Mixing device and burner head for a burner with reduced nox emissions

摘要

To further reduce the NOx emission, the invention provides a mixing device (10) for a burner (16) having reduced NOx production, comprising a centrally arranged first mixing unit (18) for producing a first fuel-air mixture for a primary flame zone (120), wherein the first mixing unit (18) has at least one first fuel nozzle (38) and a baffle plate (40), a second mixing unit (20) for producing a second fuel-air mixture for a secondary flame zone (122), which encloses the primary flame zone (120), wherein the second mixing unit (20) has multiple second fuel nozzles (70), characterized by a sealing air producing unit (24) for producing a sealing air flow in a sealing air zone, which encloses the primary flame zone (120) of the first mixing unit (18) arranged downstream of the baffle plate (40), wherein the second mixing unit (20) is designed to deliver the second fuel-air mixture into the secondary flame zone (122), which encloses the sealing air zone (126), and wherein the second mixing unit (20) is arranged around the sealing air producing unit (24), and by a third mixing unit (22) which is arranged radially between the sealing air producing unit (24) and the second mixing unit (20) and has a swirl generator (76) and at least one third fuel nozzle (74), which is arranged upstream of the swirl generator (76) in a premixing zone (78), through which a swirled air flow flows to the swirl generator (76), to premix fuel from the third fuel nozzle (74) with the swirled air flow before the swirl generation.