do so and produce a sludge. Entering the Immersed Membrane Bioreactor, this sludge will get passed via the membrane which will separate the solids and microorganisms from water. The MBR gives the end-user improved process control and much better product water quality.
Usually, MBR technology is applied to those wastewaters with readily biodegradable organic carbon content. MBRs due to the long solid retention times (SRT) that allow for an improved biological treatment over the one from the conventional biological processes.
Waters that contain suspended oil (vegetable or mineral) require pretreatment (e.g. plate separation, dissolved air flotation, or both) in order to protect the membrane.