Fermenter design principles

The focus of this entry is limited to the design of aerobic fermenters, i.e., stirred tank and concentric tube airlift fermenters, which are commonly utilized in the bioprocessing industries. Design principles and the basic calculations are described with a couple of industrial examples. Readers with a limited background in mixing technology are referred to the gas-liquid contactor entry of this encyclopedia for a more comprehensive understanding of fluid flow and mass transfer characteristics in stirred tank reactors and bubble columns. 

Similar in principle to chemostat configuration except the cells are retained within the fermenter and roller bottles using inline or external cell separation devices. The hollow fiber filter allows continuous separation of cells from tissue culture fluid containing products. In this configuration, the recombinant product is often designed to be excreted into medium allowing it to be collected in perfusate. 

The cocoa and chocolate consumed by the American market are produced by a relatively small number of American and Dutch manufacturers who start with the dried, fermented beans. Current manufacturing practice uses improved machine design and extended automatic control in accord with modern principles of chemical engineering, but it is based solidly on the traditional process, little modified during the last century. 

Bhave RR. Cross-flow filtration. In Fermentation and Biochemical Engineering Handbook—Principles, Process Design, and Equipment, 2nd edition, eds., Vogel HC and Tadaro CL, WiUiam Andrew/Noyes, West Woods, New Jersy, 1997, pp. 271-347. 

An evaporator in a chemical plant or a fermentation operation is a highly-engineered piece of processing equipment in which evaporation takes place. The process and mechanical computations that are required to properly design an evaporator are many and very sophisticated, but the basic principles of evaporation are relatively simple, and it is these concepts that the engineer or scientist involved in fermentation technology should comprehend. 

Vogel, H, C, Fermentation and Biochemical Engineering Handbook Principles, Process Design, and Equipment, Noyes Publications, Park Ridge, New Jersey, 1983,... 

The bioreactor is the central point of a fermentation process. It is here that the biotransformation takes place, that a raw material is turned into a desired and valued product Optimization of the rate of formation and yield of product within the bioreactor is a key part of optimizing the production process. Although the field of bioreactor design for submerged liquid fermentation systems is well developed, many of the principles cannot be directly translated to SSF systems. Solid beds and liquid broths are different solid beds are not as easy to mix as liquid broths, and due to poor heat transfer properties of solid substrate beds, heat removal is much more difficult in SSF than it is in SLF. 

Nielsen, J., ViUadsen, J., Liden, G., 2011. Design of fermentation processes, in Bioreaction Engineering Principles. Springer, New York, pp. 383-458. http //link.springer.coinybook/10.1007 %2F978-1-4419-9688-6 (accessed May 18, 2016). 

Industrial fermentation plants consist of three main sections preparation, fermentation, and product recovery. The preparation section usually contains operations such us medium preparation and sterilization and inoculum propagation. The fermentation section is the heart of the plant where the transformation of raw material into products takes place. The product recovery section encompasses the downstream operations needed to obtain the product of interest with the required purity (Reisman 1988). In the design of fed-batch and batch fermentation plants, one faces the problem of figuring out the adequate combination of the number and size of fermenters to be used to meet the desired production schedule. In principle, the problem has an infinite number of solutions because for any given fermenter size, a number of units of that size will do the work. Nevertheless, not all solutions are equal from an economic standpoint (Simpson et al. 2005). 

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