Controllability analysis of heat integrated distillation systems for a multicomponent stream

Abstract

Understanding the dynamic behavior of distillation columns has received considerable attention due to the fact that distillation is one of the most widely used unit operations in chemical process industries. Heat integrated distillation sequences can provide significant energy savings; however, they exhibit a complex structure which appears to affect their controllability properties. One potential solution to this problem has been suggested through the operation of heat integrated sequences under the conditions that do not provide minimum energy requirements. But, this work proved that the process under the conditions of minimum energy requirements can operate with the best controllability properties. In this work, the controllability properties were analyzed with the application of the Morari resiliency index, condition number and relative gain array, which were frequency-dependent indices. The results showed that the controllability of the best heat integrated distillation column with the minimum total annual cost was better than other sequences.