New Energy-efficient Hollow-Fiber Membrane Filter for MBR Systems

Mitsubishi Rayon Co., Ltd. (“MRC”) has developed a space-saving, energy-efficient new hollow-fiber membrane product “Sterapore” for the Membrane Bioreactor* (“MBR”) system. Production is scheduled to begin in 2013. 
 
The membrane separation process eliminates a sedimentation tank and allows high volumetric loading, resulting in a smaller footprint and higher effluent quality compared to conventional activated sludge process. These advantages have led to their widespread use in recent years in sewage and wastewater-treatment facilities worldwide. However, there is growing concern about the life-cycle costs of MBR systems, and reduced energy consumption is now sought.
 
MRC has been working to reduce the cost of power for the aeration required for the physical cleaning of the membrane surface, which accounts for the majority of the energy consumption cost of MBR systems. The new technology does this by reducing the amount of aeration needed whilst maintaining high filtration flux. As a result of repeated verification testing at sewage treatment facilities in Singapore in a joint research project with the Singapore Public Utilities Board from January this year, it was possible to cut the power used for aeration for membrane cleaning by 70% compared with MRC’s existing products. Because of this, it is expected that this MBR system will cut energy consumption per unit of treated water by 30% compared with existing products.
 
* Membrane Bioreactor:
A processing method of municipal and industrial wastewater as a combination of the conventional activated sludge process together with a membrane filtration step to separate solids and liquids.