Fermenter jackets

An ASME 2 1 elliptical heads can ensure an increase in pressure resistance of die vessel. Fermenter jackets (e.g., half-pipe, diameter, or true type) should be constructed to sustain die vessel s rated pressure and, thus, enhance its strength. The construction material is type 316L stainless steel, which features an internal mechanical-polish finish of 2B-mill or 25-Roughness Average (Ra) depending on the nature of the fermentation. 

Scale-Up Fermenters ranging from about two to over 100 hters (0.07-3.5 fP) have been used for research and development, but the smaller sizes provide too httle volume for sampling and are difficult to replicate, whue large vessels are expensive and use too much medium. Autoclavable small fermenters that are placed in a water bath for temperature control are less expensive than vessels with jackets or coils, but much labor is required for handling them. Pressure vessels that... 

The process of fermentation gives off heat, and the tanks may need to be cooled with chilled water coils, with jackets, or by cooling the cellar in which the tanks are located. When fermentation is complete, many beers are now pasteurized, in the same manner as milk (see Section 17.1). The beer is then cooled to just above freezing, filtered and left to age . Before final bottling, kegging or canning it will undergo a fine filtration to improve the clarity. 

The concentration of enzyme is veiy low, about several hundred milligrams per litre in the fermentation broth. Solvent extraction is a suitable process to recover a small amount of enzyme. The chance of some enzyme being intracellular is high, therefore cells are ruptured to liberate enzyme, which can then interact with organic solvents. Figure 7.1 shows a simple diagram for a jacketed fermentation vessel for operation at constant temperature. 

The production of benzylpenicillin is very sensitive to temperature. A lot of metabolic heat is generated and the fermentation temperature has to be reduced by controlled cooling. This heat transfer is achieved by circulating chilled water through banks of pipes inside the vessel (which also serve as baffles) or through external limpet coils on the jacket of the vessel. These coils consist of continuous lengths of pipe welded in a shallow spiral round the vessel. This cooling water system is also used to cool batched medium sterilized in the vessel prior to its inoculation. 

Typically, the manufacture of a batch of biopharmaceutical product entails filling the production vessel with the appropriate quantity of purified water. Heat-stable nutrients required for producer cell growth are then added and the resultant medium is sterilized in situ. This can be achieved by heat, and many fermenters have inbuilt heating elements or, alternatively, outer jackets through which steam can be passed in order to heat the vessel contents. Heat-labile ingredients can be sterilized by filtration and added to the fermenter after the heat step. Media composition can vary... 

Exothermicity is a feature of fermentation and strict control of temperature is necessary to keep the cells growing and the enzymes functioning. Reactors up to 500 liters are equipped with jackets, larger units... 

The experimental crystallizer was a 350-mL jacketed glass unit that was provided with sufficient agitation to keep the contents well mixed. The compositions of the charges to the crystallizer were adjusted by adding the amino acids in predetermined ratios concentrations of the amino acid impurities were maintained in ranges comparable to those found in the recovery and purification of L-isoleucine from industrial fermentation reaction masses. The experiments were divided according to the mode of crystallization ... 

At the start of the batch fermentor operation, the broth must be heated to the fermentation temperature, which is usually in the range of 30-37 °C, by passing steam or warm water through the coil or the outer jacket. 

The rates of heat transfer between the fermentation broth and the heat-transfer fluid (such as steam or cooling water flowing through the external jacket or the coil) can be estimated from the data provided in Chapter 5. For example, the film coefficient of heat transfer to or from the broth contained in a jacketed or coiled stirred-tank fermentor can be estimated using Equation 5.13. In the case of non-Newtonian liquids, the apparent viscosity, as defined by Equation 2.6, should be used. 

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