METHOD FOR REDUCING HARMFUL GAS EMISSIONS FROM A GAS-FIRED SEALED COMBUSTION CHAMBER FORCED-DRAUGHT BOILER USING FLUE GAS RECIRCULATION AND ACCORDING BOILER

摘要

A method for reducing harmful gas emissions from a gas- fired boiler (1) comprising a sealed forced-draught combustion chamber (2) in which there is a burner (3) to which there leads a first conduit (5) for drawing in combustion air (A) and from which there departs a second conduit (6) for the discharge of combustion flue gases (F). Provision is made for drawing off a portion of the flue gases or exhaust gases from the second conduit (6) and injecting it into the combustion air (A) so as to reduce the percentage of atmospheric oxygen present in that combustion air (A) and consequently reduce the production of harmful gases in the combustion flue gases (F). A boiler operating according to the aforesaid method is also claimed.