CVP-based optimal control of an industrial depropanizer column

In this contribution we analyze an industrial multi-component depropanizer model and show how to rewrite the original model to index-one formulation t hat is well adapted to dynamic optimization. The optimal control problems a re then studied with the aim of determination of the optimal output traject ories for minimum changeover time requirements and disturbance rejection. T he problems studied are typical situations that frequently occur in the ind ustrial plant. The optimization method used is the control vector parametri zation (CVP) which consists in converting the original problem into a non-l inear programming (NLP) problem which was solved by a successive quadratic programming (SQP) method. The resulting profiles can be utilized as setpoin ts for the existing real plant control. (C) 2000 Elsevier Science Ltd. All rights reserved.