Integration of heat pumps in industrial processes

Artikel i vetenskaplig tidskrift, 1994

In spite of several technical and economic advantages, the number of heat pumps in industry is still very low compared to those for house heating. There are several reasons for this; one of the important ones being a lack of knowledge of how to find good, economic applications with the aid of process-integration principles. With the aid of these principles, the appropriate design in terms of heat pump type, size and heat source and sink temperatures can be identified. In doing that, the characteristics of both the industrial process and the heat pump must be taken into account. For the process the pinch temperature, the shape of the composite curves and the number of heat exchangers in the system are the most important factors. For the heat pump, the possible COPs that can be achieved and the ratio of heat to heat sink/heat from heat source are the most important factors, in addition to investment costs, energy prices etc. Methods for optimization of the main parameters in a grassroot design and for finding the most appropriate designs in a retrofit situation have been developed. With the aid of such methods, the potential for heat pumping in industry can be shown to be higher than earlier anticipated. Studies in real plants have verified this.