A simplified scheme of the externally heat-integrated double distillation columns (EHIDDiC), termed SEHIDDiC in this paper, is proposed and studied. Only three external heat exchangers are used to approximate the external heat integration between the rectifying section of the high-pressure distillation column and the stripping section of the low-pressure distillation column. The locations and sizes of the three external heat exchangers are key decision variables and should be considered deliberately to maximize thermodynamic efficiency in process development. A sequential procedure is thus derived for process synthesis and design, and the SEHIDDiC is then evaluated through intensive comparison with conventional distillation columns and the EHIDDiC in terms of the separation of C2 and benzene/toluene binary mixtures. The results obtained indicate that the SEHIDDiC could be an excellent candidate to approximate the EHIDDiC with even a greater reduction in utility consumption and a lesser extent of capital investment. The SEHIDDiC offers essentially a much simple way to design and implement the concept of the EHIDDiC in separation processes.