O'Reilly logo

Separation Process Engineering: Includes Mass Transfer Analysis, Third Edition by Phillip C. Wankat

Stay ahead with the world's most comprehensive technology and business learning platform.

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, tutorials, and more.

Start Free Trial

No credit card required

4.15 Comparisons between Analytical and Graphical Methods

Both the Lewis and McCabe-Thiele methods are based on the CMO assumption. When the CMO assumption is valid, the energy balances are automatically satisfied, which greatly simplifies the stage-by-stage calculations. The reboiler and condenser duties, QR and Qc, are determined from the balances around the entire column. If CMO is not valid, QR and Qc will be unaffected if the same external reflux ratio can be used, but this may not be possible. The exact calculation, which can be done using the methods developed in Chapter 6, may show that a higher or lower L0/D is required if CMO is invalid.

When a programmable calculator or a computer is to be used, the analytical method is more convenient, ...

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, interactive tutorials, and more.

Start Free Trial

No credit card required