A NOVEL VISUALIZATION TOOL FOR HEAT-EXCHANGER NETWORK RETROFIT

Research into heat exchanger network (HEN) retrofit has focused on eit her complete automation or evolutionary, thermodynamic approaches. The former involves the solution of mixed-integer, nonlinear programs, wi th the advantage of rigor, but suffering from exorbitant computational overheads. On the other hand, existing thermodynamic approaches, thou gh useful in greenfield design, are inadequate for retrofit problems. Using a visualization tool that makes graphically explicit both the lo ads and the driving forces in a heat exchanger network-providing a suc cinct, graphical description of the first and second laws of thermodyn amics applied to the system - we present design guidelines which facil itate rapid evolution of good retrofit solutions by inspection. The me thod is elucidated using case studies, the retrofits proposed are comp arable or superior to existing solutions and are more rapidly obtained , and the rationale behind the proposed modifications is easily docume nted. This final feature greatly enhances the industrial acceptability of the approach.