To have a more environmental sustainable membrane bioreactor, it is possible to use an hybrid bioreactor in order to enhance, for the same input of energy in the bioreactor, the gaz/liquide mass transfer and the reactional capacity of the bioreactor. You can also, in this type of bioreactor limit the concentration of the activated sludge to 3g/l in order to facilitate the membrane separation and to limit the membrane fouling.

Dear Karan

I think with integration of various processes for various applications we can do it, for example with combination of adsorption and biological wastewater treatment (membrane bioreactor and adsorbents such as PAC or activated carbon) combination of different biological treatment like as membrane bioreactor and moving bed biofilm reactor….or with focusing to water reuse and application of treated water for industrial purpose like boiler or other process…

Use cogeneration to power the blowers and heat to warm the reactor. This enhances biological activity and permeability. It also protects the membranes from cold weather fouling.

http://onlinembr.info/Principles/Temperature%20effect%20on%20flux.htm

http://ieeexplore.ieee.org/xpl/login.jsp?tp=&arnumber=5163021&url=http%3A%2F%2Fieeexplore.ieee.org%2Fiel5%2F5162127%2F5162128%2F05163021.pdf%3Farnumber%3D5163021

http://www.google.com/url?sa=t&rct=j&q=&esrc=s&frm=1&source=web&cd=3&cad=rja&ved=0CD0QFjAC&url=http%3A%2F%2Fwww.trusselltech.com%2Fuploads%2Fmedia_items%2Fmbr-membrane-fouling.original.pdf&ei=Q2dJUtzCLZGp4AOE6IH4Bg&usg=AFQjCNEzeSa2KoOtdKmTicA5VS4xU3rf0Q&sig2=DErw58MZz6eIAaKx9aBJDA

Thank you everyone for your valuable suggestions.

@Nicolas Roche - can you also suggest some hybrid techniques for MBR to enhance make it more sustainable.

@Farshid - After adding adsorbent (Activated Carbon)obviously it will be saturated after sometime for so what to do after that?

@Alexander - cogeneration can be used only if the MBR is AnMBR (Anaerobic MBR)

The AnMBR requirement you stipulate is only if you require the methane to come from the digestion process. Right now MBR technology uses electricity and there is waste heat associated with most of that electricity that now goes unused. All large MBR plants in the US have back up generators that could be cogen units. Perhaps not existing diesel ones but certainly future natural gas ones. Systems that are used for cogen have shown their reliability over back up systems recently in super storm Sandy. It is easier to justify proper maintenance on something you use everyday versus something you might never use.

@ Karan Chavan : Hybrid MBR which combines activated carbon adsorption/desorption, biodegradation by free and immobilized biomass and membrane separation is a possible sustainable technology for WWT. Continuous Bioregeneration could be improved to recover adsorbent properties without any chemical or physical cleaning processes. But the goal is to find the optimal operating conditions (loading rate, retention/contact time, porous properties of the sorbent material, ...).

@Alexander - Thank you keeping things in perspective. Coupling anything with cogen makes it a viable sustainable option.

@Geoffroy - Thank you for your suggestion. The Bio regeneration aspect of the MBR may be one of the key things that may make the system well suited for different waste waters.

Maybe you need to consider a set up that combines a membrane reactor with activated carbon or other type of absorbents. There is an interesting article about it, related to its operation at low temperture: Effect of temperature on the treatment of domestic wastewater with a staged anaerobic fluidized membrane bioreactor (SAF-MBR) system, from R. H. Yoo, J. H. Kim, P. L. McCarty, J. H. Bae