Extractive membrane bioreactors application

Liu W, Howell JA, Amot TC, and Scott JA. A novel extractive membrane bioreactor for treating biorefractory organic pollutants in the presence of high concentrations of inorganics Application to a synthetic acidic effluent containing high concentrations of chlorophenol and salt. / Mem Sci, 2001 181(1) 127-140. 

The chapter focuses on membrane bioreactors where a UF or MF membrane is employed for biomass retention and filtration. However, membrane bioreactors where the membrane provides a support for biofilms are an alternative form of membrane bioreactor for wastewater treatment application. Two processes, in particular, the membrane-aerated biofilm reactor (MABR) and the extractive membrane bioreactor (EMB), have seen significant interest in recent years. Figure 36.4 shows these two technologies schematically. The application of biofilms reactors for wastewater treatment systems is advantageous in view of... 

Application of extractive membrane bioreactor (EMBR) for the treatment ofVOC-laden wastewater. Air stripping oftheVOCs is prevented since VOCs and Oj diffuse into the biofilm (where the biodegradation process occurs) from opposite directions. 

Almeida, J. S., Reis, M. M. and Crespo, J. G. 1999. Development of extractive membrane bioreactors for environmental applications. Environment Protection Engineering, 25,111-121. 

Pervaporation membrane reactors (PVMR) are an emerging area of membrane-based reactive separations. An excellent review paper of the broader area of pervaporation-based, hybrid processes has been published recently [3.1]. The brief discussion here is an extract of the more comprehensive discussions presented in that paper, as well as in an earlier paper by Zhu et al [3.2]. Mostly non-biological applications are discussed in this chapter. Some pervaporation membrane bioreactor (PVMBR) applications are also discussed additional information on the topic can be found in a recent publication [3.3], and a number of other examples are also discussed in Chapter 4. 

In this section, several applications of membrane reactors on the commercial scale will be highlighted as well as some membrane-based processes that have potential for industrial application. Membrane-assisted esterifications and dehydrogenations will be discussed as well as the OTM process for the production of syngas. Additionally, typical membrane bioreactors such as used in the acy-lase process developed by Degussa AG, and membrane extraction systems such as the MPGM system and the Sepracor process are described. 

Membrane bioreactors have applications in fermentation, pharmaceutical production, protein extraction and wastewater treatment (Inloes et al., 1983 Gabelman and Hwang, 1999). Membranes can be used in the recycle loop with other types of reactor, such as CSTR, in which the membrane module is used to separate the cells from the product stream and then recycle the cells back into the reactor. In another arrangement, cells or enzymes can be entrapped on the surface of the membrane or incorporated into the membrane s porous structure. The substrate is fed through the lumen and product leaves the other side of the lumen through the shell side of the module. 

Biomaterials, Synthesis, Fabrication, and Applications Bioreactors Distillation electrochemical Engineering Fluid Dynamics Membrane Structure Membranes, Synthetic (Chemistry) Molecular Hydrodynamics Nano-structured Materials, Chemistry of Pharmaceuticals, Controlled Release of Solvent Extraction Wastewater Treatment and Water Reclamation... 

The use of various membrane configurations coupled with bioreactors has lead to multiple functionality improvements and innovations. Implementation as guard beds, recycle conditioning vessels (with solids separations capabilities), in situ extraction systems, and slipstream (and bypass) reactors for biocatalyst activity maintenance, are but a few important examples representing successful applications when using living systems operating in controlled microenvironments. 

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