Systematic design of the integrating heat pump into heat integrated distillation column for recovering energy

Abstract

Many developed energy efficient configurations based on heat-integrated distillation column (HIDiC) have been proved to be attractive separation alternatives for saving energy. The key limitation of heat integrated technology is how to build splendid schemes for the heat integrated distillation column. In this work, the overall economic evaluation of conventional distillation column (CDiC), basic heat-integrated distillation column (basic HIDiC) and vapor recompression column (VRC) were executed systematically. Based on the comparison of results, by coupling the basic HIDiC with heat pump technology, a new distillation process model was developed as an intensified HIDiC (int-HIDiC) configuration for propylene-propane splitter. By this enhanced heat integration, the reboiler and the low pressure steam were no longer needed in the process. Meanwhile, the heat distribution proportion and the corresponding operating conditions of this int-HIDiC were optimized through vast simulations and computations. Finally, based on the above optimization results, we developed a simplified HIDiC configuration with two separated columns. The results show the better economic and energy performances than all the other energy-saving schemes including VRC.