Heat exchanger

Heat exchanger, as the name indicates is an equipment used to capture the heat of products of combustion and to preheat the air simultaneously. Recuperators and regenerators are commonly used to capture and reuse the heat.

A recuperator is a continuous type of heat exchanger in which both hot and cold streams flow continuously. Both streams are separated by a wall. Transfer of heat from hot stream to cold stream is through the separating wall. Both streams may flow parallel flow as shown in figure (a) or counter -current (as shown in b) or cross flow (as in c). Metallic heat exchangers are used at low temperatures whereas ceramic heat exchangers can be used at high temperatures