Scale-up and Operation

Scale-Up and Operation Scale-up of pharmaceutical mixer granulators is difficult because geometric similarity is often not preserved. Kristensen recommends constant relative swept volume ratio... 

Applications Membranes create a boundary between different bulk gas or hquid mixtures. Different solutes and solvents flow through membranes at different rates. This enables the use of membranes in separation processes. Membrane processes can be operated at moderate temperatures for sensitive components (e.g., food, pharmaceuticals). Membrane processes also tend to have low relative capital and energy costs. Their modular format permits rehable scale-up and operation. This unit operation has seen widespread commercial adoption since the 1960s for component enrichment, depletion, or equilibration. Estimates of annual membrane module sales in 2005 are shown in Table 20-16. Applications of membranes for diagnostic and bench-scale use are not included. Natural biological systems widely employ membranes to isolate cells, organs, and nuclei. 

Design, scale-up, and operating problems of some solvent extraction processes have been described in the literature, and make interesting reading for engineers and chemists involved in such operations [1,3,5,10,11,16,36, 40,59,61,82,83]. 

The sodium sulfite oxidation technique has its limitation in the fact that the solution cannot approximate the physical and chemical properties of a fermentation broth. An additional problem is that this technique requires high ionic concentrations (1 to 2 mol/L), the presence of which can affect the interfacial area and, in a lesser degree, the mass-transfer coefficient (Van t Riet, 1979). However, this technique is helpful in comparing the performance of fermenters and studying the effect of scale-up and operating conditions. 

Scaling up and operation of a flash pyrolysis system for bio-oif production and application on the basis of rotating cone technology" (1997-2000). 

Scale-up and Operation As discussed above, scale-up of high-shear mixers is difficult due to complex powder flow patterns, wide variations in shear rates among mixers, and competition among granulation rate processes. Ideally, the following should be preserved with scale-up. 

Scale-up and Operation Spray nozzles suffer from caking on the outside and clogging on the inside. When the nozzle is below the bed surface, fast capture of the liquid drops by bed particles, as well as scouring of the nozzle by particles, prevents caking. Blockages inside the nozzle are also common, particularly for slurries. The nozzle design should be as simple as possible, and provision for in situ cleaning or easy removal is essential. 

Even though the bioreactor itself may not be the most costly piece of process equipment, it determines the technical feasibility of the entire process. The attention paid to bioreactor design, scale-up, and operating parameters reflects its central role in successful commercial ventures. 

Non-Newtonian fluids are frequently encountered in the process industries, especially in biochemical and biotechnological applications. It has been known that the rheological properties of the liquids have profound effects on the performance of bubble columns. The non-Newtonian anomalies create uncertainties in the design, scale-up, and operation of bubble columns. Most analyses and correlations are based on the following two premises, which are not necessarily always applicable ... 

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