The relation between availability loss and thermodynamic irreversibility in distillation has been analysed theoretically. Various practical methods in reducing the thermodynamic irreversibility and cutting down the avaibility loss have been proposed and studied. Real instances prove that running cost and energy consumption can be cut down to a large degree by retrieving as much energy as possible during the ditillatwn process, by raising the thermodynamie efficiency of the distillation system and by reducing the...