Rigorous Design of Fully Thermally Coupled Distillation Column

A rigorous design procedure for a fully thermally coupled distillation column is proposed and applied to an example system of butanol isomer ternary mixture. The design procedure is composed of the calculation of limiting requirements and a rigorous simulation using material and energy balances. The result of the proposed design is compared with the design of a conventional two-column system. It is found that the fully thermally coupled distillation requires less investment and energy cost than conventional distillation, even if higher reboiler temperature is required. It is also pointed out that the dividing wall structure gives less efficient performance than the Petlyuk column having a smaller number of trays of a prefractionator than that of the mid-section of a main column.