Evolving the Distillation Sequence

The following steps are necessary in establishing a heat integrated distillation sequence 

Establish simple sequences. Using methods described in Chap. 5, sequences of simple columns with low overall vapor load are established. Consideration should not be restricted to the single sequence with the lowest overall vapor load, since many factors need to be considered in finally arriving at the best design. 

Establish the heat integration potential of simple columns. Introduce heat recovery between reboilers, intermediate reboilers, condensers, intermediate condensers, and other process streams. Shift the distillation column pressures to allow integration, where possible, using the grand composite curve to assess the heat integration potential. 

Introduce complex distillation configurations. Introduce prefractionation arrangements (with or without thermal coupling), side-rectifiers, and side-strippers to the extent that operability can be 

The logic behind these three evolutions is explained in Chap. 5. 

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