Patent ID: 6862899

Claim:
A method for heating glass melting furnaces having a combustion chamber, with regenerators for heating primary oxidation gases from the group consisting of air, oxygen-enriched air and oxygen, and port necks which open into said combustion chamber, primary burners, and secondary burners that are installed in a cascade arrangement relative to said primary burners, whereby said primary and secondary burners are operated with fossil fuels, comprising the steps of: operating said primary burners with a larger proportion of said fuel as a primary fuel to produce flame gases under sub-stoichiometric conditions, operating said secondary burners as cascade burners with a relatively low proportion of said fuel as secondary fuel to produce flame gases under over-stoichiometric conditions, mixing together said flame gases produced so that a complete combustion process in said combustion chamber is approximately stoichiometric, supplying said secondary fuel through said secondary burners through one side wall of each port neck to a step, provided in said port neck, said step having a bottom surface and a wall face, introducing said preheated primary oxidation gases to flow from said regenerators over said step into said combustion chamber, blowing a secondary oxidation gas from the group consisting of air, oxygen-enriched air and oxygen into said step during a firing phase of each port neck, in addition to primary oxidation gas preheated in said regenerators that flow over said step.