Air Preheater

Also found in: Wikipedia.

air preheater

[′er ‚prē′hēd·ər]
(mechanical engineering)
A device used in steam boilers to transfer heat from the flue gases to the combustion air before the latter enters the furnace. Also known as air heater; air-heating system.

Air Preheater


a heat exchanger for heating the air passing through it. Air preheaters are widely used in boiler installations of steam power plants and industrial enterprises, in industrial furnace units (metallurgical or petroleum-refining), and in hot-air heating, forced-air ventilation, and air-conditioning systems.

Hot, gaseous products of combustion (in boiler and furnace installations), steam, hot water, or electric power (in heating and ventilating systems) are used as the heat carriers.

Air preheaters are classified as recuperative or feed-water types according to the principle of operation. In recuperative air preheaters the heat exchange between the heat carrier and the air to be heated takes place continuously through the walls of the heating surfaces that separate them; in feed-water air preheaters the heat exchange is accomplished by the alternate heating and cooling of the metallic or ceramic nozzles of the fixed or rotating heating surfaces of the pre-heater. Tubular (steel or cast-iron) recuperative air preheaters, and less frequently rotating feed-water preheaters, are used mainly at thermal electric power plants. Periodic-operation feed-water air preheaters with a ceramic nozzle are widely used in the metallurgical industry. The air can be heated to 450°-600° C with metal units and to 900°-1200° C with ceramic-nozzle units.


References in periodicals archive ?
Tenders are invited for Special assistance for routine maintenance works of boiler auxiliaries like air preheater, electrostatic precipitator, fans, flue gas ducts and pumps for unit-1 or 2 of 2x800mw yeramarus thermal power station for a period of 30 days during the year 2018
Therefore the objective of the given work was to perform laboratory corrosion tests at different temperatures of the metal in order to find out the optimal temperature of tube walls for safe operation of the air preheater.
The hybrid system with solar collectors and an air preheater is analyzed.
Overall, the system is simpler, with only three major components: a fuel preheater, a fuel cell, and an air preheater.
Friable deposits form on surfaces of economizer and air preheater and also in precipitators of different types.
The company's Turbo Air preheater is available for continuous vulcanization of rubber profiles.
Tenders are invited for Special Assistance for Routine Maintenance works of Boiler Auxiliaries like Air preheater, Electrostatic precipitator , Fans , Flue Gas Ducts and Pumps for Unit-1&2 of 2x800MW Yeramarus Thermal Power Station for a period of 60 days during the year 2017-18
Tenders are invited for Work of Complete Overhauling of Boilers With Air preheater of 210MW Boiler s of Unit no-4,5 & 6(Stage II: 3 Boilers) of Wanakbori TPS.
Tenders are invited for Supply of "Triple Screw Pump" and it s Spares for Lube Oil system of Air Preheater of Boiler Unit No.
Tenders are invited for Work of maintenance of air preheater during capital AOH of UNit No.
Tenders are invited for NCTPS II 2x600 MW M I BM Unit II Annual overhaul Renewal and rectification of corroded eroded and damaged expansion joints of Air preheater B pass in primary air inlet