ENERGY INTEGRATION OF INDUSTRIAL-PROCESSES BASED ON THE PINCH ANALYSIS METHOD EXTENDED TO INCLUDE EXERGY FACTORS

The energy integration of industrial processes is becoming increasingl y more effective thanks to new methodological developments such as pin ch technology. This paper aims at extending the number of factors cons idered in pinch analysis towards a life-cycle optimisation and propose s new synthesis representation schemes. The original pinch method cent res primarily on maximizing the internal heat transfer with the choice of appropriate Delta T(min)s. The proposed extension takes into accou nt the complete heat transfer exergy losses, the pressure drop exergy losses and the exergy associated with the fabrication of the heat exch angers. The extended composite curves graphically represent the above- mentioned losses on a Carnot factor versus heat rate diagram. In a sim ilar way, other high exergy inputs and outputs linked, for example, to the introduction of heat pumps and cogeneration units, are represente d on a topping electricity versus Carnot factor diagram. Such an exten ded exergy synthesis results in an improved and more coherent exergy b alance for comparing energy recovery schemes. It offers a new insight and permits the identification of solutions which are more stable in t ime and fairly independent of changing economic conditions. The propos ed approach is suitable for future extension to include pollution and resource scarcity factors. Copyright (C) 1996 Elsevier Science Ltd.