During combustion of natural gas, water in the combustion air changes phase from liquid to gas. As a result, combustion products of natural gas typically contain 11% to 12% moisture, which represents up to 9% of beginning fuel content. With typical economizers, this energy escapes into the atmosphere with heated boiler gases. But a condensing economizer allows its recapture.
Using feedwater-cooled finned tubing, a condensing economizer cools exhaust gases below their dew point, releasing latent heat bound up in the vapor. The amount of recaptured heat is considerable — about 1,000 Btu per pound of condensate. The CO2 reduction is also significant: one cubic foot for each cubic foot of natural gas saved.
E-Tech condensing economizers yield extremely high efficiencies — upward of 96%. Their vapor-condensing environment presents an ideal heat recovery solution for industries that use non-sulfur bearing fuels, whose acidic by-products can corrode most carbon and alloy materials.