Heat exchanger network retrofit using individual stream temperature vs enthalpy plot

This paper presents a new graphical approach for Heat Exchanger Network (HEN) retrofit that is based on the individual stream temperature versus enthalpy plot (STEP). STEP maintains the individual stream characteristics and enables users to graphically map hot and cold streams and retrofit HEN without the need to perform enthalpy calculations, or to check for minimum temperature approach violations. Application of the STEP method to a well-established HEN retrofit case study from the literature shows that it only requires one visualisation tool to simultaneously diagnose and retrofit an existing HEN. On top of that, the STEP method yields up to 5 % higher heat recovery as compared to the results obtained using conventional retrofit methods.