Membrane filtration module for MBR
The MFM (Membrane Filtration Module) from Alfa Laval is designed to boost efficiency and reduce operating costs for the filtration of biologically treated waste water of both industrial and municipal origin. This membrane filtration solution for membrane bioreactors (MBR) combines the best features from flat sheet and hollow fiber membrane technologies into the unique hollow sheet membrane design offered by Alfa Laval. The MFM offers less fouling, high permeability and low energy consumption
The unique design feature of the gravity operated Alfa Laval Membrane Filtration Module is that it operates with an exceptionally low transmembrane pressure (TMP) – up to 10 times lower than today’s technology - across the entire surface of the membrane. This means that the mixed liquor is not squeezed against the membrane surface which reduces fouling and consequently the need for cleaning.
MBR cost issues solved
Membrane bioreactors (MBR) are today known as the most advanced technology within municipal and industrial waste water treatment. With the MFM module Alfa Laval has addressed the issue of the MBR being a costly and complicated technology to install and operate, due to more complicated plant layout and higher maintenance requirements. In house development and production of the MFM module - combined with long experience within the full range of cross-flow membrane filtration - have made it possible to reduce investment and operating costs.
- lowest air consumption on the market
- fully gravity operated membrane at ultra low TMP, giving ground-breaking simplicity for the total MBR installation
- exceptionally high packing density, resulting in high filtration effect with small required tank footprint
- design that is much less prone to fouling than conventional hollow fiber and flat sheet membrane filtration configurations
- high cleaning efficiency by circulating cleaning liquid through the Membrane Filtration Module – long intervals between cleaning
- membrane materials that are highly resistant to acids, caustic substances and oxidation, for extended service life
How it works
The Alfa Laval Membrane Filtration Module (MFM) for membrane bioreactors consists of standardized packages of hollow sheet membranes placed inside a stainless steel frame fitted with the appropriate connections. These are both taller and wider than anything else currently on the market.
Effective circulation, scouring effect
Mixed liquor flows upwards between the membrane elements while the permeate passes through the membrane sheet. To make sure the liquor circulates effectively, air bubbles are used to create a cross-flow velocity. This also provides a scouring effect. Regardless of configuration, air is only added via one single aerator at the bottom.
Ultra low TMP reduces fouling
The unique Alfa Laval design ensures that permeate (cleaned effluent) is drained from the entire surface of the membrane and emerges at both sides of each membrane element, exiting through connectors at the top of the unit. This means that the pressure drop over the membrane is close to zero and there are no dead spots on the membrane itself. Due to the extremely low TMP, the membranes are significantly less prone to fouling, resulting in a longer service life between replacements.
The Alfa Laval Membrane Filtration Module (MFM) for membrane bioreactors consists of standardized packages of hollow sheet membranes placed inside a stainless steel frame fitted with the appropriate connections.
The MFM module is available in three standard sizes as single, double and triple versions:
- MFM 100 with a membrane area of 154 m² (1658 ft²)
- MFM 200 with a membrane area of 308 m² (3315 ft²)
- MFM 300 with a membrane area of 462 m² (4973 ft²)
Other standard modules of 25 or 50 and 100 m² are available for smaller flows