Recovery of waste heat from the exhaust gases to heat the feedwater, conserving energy and improving boiler efficiency up to 95%. 

Fuel costs can typically be reduced by between 5%. The typical temperature of flue gases flowing from the final pass of tubes from a 3-pass wetback 150 psi steam boiler would be 240 degrees C. This heat is then lost up the chimney to the atmosphere but some of it could be recovered utilizing a flue gas economizer and used to pre-heat the boiler feed water.

Hotter feed water requires less fuel input to raise steam, therefore saving fuel costs and reducing carbon emissions. An economizer is a pressurized heat exchanger with heat indirectly transferring between hot flue gas flowing around banks of tubes through which the feed water passes. The tubes are designed with spiraled surfaces to achieve maximum surface area and enhanced heat transfer. Economizers are available as an optional feature of the AlkaBoiler® RF & FWB Series or as a stand-alone unit which can be retrofitted to an existing boiler on site. Our Service team are available to help ascertain the most energy efficient solution for your particular application.