The energy integrated distillation train is synthesized in two levels: Maximizing the net benefits of heat inte-gration over both design variables of the simple columns and heat-matches among them

and then minimizing the total costs of the train over all separation sequences by means of integration trees. It does not involve much computation because the feasible heat matches are few and a simplified technique to determine the optimal distillation pressure is employed. The synthesis procedure is illustrated by a popular example

and the comparison of the synthesis results of different methods shows that the new strategy can achieve more savings in both energy and separation costs.