Pulverized coal burner

摘要

The pulverized coal burner suitable for lowering the concentration of nitrogen comprises a pulverized coal nozzle (10) for jetting a mixture of pulverized coal and primary air, a secondary air nozzle (11) and a tertiary air nozzle (12), concentrically arranged around the outer periphery of the pulverized coal nozzle (10), and a tube expanded portion (20) at the end of a partition wall separating two adjacent air nozzles. A flow shift means for shifting the secondary air in the secondary air nozzle so as to flow along the tube expanded portion, for example a guide plate (61), is provided. The secondary air comes to be jetted outward by the guide plate, and mixing of the secondary air and the tertiary air with pulverized coals is delayed, whereby an amount of occurrence of NOx can be decreased. The guide plate (61) is a ring disposed in an outlet region of the secondary air nozzle (11), which ring has a taper-shaped ring portion for guiding a part of the secondary air (52) in a radially outward direction.