DIVERSE PINCH CONCEPT FOR HEAT-EXCHANGE NETWORK SYNTHESIS - THE CASE OF DIFFERENT HEAT-TRANSFER CONDITIONS

In this paper a new concept, the diverse pinch concept, is proposed for total cost targeting and the synthesis of realistic initial heat exchanger networks. It is suggested that the individual film heat transfer coefficients should be taken into account at the earliest possible stage of design when the film coefficients are significantly different. In order to use stream-dependent contributions to minimum approach temperatures the streams are to be vertically shifted by a value proportional to the inverse of the individual film coefficients. The effects of this proposal should be far-reaching. Not only will it make the driving force distribution smoother but it will provide a more realistic initial network supertargeting and avoid some topological traps in the synthesis of initial heat exchanger networks.