Pinch Analysis first emerged as an energy-saving approach to the design of heat exchanger networks which concentrated on conceptual understanding. It did not seek automatic global optimisation, but instead user-driven solutions which were near-optimum for practical problems.

It has developed with speed from an energy-saving tool for heat exchanger networks into a general tool for overall process design. It is now being used for process changes, capital cost reduction, emissions reduction, debottlenecking, batch process design and total site integration.

The early developments relating to heat exchanger networks are still those for which it is widely known, rather than the much more significant and wide-ranging later developments relating to overall processes. Here we shall introduce the key principles and steps of Pinch Analysis, both well-established and more recent. However, even though Pinch Analysis can be used as a wide-ranging tool covering many aspects of process design, consideration will be restricted here to energy saving in heat exchanger networks.

A. Track Record

Pinch Analysis, has developed an impressive track record. The firstly publicly reported applications from ICI averaged 30% energy savings in chemical and petrochemical processes Linnhoff and Turner (1981). Similar applications reported by Union Carbide a few year later showed energy savings averaging 50%, resulting mainly from a better understanding of how to carry out process changes Linnhoff and Vredeveld (1984).