Optimal operation of heat exchanger networks

The paper discusses optimal operation of a general heat exchanger network w ith given structure, heat exchanger areas and stream data including predefi ned disturbances. A formulation of the steady state optimization problem is developed, which is easily adapted to any heat exchanger network. Using th is model periodically for optimization, the operating conditions that minim ize utility cost are found. Setpoints are constant from one optimization to the next, and for implementing the optimal solution special attention is p aid to the selection of controlled variables such that the operation is ins ensitive to uncertainties (unknown disturbances and model errors). This is the idea of self-optimizing control. In addition to heat exchanger networks , the proposed method may also be applied to other processes where the opti mum lies at the intersection of constraints. (C) 1999 Elsevier Science Ltd. All rights reserved.