Impact of radial air staging on gas-particle flow characteristics in an industrial pulverized coal boiler.

Radial air staging is a new air staging method for industrial pulverized coal boilers. In this paper, its impact on the gas-particle flow characteristics of industrial pulverized coal boilers was studied experimentally. The gas-particle flow experiments were carried out on a 1:6 scale boiler platform by a particle dynamics anemometer. The three-dimensional velocities of the gas-particle, average particle size and particle volume flux under different air stoichiometries in the furnace were measured. When the air stoichiometry was 0.2, the burner outlet could not form a stable reflux zone to establish a good combustion process. When the air stoichiometry is greater than 0.8, the maximum particle volume flow is also located near the water wall, increasing the slagging tendency on the wall. The appropriate air stoichiometry range for the new burner was 0.4–0.8. [Display omitted] • Radial air staging was a new air staging method. • Laboratory test and industrial application on the radial air staging were performed. • The appropriate range of air stoichiometry is recommended to be 0.4–0.8. • Anti-slagging and low NO x combustion are realized on industrial boilers. [ABSTRACT FROM AUTHOR]