Synthesis of safer heat exchanger networks

This paper describes the synthesis of safer Heat Exchanger Networks (HENs) accomplished by performing a risk assessment simultaneously during the synthesis. Considering risks during the synthesis of HENs is important because safety, especially inherent safety, can be successfully enhanced at early stages of design. Because risks depend on the types of heat transfer and equipment selected, a superstructure has been generated for the selection of direct and indirect heat transfer between hot and cold streams and different types of heat exchangers (HEs). Both individual HE and overall HEN risks were analysed and different risk limits have been imposed during the synthesis of HEN, considering toxicity, flammability and explosiveness, accounting for the most important aspects of risk. The results indicate that significantly safer HEN designs exhibiting similar economic efficiency can be obtained.