Membrane Bio Reactor (MBR)

Membrane Bioreactors combine conventional biological treatment (e.g. activated sludge) processes with membrane filtration to provide an advanced level of organic and suspended solids removal. When designed accordingly,these systems can also provide an advanced level of nutrient removal.In anM BR system, the membranes are submerged in an aerated biological reactor. The membranes have

porosities ranging from 0.035 micronsto 0.4 microns(depending on the manufacturer),which is considered between micro and ultra filtration.

This level offiltrationallows for high quality effluent to be drawn through them embranes and eliminates the sedimentation and filtration processes typically used for wastewater treatment. Because the need for sedimentation is eliminated, the biological process can operate at a much higher mixed liquor concentration. This dramatically reduces the process tankage required and allows many existing plants to be upgraded without adding new tanks. To provide optimal aeration and scour around the membranes, the mixed liquor is typically kept in the1.0-1.2%solidsrange, which is 4 times that of conventional plant.

Advantage

• 1. Secondary clarifiers and tertiary filtration processes are eliminated, thereby reducing plant footprint. In certain instances, footprint can be further reduced because other process units such as digesters or UV disinfection canal sobee liminated/minimized(dependent upon governing regulations)
• 2. Can be designed to prolong sludge age, hence lower sludge production.
• 3. High effluent quality.
• 4. High loading rate capability.