An air preheater is a device that transfers heat energy from the exhaust gases to the incoming air. This equipment is used in boiler installations, as well as in various industries to create optimal conditions for technological processes. The supply of heated air to the combustion chamber contributes to an increase in the combustion temperature and makes the combustion process more intense; as a result, the efficiency of the boiler or metallurgical furnace increases.
Types of air preheaters
According to the principle of operation air preheaters are divided into recuperators and regenerators. In recuperators, heat transfer occurs continuously, heat transfer is carried out through a hermetically separating medium element. In regenerators, the heat transfer surface alternately contacts with the heating and heated medium, which does not exclude partial mixing of the medium.
According to the design of air heaters, recuperators are divided into several types with tube units as the most commonly used type. The heating medium in this unit moves inside the pipes, and the air is heated when passing between them.
More efficient air preheaters are the heat exchangers of the new generation of OPT. The OPT recuperators consist of steel panels, which serve as heat transfer channels separators for the passage of medium. The circuit for switching on the OPT air heater can be direct-flow, counter-current or cross-flow.
Features of air preheaters
A comparative analysis of the characteristics of air preheaters in conventional design and brand new units of the OPT shows that with the same equipment dimensions, the efficiency of the panel air preheater OPT is several times higher. In addition, the performance of OPT units can be further increased by increasing the area of the heat transfer surface and reducing the cross-section of the channels without changing these dimensions. This gives OPT recuperators an advantage and makes them attractive for use in production and industry.