ABSTRACT
The efficient use of heat from a variety of low-grade heat sources described in Chapter 2 requires their efficient integration into the heat supply, distribution and usage system including all other existing energy sources and heat consumers. Such system can include the number of streams to be heated and streams that have heat energy that can be extracted as they are cooled. These streams can exchange heat energy with the use of heat exchangers that as a system of devices transforming heat energy of hotter streams into the heat energy of cooler streams represent a heat exchanger network (HEN). With the same system of streams, the structure of HEN and heat transfer areas of constituting it heat exchangers can vary to a great extent with the significant differences in total heat energy exchanged (recuperated), as well as heat exchangers numbers, heat transfer areas and costs. The design of HEN represents the problem of finding the structure and parameters constituting heat exchangers that correspond to a certain optimum objective function. The widely adopted approaches for HEN design can be divided into two groups, namely, mathematical programming and Pinch Analysis as a basic methodology of Process Integration.
