Heat-Pump Efficiency in Acetone-Methanol Extractive Distillation Depending on Feed Composition

The application of heat pumps in extractive distillation is studied on the example of the acetone–methanol mixture. The dependence of the efficiency on the feed mixture composition is investigated. It is found that the most effective in the whole range of feed compositions is the scheme with a heat pump in which the compressed overhead vapor of the regeneration column heats its own reboiler. A criterion for estimating the energy savings is suggested, based on which a number of efficiency conditions of heat-pump application both in extractive distillation and in distillation in general are formulated. Proceeding from the obtained results, a preliminary discrimination algorithm for versions of the distillation schemes with heat pumps is offered.