Analysis and performance enhancement of heat pump technology assisted pressure-swing distillation process in the separation of azeotropic mixtures

In this paper, vapor recompressed heat pump assisted pressure-swing distillation process (VRC-PSD) is proposed to explore the ethyl acetate/n-hexane and THF/ethanol/water separating process based on the method explored for defining optimal vapor recompressed heat pump assisted distillation process in our early work. In binary separating process, the VRC-ABR-PSD and VRC-PRE-PSD configurations, respectively, reduce the 52.927% and 52.427% in TAC. And the VRC-ABR-PSD and VRC-PRE-PSD process applied in the separation of THF/ethanol/water ternary azeotrope can reduce TAC by 62.640% and 58.752%.The result demonstrates that all VRC-PSD schemes perform better than the corresponding PSD scheme in terms of economic, energy saving and thermodynamic efficiency. And VRC-PSD scheme with auxiliary bottom reboiler performs better than the VRC-PSD scheme with preheater. Meanwhile, the VRC-PSD assisted with heat integration schemes show better performance than those schemes without heat integration. For the separation of THF/ethanol/water ternary azeotrope, the VRC-ARB-HI-PSD and VRC-PRE-HI-PSD scheme reduce TAC by 67.359% and 63.257%.