Air Preheaters


SPX Heat Transfer provides engineering, manufacturing, and field services to evaluate and modernize Air and Gas Preheaters, including Rothemühle regenerative heat exchangers and other rotor and stator type air preheaters. New, improved components, including custom designed sealing systems and heating elements, are incorporated into the preheater upgrades, offering lower leakage and less wear, better heat efficiency and less pressure drop, and providing excellent resistance to corrosion, erosion, plugging, and temperature shock.

Advantages of upgrades and modernization to minimize leakage and air-to-flue gas flow include plant megawatt savings and significant fan amperage reduction. The resulting ability to recover previously lost energy output and provide additional power to the grid allows payback of the capital investment in a matter of months.

Component Inspection*

  • Sealing system collar seals
  • Levelness of stators/rotors
  • Position of shaft
  • Condition of sealing system, sector plates, sleeves
  • Condition of heating surface
  • Cold, intermediate, hot layer
  • Adjustment of sealing system
  • Efficiency of cleaning system
  • Collection of operating values

*Recommended interval is 8-12 months prior to next planned outage.

Modernization Services

  • Design calculations
  • Layout design
  • Design engineering
  • Project management
  • Manufacturing supervision
  • Quality management
  • Manufacturing of key components
  • Shipment logistics
  • Site supervision
  • Commissioning
  • Performance testing
  • After-sale scheduled inspections and maintenance

Primary Benefits

  • Less pressure drop by modernizing the heating element profiles
  • Higher heat efficiency as a result of new baskets, profiles, and heating element designs
  • Lower leakage and less wear with advanced design sealing systems
  • Cleaner heating elements by providing modern soot blowing systems

Added Benefits

  • Increased precipitator efficiency by lowering flue gas velocity and mass flow
  • Decreased power consumption of related induced fans, gaining back lost MWs

Available Component Upgrades

  • Newly redesigned seal frames with asymmetrical seal shoes help minimize unwanted pulsations and wear
  • New open design collar seals with minimum number of tangential acting tension springs (maximum of four spring positions)
  • New collar seal designs provide less leakage, longer service life, reduced maintenance cost, easy inspection, and service
  • Sensor controlled automatic seal setting systems reduce leakage in all load cases with no wear
  • Increased heat efficiency by using a wide range of various heating element profiles with different materials
  • Use of enameled heating elements for SCR (selective catalytic reduction) and FGD (flue gas desulphurisation) applications to prevent against acid attack from clogging and ensuring easy cleaning

Heating Element Details

  • Custom designed
  • Low plugging tendency and low pressure resistance
  • High heat transfer rate
  • Easy to clean surface
  • Resistant to corrosion and erosion
  • Patented enameling process for long life under severe industrial conditions – ideal for SCR operation
  • Temperature, shock resistant
  • Basket arrangement for fast and easy replacement
  • Adjustable plate thickness to withstand flue gas erosion

Contact SPX Heat Transfer today to speak with one of our knowledgeable professionals about Rothemühle Air Preheater solutions!

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Headquarters: 918.234.6000