Novel eco-efficient vapor recompression-assisted arrangement for minimum-boiling side-stream pressure-swing distillation system: Preheating feed stream to dew or bubble point

In this paper, a novel eco-efficient intensified vapor recompression-assisted arrangement is developed for side stream pressure-swing distillation (SSPSD) configuration with the ethyl-acetate and ethanol separation as the illustrative example. The special characteristics for this novel system are that the feed streams are preheating to their dew points through condensing some portion flow of energy-elevated overhead vapor stream from highpressure column and another is used to boilup the bottoms in reboiler. The economically optimal process is the novel vapor recompression-assisted SSPSD arrangement (NVRC1-SSPSD-HEN) with heat exchanger network (designed by the Aspen Energy Analyzer based on the pinch technology) wherein only the high-pressure column takes this novel option. Compared to the optimal self-heat recuperative arrangement of preheating feed streams to their bubble points (VRC-SSPSD4-HEN), it can achieve the reductions of 18.81% (77.83%) in energy consumption rates, 27.97% (91.69%) in CO2 emissions, and 3.75% (27.80%) in total annual cost (TAC) as well as an enhancement of 23.61% (336.93%) in thermodynamic efficiency. The data in brackets refer to the basic SSPSD case. The main advantage of this novel process is concentrated on reducing energy consumption, especially of electricity consumption, and the 15.72% less in compressor power is achieved in this novel proposed system.

Automated summary

A novel eco-efficient intensified vapor recompression-assisted arrangement has been developed for side stream pressure-swing distillation, with ethyl acetate and ethanol separation as an example. The new configuration shows significant improvements in energy consumption, CO2 emissions, cost, and thermodynamic efficiency compared to traditional self-heat recuperative arrangements.