ABSTRACT
Scale-Up. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 524 19.3 Materials and Methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 528 19.4 Results and Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 529
19.4.1 Contribution to Pressure due to Differences in System Hardware . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 532
19.4.2 Contribution to Pressure due to Membrane Cassette Construction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 534
19.5 Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 537 Appendix: Conversion of Torque and Pressure to Clamping Force . . . . . . . . . 538 Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 538 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 539
Scale-up of ultrafiltration processes is generally considered straightforward due to the availability of membrane cassettes that are linearly scalable. The fluid
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is to be upon scale-up, which is achieved by geometric similarity of the membrane cassettes at the two scales, and appropriate scale-up of fluid volumes and flow rates. While this is true for most ultrafiltration processes, such simple rules are not adequate in the case of highly viscous process streams and/or at high flow rates due to the greater demand placed on pressure drops in the system. This chapter illustrates some of the issues that may be encountered in such a scale-up, using a case study of ultrafiltration of a bacterial polysaccharide exhibiting such characteristics.
