Biological Treatment of Wastewater

Membrane bioreactors have been widely used in the biological treatment of wastewater. The membranes used in this type of technology are produced from synthetic organic or inorganic materials. However membranes can also be formed from the deposition of solid particles colloids polymeric materials as well as microbial cells and flocs on an inert support during the filtration process and when coupled to a bioreactor they become a single system called a Dynamic Membrane Bioreactor (DMBR). This type of bioreactor while retaining the solids and microorganisms present in the system removes organic material that is easy and difficult to degrade which reduces treatment costs and makes it advantageous over conventional membrane bioreactors (BRM). In Brazil this technology is relatively new and still little explored. Therefore this review aims to evaluate the performance of BRMD's in anaerobic wastewater treatment systems. In addition to the advantages and disadvantages of this type of system compared to conventional BRMs (micro- and ultrafiltration) the phenomena of BRMD are described.