Membrane bioreactor materials

Generally, a distinction can be made between membrane bioreactors based on cells performing a desired conversion and processes based on enzymes. In ceU-based processes, bacteria, plant and mammalian cells are used for the production of (fine) chemicals, pharmaceuticals and food additives or for the treatment of waste streams. Enzyme-based membrane bioreactors are typically used for the degradation of natural polymeric materials Hke starch, cellulose or proteins or for the resolution of optically active components in the pharmaceutical, agrochemical, food and chemical industry [50, 51]. In general, only ultrafiltration (UF) or microfiltration (MF)-based processes have been reported and little is known on the application of reverse osmosis (RO) or nanofiltration (NF) in membrane bioreactors. Additionally, membrane contactor systems have been developed, based on micro-porous polyolefin or teflon membranes [52-55]. 

In recent years, membrane bioreactors, bioreactors combined with membrane separation unit have established themselves as an alternative configuration for traditional bioreactors. The important advantages offered by membrane bioreactors are the several different types of membrane modules, membrane structures, materials commercially available. Membrane bioreactors seem particularly suited to carry out complex enzymatic/microbial reactions and/or to separate, in situ, the product in order to increase the reaction efficiency. The membrane bioreactor is a new generation of the biochemical/chemical reactors that offer a wide variety of applications for producing new chemical compounds, for treatment of wastewater, and so on. 

Rosenberger, S., Laabs, C., Lesjean, B., Gnirss, R., Amy, G., Jekel, M. and Schrotter, J.-C. (2006) Impact of colloidal and soluble organic material on membrane performance in membrane bioreactors for municipal wastewater treatment. Water Research, 40(4), 710-720. 

Molecular separation along with simultaneous chemical transformation has been made possible with membrane reactors [17]. The selective removal of reaction products increases conversion of product-inhibited or thermodynamically unfavourable reactions for example, in the production of ethanol from com [31]. Enzyme-based membrane reactors were first conceived 25 years ago by UF pioneer Alan Michaels [49]. Membrane biocatalytic reactors are used for hydrolytic conversion of natural polymeric materials such as starch, cellulose, proteins and for the resolution of optically active components in the pharmaceutical, agrochemical, food and chemical industries. Membrane bioreactors for water treatment were introduced earher in this chapter and are discussed in detail in Chapters 2 and 3. 

Gander M A, Jefferson B and Judd S J (2000), Membrane bioreactors for use in small wastewater treatment plants membrane materials and effluent quality . Water Sci Technol, 41,205-211. 

Juang, R. S., Chung,T. P, Wang, M. L. and Lee, D. J. 2008. Experimental observations on the effect of added dispersing agent on phenol biodegradation in a micropo-rous membrane bioreactor. Journal of Hazardous Materials, 151,746-752. 

Xia, M. and Ying,T. J. 2011. Progress in enzymatic membrane bioreactor A review of research methodology and reaction characteristic. Advanced Materials Research, 236-238,2471-2476. 

Saddoud, A., Sayadi, S. (2007). Application of acidogenic fixed-bed reactor prior to anaerobic membrane bioreactor for sustainable slaughterhouse wastewater treatment. Journal of Hazardous Materials, 149, 700—706. 

Zayen, A., Mnif, S., Aloui, F., Fki, F., Loukil, S., Bouaziz, M., et al. (2010). Anaerobic membrane bioreactor for the treatment of leachates from Jebel Chakir discharge in Tunisia. Journal of Hazardous Materials, 177, 918—923. 

Meng, E, Chae, S.R., Drews, A., Kraume, M., Shin, H.S. Yang, F. (2009) Recent advances in membrane bioreactors (MBRs) membrane fouling and membrane material. Water Research, 43, 1489-1512. 

The reactor feed contained glucose and ammonium chloride as the sources of organic carbon and nitrogeneous component. In addition, the feed contained a small amount of minerals as element nutrition. The experimental membrane bioreactor contained 16 carbon tubes of length 20 cm with inner and outer diameter of 4.7 and 8.9 mm, respectively. The pore size was 2 pm. To enhance the bacterial attachment the shell side surface of the carbon membrane was covered with nonwoven material,... 

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