Conceptual Process Design Suite User Guide

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For any given design/revamp project there will always be multiple solutions regarding process structure, even when a decision on the technologies to use has been reached (e.g., distillation vs. absorption). The number of alternatives tends to be so large that there is no realistic hope of analyzing them all even at the simplest level.

A classic example of this is found in separation systems for multi-component mixtures as illustrated in the figure below:
For the separation of a ternary mixture using distillation columns, we have only 2 solutions available: the direct and the indirect sequence.As we increase the number of components in the feed to the separation system we witness a combinatorial explosion.

For the example above, a mixture containing five components results in fourteen alternative flowsheets, and a feed with eight components results in four hundred and twenty nine possible configurations.