SUPERCHARGED HEAT-EXCHANGER NETWORKS

An expander coupled directly to a compressor, that is, a 'supercharger', can be used in an evaporative process to enhance the performance of a heat exchanger network and, under appropriate circumstances, the operations that are embedded within the network. Substantial reductions in the utility steam requirements are possible in principle. A simple stand-alone binary distillation process is used to demonstrate the concept and its possibilities. Computer simulation of one supercharged network configuration predicts a utility steam consumption which is over 35% less than that of the best unsupercharged design. Both an open circuit (Rankine) heat engine and an open circuit liquid decompression heat pump are embedded within the supercharged distillation process. The effect of the supercharger is, primarily, to make it possible for the heat exchangers in the network to recover a much greater proportion of the heat that is available than would otherwise be feasible.