Experiment and Analysis of Reclaiming the Residual Heat of the Flue Gas of Gas-fired Boiler

The temperature of the flue gas vented by boiler burning gas is higher, commonly reaches 160～240℃. The flue gas contains non-condensation gas and water vapor. The superheated vapor is the main carrier of the heat in flue gas. The paper analyzed the composition of the flue gas and the principle of heat exchange, by the experiment, and proved that the temperature of the flue gas vented by boiler could be lowered and the thermal efficiency of boiler could be increased by the reclaiming of the sensible heat and the hidden heat of the water vapor in flue gas. At the same time, the condensate could absorb part of the acidic gas in flue gas. In this way there is the double effect of saving energy and protecting environment.