Flame burner dome flat with low emissions

Burner dome flat flame (10) adapted to be installed in a vault (21), which delimits the combustion chamber (20) of a heat treatment furnace steel, the burner (10) comprising a cylindrical metal body hollow main (12), an individual duct (13) for conveying gas concentric to the main body fuel (12), a central inner nozzle (14) for injecting a fuel gas, and a conduit conveying the individual air (30) connected to the body cylindrical hollow main metal (12), characterized by comprising: - at least two outer nozzles (17) outside of said main body (12) to inject fuel inside the combustion chamber (20), - a first device dividing (15) as a valve for regulating the flow division of gas fuel core; - a distribution system gas (16) consisting of a series of pipes (16 '), designed to feed said at least two outer nozzles (17), - a second splitting device (18) indicated as a second valve division to regulate the flow of gas in said at least two outer nozzles (17).