Airpreheater – Introduction, Working, Types, Applications

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Airpreheater Introduction, Working, Types,
Applications
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Airpreheater

• Introduction
•  Introduction
• What is Airpreheater
• Working of Airpreheater
• Types of Airpreheater
• Advantages
• Applications

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Airpreheater

• Airpreheater Diagram-

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What is Airpreheater

• A very basic word to word meaning is a device
  used to heat the air before processing it to
  further use.
• They are also recognized as air heaters or
  air-heating pipe.
• It is designed to work to exchange heat energy
  with desuperheaters.
• Desuperheater is a Device which is been used to
  reduce the temperature of the steam in a high
  heat generation plants where large amount of heat
  energy or steam is released in the atmosphere

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Working

• Airpreheater can be performed by fashion counter
  flow, co-current flow, co-current
  flow-countercurrent or cross-countercurrent or
  cross-co-current flow.
• The design of the device is depend on the media
  and the temperature conditions of the application
• Is in the exhaust gas or in the air containing
  dust or other particles, so that deposits are
  expected, preferably smooth tubes are used, which
  are less prone to deposits and will be clean
  easier.
• As they are heating the air passing through it by
  means of wasted heat energy airpreheateras are
  used in various areas such as boilers, industrial
  furnace units and in hot-air ventilation systems

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Types of Airpreheater

• Types of Airpreheater
• According to the working principle
  airpreheaters are divided into two types
• Recuperative or tubular type
• Regenerative or feed water type

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Recuperative or Tubular Type

• Recuperative type of airpreheaters is preferably
  used in small and medium size boilers.
• In this type heat energy exchange is carried out
  through the walls of heating surface that
  separate the heat energy carrier and air to be
  heated.

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Regenerative or Feed Water Type

• In this type a feed water airpreheaters exchange
  of heat energy takes place through alternate
  heating and cooling of metallic or ceramic
  nozzles of the fixed or rotating heating
  surfaces.
• Regenerative air preheaters are compact and can
  have stationary rotating hood.

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Advantages of Airpreheater

• It increases thermal efficiency of the system
• Payback period is very short and increase
  combustion rate
• Improve and strengthen the combustion
• Reduces the loss of furnace and the exhaust gas
  temperature, improve the boiler thermal
  efficiency.
• Airpreheater is suitable for all standard fuels
• They are easy for retrofit into existing systems

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Applications

• In refrigeration economizer system
• Ovens used in home appliances and industrial uses
• The dryer applications are heavy energy consumers
  in the food and non-food industry. Hot exhaust
  stream is transferred to the cold air inlet
  stream by using the Airpreheater.
• In the applications where indirect fired air
  heaters are required.