Computer-aided heat exchanger network design

Abstract

The objective of this thesis is to develop for heat exchanger networks (HENs) synthesis, based on a combination of the pinch design method and heuristic rules. The software is developed under the following assumptions. 1. Process conditions are known and unchanged. 2. No change of phase of any fluid stream occurs during heat exchange. 3. Heat loss from exchangers to environment is negligible. The obtained maximum-energy-recovery (MER) HEN is further improved by applying an evolutionary procedure to minimize the number of units, in which the program will automatically search for and break up primary loop up to the second-level. Through actual applications of the software to various published examples, it has been shown that the MER networks obtained satisfy the minimum utility requirements while the HENs obtained by loop breaking successfully minimize the number of exchanger units in a majority of the examples studied. The thesis describes the general algorithm and features of the software and show some typical examples studied.