Bioreactor systems, specific examples

There have been many simple modifications to airlift bioreactors for specific applications. For example, a novel airlift loop fermenter (schematic unavailable in the literature) utilizes a side arm. The external loop in this integrated system overcomes the problem of ethanol inhibition by continuously stripping ethanol from the fermentation broth and recovering it by condensation. This is suitable for the simultaneous production and recovery of ethanol. ... 

The BOHLM systems, integrating reaction, separation, and concentration functions in one apparatus (bioreactor), attracted great interest in the last few years. Bioreactors combine the use of specific biocatalyst for the desired chemical reactions, with repeated or continuous application of it under very specific conditions. Such techniques were termed hybrid membrane reactors. In biotechnology and pharmacology, these applications are termed hybrid membrane bioreactors or simply bioreactors (see Table 5.13). An example of an experimental setup of the bioreactor system is shown sche-maticaUy in Figs 5.14 and 5.15. 

Continuous steady-state bioreactors [6]. In warm-up example 7, we discovered that for this specific example, it was a better option to arrange two bioreactors of volume V/2 in series instead of one bioreactor of volume V. A company interested in your skUls wants to design a system of bioreactors with a total volume of 500 [L] and get an output substrate concentration lower than 31 [g/L]. 

The coupling of reaction kinetics with transport processes is necessary to develop effective bioreactor systems. Further discussion of this topic is given later in this chapter (see Reacting Systems and Bioreactors and Illustrative Example for reactor design specifications and mass transfer analysis in encapsulation motifs, respectively). Heat and momentum transport are major topics discussed in other chapters in this section of the handbook. Brief comments on the necessity for these studies are presented as here. 

Understanding and mimicking of the cellular transport processes are both challenging and rewarding from scientific and technological point of view. For example in certain inherited diseases (such as cystinuria), specific transport systems are either defective or missing [1]. Cystinuria is a human disease characterized by the absence of a transport system that carries cystine and other amino acids into kidney cells. Kidney cells normally reabsorb these amino acids from the urine and return them to the blood, but a person inflicted with cystinuria develops painful stones from amino acids that accumulate and crystallize in the kidneys. Similarly, there are many technological applications of these transport processes, e.g., bioseparations, bioextractions, and synthetic nano-bioreactors. 

Flow regime identification is dependent on the geometry of the bioreactor. For example, flow regimes in bnbble columns will be different from those identified in stirred-tank bioreactors. In some cases, the experimental techniques used to identify flow regimes are system independent, while in other cases, the technique was developed for a particular geometry. The specific flow regime definitions in common bioreactor types are described in detail in their respective chapters. 

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