Rapid Screening of Conceptual Design Alternatives for Distillation Processes

Abstract:
The selection of the optimal separation scheme in a chemical process is a complex and demanding task due to the large amount of topologically different designs and internal degrees of freedom which must be considered. This dissertation presents a new optimization-based framework for rapid economic screening of design alternatives for distillation processes. The new approach is based on the determination of the minimum energy demand of each column by a shortcut design method for nonideal azeotropic mixtures. Feasibility and operability of the design are enforced using a feasibility check based on bifurcation analysis. These two elements are used to formulate the design problem in form of a compact nonlinear optimization problem which can easily be solved using standard algorithms. The new framework and its implementation in a ready-to-use software tool help to identify design opportunities and raise economic potential. The application of the framework is highlighted with several illustrative examples as well as a detailed case study on alcohol purification.