Air Preheater

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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 Procurement Of Air Preheater Gear Box
The high- and low-temperature superheaters are installed in the horizontal flue gas pass, the economizer and tubular air preheater are located in the back vertical pass of the boiler.
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.
Energy Services International provides a complete range of pre-commission cleaning needs including steam & air blow equipment, chemical cleaning, oil flush equipment, water flushing, hydrostatic-testing, air preheater cleaning, oil diagnostic services and much more.
Tenders are invited for yearly cleaning of ash from bottom ash hopper, ash pipe trenches, air preheater bottom outlet, cleaning of coal dust from coal carrying pipes at pulveriser points of unit no 1 to 4 at btps
Warranty reliability has been affected by low-temperature corrosion of the tubes of the air preheater (position 3 in Fig.
The company's Turbo Air preheater is available for continuous vulcanization of rubber profiles.
Tenders are invited for Over/Hauling Of Air Preheater Of Blr # 5 & 6.
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.
Tenders are invited for Supply of Fluid Coupling for Air Preheater rotor drive assembly Drawing Enclosed
In connection with local corrosion discovered in low-temperature zones of air preheater (APH) tubes in CFB boilers at Narva Power Plant, the issue of low-temperature corrosion (LTC) became important due to the established nature of the tube damage.