(di)still Modeling after All These Years: a View of the State of the Art

Modeling distillation is one of those activities that distinguish chemical engineers from their peers. Modeling distillation is something that chemical engineers have been doing continuously (or in batches) for 113 years. Despite predictions of an earlier demise, distillation modeling is not dead. And, while such forecasts have played a role in the lessening of financial support available for distillation research, it is premature to say that there has been any actual lessening of distillation modeling work. Of course, all the activity is merely a reflection of the immense importance of distillation processes in the chemical process industry, a position that has not weakened over time and which is not likely to diminish in the near future (and perhaps not in the intermediate future either in view of recent trends in the cost of energy). At a time when the chemical engineering profession is expanding rapidly into new fields (many of them with bio and/or nano as part of their names), the author finds it refreshing that conventional (1⁄4old fashioned) distillation still retains a position of singular importance to the CPI, and that distillation modeling remains a topic of interest. This paper takes a look at trends in distillation modeling, highlights the current state of the art, and takes a stab at predicting where models might be going and what will be needed to get there.