Product Details
Air Heaters Tubular for steam generator units High efficiency no
damage to tube
Tubular type Air Preheater
- Air heater and recovery boiler cleaning in power plants is
typically carried out with high-pressure water, chemicals or steam.
- These techniques, while effective on moderate air-side fouling of
heat exchange surfaces, are usually unable to remove the more
tenacious deposits that can build up from fly ash, dust and oil in
coal fired plants.
- Without regular cleaning the heat transfer efficiency reduces,
which in turn lowers boiler efficiency and increases a unit’s heat
rate.
- Severely dirty air preheaters and air heaters can even reduce the
unit’s power output. However, PPL Generation’s Brunner Island plant
has found a highly effective way around these problems by using
pressurized liquid nitrogen.
Function and performance
- Plant air heaters improve boiler efficiency by using exhaust flue
gases to preheat combustion air. This accelerates combustion by
producing more rapid ignition, while also allowing low-grade fuels
to be used1.Each 10 ºC (18 ºF) increase in boiler inlet air
temperature increases boiler efficiency by 1 per cent, up to a
maximum of 10 per cent2.
- Configurations can vary widely, but plants typically use either a
regenerative Ljungstrom-type rotary heater or a fixed recuperative
tubular device. Depending on the configuration, it may also contain
a finned tube air preheater immediately after the forced draft fan.
This keeps the primary heater warmer than the dew point, or acid
saturation point, in the primary air heater baskets or coils. If
this drops below the acid saturation temperature – usually between
87.8 °C and 110 °C, or sometimes at temperatures as high as 126.7
°C – there is a considerable risk of dew point corrosion damage3.
Without preheated air, flue gas products will corrode the heat
transfer surfaces, partially block airflow and, in extreme cases,
limit the power capacity of the unit. While playing a critical role
in increasing boiler efficiency, preheating is only effective if
the air heater is maintained and kept clean of air-side fouling
Advantages
1. Preheated air increases combustion rate and then increases steam
generations of boiler.
2. Due to higher temp. of air,furnace temp.increases,so low grade
coal can be burnt efficiently.
3. Air heated by heat of exhaust gases.It reduces fuel
consumptions.Therefore thermal efficiency of boiler increased.
Details
Layout item | Horizontal layout | Vertical layout |
Tube arrangement | staggered arrangement /in-line arrangement | staggered arrangement / in-line arrangement |
Sealing of pipe and plate | Packing heat- resistant material/
welding | welding |
Anti-wearing | a,when gas scours external tube, welcoming smoke tubes have
protective tile b,when gas scours inside tube,wear casing pipes are installed in
gas inlet |
Product Display
Company Profile
Dehai Boiler is a manufacturer of A-class boiler(Power station
boiler,industrial boiler,HRSG,waste-to-energy boiler,biomass
boiler) and correlated A-class pressure parts intergrating the
design,fabrication,installation,repair and mainteance.

Dehai has ISO9001:2008 certificate issued by France AFAQ-EAQA
Ltd,A-class boiler manufacturing license,ASME S Stamp and U Stamp
authorized certificate.

Through effective management system and high quality products,Dehai
became the qualified supplier of many famous boiler factories and
energy companies and has won a lot of stable customers both
domestic and abroad ,such as :Amec Foster Wheeler,Alstom,Dongfang
Boiler,Harbin Boiler,Hangzhou Boiler,etc.

Based on the business idea of "High quality for survival and
perfect service for development",we shall care for customers'
demand and keep improving our work permanently. To create Dehai
brand,is to serve clients with our improved products and better
performance.

Dehai is located in Economic and Technological Development
Zone,Zhangjiagang City,Jiangsu Province. S38 highway Zhangjiagang
exit is about 1.5 kilometers to the north of our company and the
traffic is very convenient.