Combining submerged membrane technology with anaerobic and ...

IntroductionUASB, achieving total nitrogen removal percentages up to 60% and removing up to 95% ofdissolved methane.In this sense, it is important to underline that the presence of dissolved methane,especially at low temperature, represents an important environmental problem in terms ofgreenhouse gas (GHG) emissions of wastewaters treated using methanogenic bioreactors.For low strength wastewaters, dissolved methane might account up to 50% of theproduced methane. The dissolved methane is easily desorbed from the effluents,especially if these are either released in the environment or post-treated using aerobicbioreactors.All the examples mentioned before demonstrate that integration of anaerobicprocesses (in particular methanogenesis) with simultaneous nitrification and denitrificationis possible. Moreover, application of MBR, a very low COD concentration and the level ofnutrients in the effluent (e.g. in the case of water reuse in agriculture, nitrogen eliminationcould be not necessary) allows obtaining a high quality, re-usable effluent, which mightconduce to significant water savings.On the other hand, biogas rich with methane can be produced, depending on thewastewater treated. Relatively high membrane fluxes could be obtained, being higher thanthose applied in the case of AnMBR, and similar to aerobic MBRs.1.7. ReferencesAkram, A., Stuckey, D.C. 2008. Flux and performance improvement in a submerged anaerobicmembrane bioreactor (SAMBR) using powdered activated carbon (PAC). ProcessBiochemistry 43, 93-102.An, Y., Yang, F., Chua, H. C., Wong, F. S., Wu, B. 2008. The integration of methanogenesis withshortcut nitrification and denitrification in a combined UASB with MBR. BioresourceTechnology 99, 3714–3720.An, Y., Wang, Z., Wu, Z., Yang, D., Zhou, Q. 2009. Characterization of membrane foulants in ananaerobic non-woven fabric membrane bioreactor for municipal wastewater treatment,Chemical Engineering Journal 155, 709–715.Artiga, P., Oyanedel, V., Garrido, J.M., Méndez, R. 2005. An innovative biofilm-suspended biomasshybrid membrane bioreactor for wastewater treatment, Desalination 179, 171-179.AWWA-Lyonaisse des eaux. 1998. Tratamiento del agua por procesos de membrana. Ed. McGraw-Hill, Madrid, Spain.Barker DJ, Stuckey DC. 1999. A review of soluble microbial products (SMP) in wastewatertreatment systems. Water Research 33, 3063–82.53