Process and burner for reducing NO¶x¶ formation from coal dust combustion

摘要

The burner involves connecting a primary dust pipe (6) to a dust pipe (7) and conveying a mixed flow of primary air and coal dust. The primary dust pipe is enclosed by a secondary and tertiary air pipes (10,11), both of which continue into a conically widening section. The pipes have a swirling appliance (22,23) and are connected to a spiral inlet housing (16,17). The outlet end of the primary dust pipe has a stabiliser ring (8), the primary dust pipe is enclosed by a primary gas pipe (9) forming a ring channel. A dust-free part-flow of the mixed current flows through the primary gas pipe. A part-flow rich in dust flows through the primary dust pipe. The dust pipe contains a swirl piece (24) downstream from which is an immersion pipe (25) connected to the primary gas pipe by an outward leading pipe (26) via a spiral inlet housing.