Page 396 - Analysis, Synthesis and Design of Chemical Processes, Third Edition
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boundary.
When the boundary is curved, there are more options for separation sequences. This is because the only
requirement is that the distillate and bottoms product from a column be in the same region. The feed can
lie in a different region. Also, if a boundary is curved, the product streams from a multiple-column
arrangement may lie in a region across the boundary. Therefore, a column such as the one illustrated in
Figure 12.12 is feasible. Example 12.3 shows how this feature can be exploited.
Figure 12.12 Feasible Column Operation with Curved Boundary
Example 12.3
For the system illustrated in Figure 12.9(b), with a feed mixture of B and C (denoted F), conceptualize a
distillation sequence that produces “pure” B and C using a light entrainer, A.
One possible sequence is illustrated in Figure E12.3.
Figure E12.3 Process Configuration and Residue Curve Map for Example 12.3
