Pinch locations at heat capacity flow-rate disturbances of streams for minimum utility cost heat exchanger networks

The work deals with heat exchanger network (HEN) targeting under heat capac ity flow-rates of streams disturbances. In particular, the aim is to calcul ate all pinches that can exist in a HEN with utilities of minimum cost when stream heat capacity flow-rates (CPs) are allowed to change within given r anges. It is assumed that the disturbances are stochastic. The knowledge of pinches at certain as well uncertain data is of great importance in design ing HENs. For instance, Pinch Technology is based on pinch phenomenon and i ts influence on WEN operation and design. In case of parameter disturbances , this is even more important since additional application in HEN's control (see e.g. [1,2]). It is worthnoting that in case of disturbances, pinches behave in very complex manner as it was shown in [1-5]. A rigorous approach has been developed for calculating all feasible locations of pinches that can occur in minimum utility cost of HENs operating at varying heat capacit y flow-rates of process streams. The method is based on recursive solution of mixed-integer linear programming (MILP) optimisation model that requires quite moderate number of binary variables. Examples of method application and analysis of results are presented in the work. (C) 2000 Elsevier Scienc e Ltd. All rights reserved.