BY-Cast Products

Cast iron & glass air preheaters

The DEKA airpreheater is a static recuperative heat exchanger principally designed to recover residual heat from combustion exhaust gases by preheating the combustion air supply to burners. This results in an important reduction in combustion fuel requirement.

Cast iron click picture

The heat transfer surface is made by finned cast iron tubes installed in horizontal banks. These cast iron tubes are usually stacked one above another with flue gas flowing vertically downward, outside tubes.

Air flows inside the tubes in cross/counter flow and the tube banks are separated to give a multi-pass arrangement.

In cases where the fuel contains a significant amount of sulfur, the first air pass, i.e. the “cold” end of the airpreheater, can be constructed with borosilicate glass tubes supported and sealed in PTFE tube sheets. This surface is completely resistant to corrosion by acidic condensation. The cold incoming air is heated in this bank before entering the cast iron banks thus protecting the cast iron tubes from condensation and acid attack.

The airpreheater is usually designed to operate with a fired heater, boiler or incinerator.

By-Cast also frequently supplies a DEKA unit for retro-fitting into an existing plant.

The flexible By-Cast design programs and modular construction of the airpreheater will always provide a suitable solution for these retro-fits.