Anaerobic dynamic membrane bioreactor applied to wastewater treatment: a review

Membrane bioreactors have been widely used in biological wastewater treatment. The membranes used in this type of technology are produced from organic or inorganic materials. However, membranes can also be formed from the deposition of solid particles, colloids, and polymeric materials, as well as microbial cells and flocs, on an inert support during the filtration process. When coupled to a bioreactor, they establish a unique system called a dynamic membrane bioreactor (DMBR). This type of bioreactor, while retaining the solids and microorganisms present in the system, removes both easy and difficult-to-degrade organic material, which reduces treatment costs and makes it advantageous compared to conventional membrane bioreactors (MBRs). In Brazil, this technology is relatively new and still little explored. Therefore, the present study aims to evaluate the DMBR's performance in anaerobic wastewater treatment systems. In addition to the advantages and disadvantages presented by this type of system compared to conventional MBRs (micro and ultrafiltration), the fouling phenomenon, its implications, and the theories that explain the formation of the dynamic layer are described. Finally, some challenges that still need to be overcome in the use of this technology are pointed out in order to be affirmed as a safe and robust tool for the biological treatment of domestic and industrial wastewater.