NO_x emission characteristics of superfine pulverized anthracite coal in air-staged combustion

摘要

Superfine pulverized coal combustion is a new pulverized coal combustion technology that has better combustion stability, higher combustion efficiency, and comprehensive cost-effective operation. In this paper, the experiment of YQ. anthracite coal combustion was carried out on an electrically heated drop tube furnace. Meanwhile, single air staged and multi air staged combustion were both adopted to understand NO_x emission behaviors and analysis of mechanism and reaction pathways of each experimental phenomenon was proposed as well. The results indicate that the NO_x reduction efficiency of superfine pulverized coal (22.5-32%) in single staged combustion is higher than that of regular particle size (10%). The NO_x abatement in multi air staged combustion is greater than that in single air staged combustion. In multi air staged combustion, the NO_x reduction efficiency of superfine pulverized coal is superior to that of regular size, which may be due to the reaction mechanism where further penetration and adsorption of NO_x takes place in the inner pores. Particle burnout in multi staged combustion ratio was found to be irrelevant to the operating conditions. The findings of this article will provide useful data for the subsequent experiment to investigate into the mechanism of pure NO-char reduction and for the basis of W-flame furnace operation.