电站锅炉燃用高碱煤对燃烧特性影响研究

Research on Combustion Characteristics of High-Alkali Coal in a Power Station Boiler

以某1000 MW超临界塔式电站锅炉为研究对象,采用数值模拟的方法研究了锅炉燃用高碱煤对炉内燃烧特性和结渣特性的影响。使用CFD模拟软件对炉内燃烧过程进行了三维稳态燃烧模拟,并对掺烧不同比例准东煤后的炉内温度场和结焦率等指标进行了比较分析。结果表明,随着高碱煤掺混比例的提高,炉内温度水平逐渐下降,当掺混比例较高时,炉内温度水平已难以匹配正常燃烧的条件。更改煤粉平均粒径的模拟结果表明,粒径和掺混比例都与炉内结渣特性有着较强的关联,这是由不同掺混比例下粒径改变后对于碰壁情况与温度水平的两方面共同作用导致的。

Taking a 1000 MW supercritical tower power station boiler as the research object,a numerical simulation was used to study the effect of burning high-alkali coal on the combustion characteristics and slagging characteristics of the boiler.Using the CFD simulation software,the three-dimensional steady-state combustion simulation in the furnace was carried out after blending with different proportions of Zhundong coal,and the temperature field and slagging rate in the furnace were compared and analyzed.The results showed that with the increase of the high-alkali coal blending ratio,the temperature level in the furnace gradually decreased.When the blending ratio was relatively high,the temperature level in the furnace could not match the normal combustion conditions.The simulation results after changing the particle diameter of pulverized coal show that both the particle diameter and the mixing ratio have a strong correlation with the slagging characteristics in the furnace.