DEVELOPMENT OF AN HYBRID CATALYTIC GAS BURNER FOR CONDENSING BOILERS

A novel hybrid catalytic radiant gas burner suitable for EU condensing boilers (4 - 25 kW) based on the concept of rich-catalytic homogeneous combustion with interstage heat removal was developed. Operation of the hybrid burner was completely characterised with special focus on the catalytic stage which also acts as radiant element. Methane combustion tests were conducted in direct comparison with two low-NOx forced air commercial systems: a fully premixed gas burner stabilized with a knitted metal wire cover, and a blue-flame turbulent diffusive burner with multiple swirled fuel nozzles and high speed air injection. The novel burner shows improved performance with regards to efficiency, emissions, stability, and safety of operation.