Simulation of separation of monoethanolamine and triethylenediamine by common and double effect pressure swing distillation

Pressure swing distillation for separating monoethanoiamine and triethylenediamine was proposed based on the feature that the azeotropic composition of the system was influenced by pressure difference in the system, and double effect pressure swing distillation which was double effect distillation coupled with pressure swing distillation was proposed to save energy of the system. Process simulation for the pressure swing distillation and double effect pressure swing distillation was carried out by using the Aspen Plus software. The results showed that monoethanoiamine and triethylenediamine with high-purity(the both could reach 99.90%) could be obtained by the two separation methods, but the double effect pressure swing distillation could save energy by 29.65% in heating process and by 31.51% in cooling process compared with the pressure swing distillation.