Bioprocess pressure

BioProcess stainless-steel columns are fixed bed height columns designed for the most stringent requirements in the routine production of biopharmaceuticals. Wetted materials include stainless steel, polypropylene, and EPDM. The BPSS series may be operated at pressures up to 3 bar (0.3 MPa) and are supplied with sanitary fittings of 10 or 22 mm i.d. The available column sizes and specifications for the BPSS column series are given in Table 2.18. 

When compared to purely chemical synthesis, bioprocesses are operated under relatively mild conditions and in aqueous solvents they are essentially low temperature processes with operating temperatures usually below 40°C. The pH of most bioprocesses is between 6 and 8 and the pressure is usually one atmosphere. Under these conditions, substrates (eg oxygen) can be poorly soluble in water, which may limit productivity. Since reactions can generate considerable amounts of heat, waste heat generated during bioprocesses often has to be adequately dissipated to ensure high temperatures do not damage enzymes or cells. 

Continuous and detailed knowledge of process conditions is necessary for the control and optimization of bioprocessing operations. Because of containment and contamination problems, this knowledge must often be obtained without sampling the process stream. At present, conditions such as temperatme, pressure, and acidity (pH) can be measured rapidly and accurately. It is more difficult to monitor the concentrations of the chemical species in the reaction medium, to say nothing of monitoring the cell density and intracellular concentrations of hundreds of compounds. 

In all of the above equations, is assumed to be constant and uniform throughout the flow field. In most items of bioprocess equipment, however, there is a spatial distribution of energy dissipation. The definition of an average or a maximum energy dissipation rate is notoriously difficult in the case of bioprocess equipment such as high pressure homogenisers, centrifuges, pumps and microfiltration units which all have complex flow fields. 

Hamdi, M., Blanc, P.J., and Goma, G., A new process for red pigment production by Monascus purpureus culture on prickly pear juice and the effect of partial oxygen pressure. Bioprocess Eng., 17, 75, 1995. 

High pressure homogenizers are especially suitable for the emulsification processes in the food, pharmaceutical and bioprocess industries. A general disadvantage of these type of reactors is that there is no precise control over the cavitationally active volume and the magnitude of the pressure pulses that will be generated at the end of the cavitation events (cavitational intensity), unless the valve seat designs are substantially modified. 

Having seen the number of papers devoted to bioprocess analyses utilizing vibrational spectroscopy, it cannot be considered an experimental tool any longer. Manufacturers are responding to pressure to make their instruments smaller, faster, explosion-proof, lighter, less expensive, and, in many cases, wireless. Processes may be followed in-line, at-line, or near-line by a variety of instruments, ranging from inexpensive filter-based to robust FT instruments. Raman, IR, and NIR are no longer just subjects of feasibility studies they are ready to be used in full-scale production. 

Norton, T., Sun, D. -W. (2008). Recent advances in the use of high pressure as an effective processing technique in the food industry. Eood Bioprocess. Technol., 1, 2-34. 

Mild reaction condition The reaction conditions for bioprocesses are mild. The typical condition is at room temperature, atmospheric pressure, and fairly neutral medium pH. As a result, the operation is less hazardous, and the manufacturing facilities are less complex compared to typical chemical processes. 

NCE has also been used to determine various bioprocesses, generally performed by measuring fundamental physical and chemical parameters, such as temperature, pressure, pH, and reaction rates. NCE has also been used to study some chemical reactions on chip followed by the separation of reaction products. 

Thermal Mass Flowmeters The trend in the chemical process industries is toward increased usage of mass flowmeters that are independent of changes in pressure, temperature, viscosity, and density. Thermal mass meters are widely used in semiconductor manufacturing and in bioprocessing for control of low flow rates (called mass flow controllers, or MFCs). MFCs measure the heat loss from a heated element, which varies with flow rate, with an accuracy of 1 percent. Capacitance probes measure the dielectric constant of the fluid and are useful for flow measurements of slurries and other two-phase flows. 

Proteins are macromolecules (molecular weights from about 5000 to 106 [3]). There are thousands of different types of proteins, each with a particular biological function, often extremely specific. Thus, a particular enzyme will often recognize only one or a very narrow class of compounds as reactants and catalyze reaction of those to particular products. Other enzymes, typically those that catalyze hydrolysis or other degradative reactions, recognize a particular bond type but will act upon a broad class of reactants (substrates). These protein catalysts typically operate effectively at ambient temperature and pressure. Unique catalytic capabilities give enzymes their niche in bioprocessing. 

The almost non-corrosive conditions (low temperature, neutral pH, atmospheric pressure) of most bioprocesses have the advantage that there is much slower destruction of the reaction vessels, which means financial depreciation over a much longer period of time. Indeed, it has been estimated that biotechnological reactors have a life span three times that of chemical reactors. The relatively mild conditions of bioprocesses are also favourable compared with chemical sjmthesis, where the high temperatures and pressures can incur considerable costs. 

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