准东煤由于其高钠钾特性，在燃烧过程中会引发锅炉结渣等问题，影响锅炉的安全稳定运行。本文以某燃用准东煤的330 MW亚临界四角切圆锅炉为研究对象，采用数值模拟的方法探究不同负荷运行下锅炉的NOx排放以及炉内结渣特性的变化规律。结果表明：负荷降低，炉内切圆直径先增大后减小，25% BMCR炉内气流刚度降低，切圆流动不明显。炉膛温度随负荷降低逐渐下降，25% BMCR主燃区平均温度下降近250 K，投入最下两层燃烧器比中间两层更有利于燃烧稳定。低负荷时炉膛出口处NOx浓度增加，但在屏式过热器和左右墙上炉内结渣强度有效缓解，50% BMCR时一次风喷口的投入方式对四周水冷壁灰渣颗粒沉积量影响较小。

Zhundong coal, due to its high sodium-potassium characteristics, can cause boiler slagging and other problems during the combustion process, which affects the safe and stable operation of the boiler. In this paper, a 330 MW subcritical quadrangular cut-circle boiler burning Zhundong coal is taken as the research object, and numerical simulation is used to investigate the NOx emission of the boiler and the change rule of slagging characteristics of the boiler under different loads. The results show that: the load decreases, the diameter of the cut circle in the furnace increases and then decreases, the rigidity of the airflow in the 25% BMCR furnace decreases, and the cut circle flow is not obvious. Furnace temperature with the load reduction gradually decreased, 25% BMCR main combustion zone average temperature drop of nearly 250 K, into the bottom two layers of the burner is more conducive to combustion stability than the middle two layers. The NOx concentration at the outlet of the furnace chamber increased at low load, but the intensity of slagging in the screen superheater and the left and right walls of the furnace was effectively mitigated, and the input method of the primary air nozzles had less influence on the amount of ash particles deposited on the surrounding water-cooled walls at 50% BMCR.

中国华电集团有限公司科技项目（CHDKJ22-01-35）