The Heat Integration Characteristics of Evaporators

Evaporation processes usually separate a single component (typically water) from a nonvolatile material. As such, it is good enough in most cases to assume that the vaporization and condensation processes take place at constant temperatures. 

As with distillation, the dominant heating and cooling duties associated with an evaporator are the vaporization and condensation duties. As with distillation, there will he other duties associated with the evaporator for heating or cooling of feed, product, and condensate streams. These sensible heat duties will usually be small in comparison with the latent heat changes. 

Like distillation, evaporation can be represented as a box. This again assumes that any heating or cooling required by the feed and concentrate will be included with the other process streams in the grand composite curve. 

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