OPTIMIZATION OF A HEAT EXCHANGER CHAIN CONSISTING OF TWO COLD STREAMS

Abstract
A heat exchanger chain consisting of two cold streams heated simultaneously with the help of any given number of hot streams is considered. The heat exchangers in the chain are optimally sized to yield the minimum cost system. The technique used is the Discrete Maximum Principle. The solution is obtained in the form of two recurrence relations. A heat exchanger system from a petroleum refinery consisting of a total of six heat exchangers is optimized to illustrate the present method.