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What exactly is a membrane bioreactor?

Various sectors have expanded due to the global increase in the human population. The demand for an abundant supply of water and the development of high-quality effluent based on adequate treatment methods has become a requirement. These two critical requirements may be met by using a membrane bioreactor (MBR), thriving as a biological unit for wastewater treatment in eliminating organic and inorganic materials.

 What is a membrane bioreactor?

Membrane bioreactors (MBRs) combine membrane procedures such as microfiltration or ultrafiltration with a biological wastewater treatment process known as activated sludge. It is presently widely used in municipal and industrial wastewater treatment. There are two types of MBRs: submerged membrane bioreactors (SMBR) and side stream membrane bioreactors (SSMB). The membrane is immersed in wastewater inside the biological reactor in the first arrangement. The membrane is situated outside the reactor in the latter version as an extra step following biological treatment.

 What does a membrane bioreactor do?

Membrane Bioreactors are treatment systems that use a perm-selective or semi-permeable membrane in conjunction with a biological process. It combines a membrane technology, such as microfiltration or ultrafiltration, with a suspended growth bioreactor. It is now utilized for municipal and industrial wastewater treatment in plants ranging in size from 10,000 to 80,000 people. Because it is a highly technical solution, expert design and skilled labor are required. Furthermore, it is an expensive but effective therapeutic alternative. Using MBBR technology, it is possible to upgrade old wastewater treatment plants.

Membrane Bioreactors combine classic biological treatment methods (such as activated sludge) with membrane filtration to increase organic and suspended solids removal. These systems, if correctly built, may also allow for improved nutrient removal. An MBBR system’s membranes are submerged in an aerated biological reactor. The membrane porosities range from 0.035 microns to 0.4 microns.

High-quality effluent may be drawn through the membranes at this degree of filtration, eliminating the requirement for sedimentation and filtering processes customarily used in wastewater treatment. Because sedimentation is no longer necessary, the biological process can operate at much higher mixed liquor concentrations.

This considerably minimizes the process tankage required, modernizing many current facilities without installing additional tanks. To provide appropriate aeration and scour around the membranes, the mixed liquid is generally kept in the 1.0-1.2 percent solids range, four times that of a standard plant.


MBR performance may be fully sustained with effective fouling prevention strategies and careful operation. This was discovered following various examinations into critical features of MBRs, including design techniques and the fouling issue. It is an innovative and crucial technology for the next generation.