Targeting minimum number of heat-exchanger units with Mathematical Programming

17 outubro 2024, 16:00 • Pedro Castro

Mixed-Integer Linear Programming model for finding the minimum number of units given the heat loads to be supplied by hot streams and utilities to cold streams and utilities in each temperature interval (expanded transshipment model by Papoulias & Grossmann, 1983). Hands-on session in GAMS for: (i) writing the missing objective function and model constraints, which involve heat balances for each hot and cold stream/utility in each interval, and the activation of binary variables identifying a match between a pair of hot and cold stream/utility in case there is an heat load exchanged between the two; (ii) generating the corresponding heat-exchanger network (HEN) for the regions above and below the pinch. The HEN for the full network is much more difficult to derive (it involves stream mixing and splitting) given the heat loads between every pair of streams, requiring a systematic procedure.