The present invention proposes a burner unit (10) for steel making facilities, in particular for use in connection with a regenerative or recuperative heat generator, wherein the burner unit (10) comprises a mixing zone (18); a plurality of fuel feed channels (32) for feeding combustible fuel to the mixing zone (18); and a plurality of air feed channels (34) for feeding combustion air to the mixing zone (18). According to an important aspect of the invention, the burner unit (10) comprises a primary burner (42) with an annular feed arrangement (30) comprising circumferentially alternating fuel feed channels (32) and air feed channels (34); a central channel (44) through the annular feed arrangement (30) and a secondary burner (46) arranged in the central channel (44) of the burner unit (10), the central channel (44) being coaxial with the annular feed arrangement (30).