100 MW锅炉NaOH颗粒生成的数值模拟

煤粉燃烧过程中矿物质的气化、成核、凝结等过程是炉膛中亚微米颗粒形成的主要途径。本文运用CFD软件针对某100 MW锅炉内NaOH颗粒形成进行了数值研究，计算得到了炉内的温度分布、氧浓度分布和亚微米颗粒数量浓度和质量浓度分布。结果显示，亚微米颗粒的生成数量与温度具有强烈的相关性，温度较高的区域亚微米颗粒数量浓度较大，温度较低的区域则较小；而在炉膛的高温区内，NaOH颗粒的质量浓度并不是最高，而是最低，同时随着炉膛高度的增加，NaOH颗粒的质量浓度逐渐增加。计算结果为今后数值研究燃煤过程中亚微米颗粒的形成与演化奠定基础，为研究温度等燃烧条件对亚微米颗粒形成的影响、抑制其排放等方面提供了一种有效研究手段。

Numerical simulation of NaOH particle formation in a 100 MW utility boiler

In coal combustion process, the submicron particles are produced by vaporization of mineral matter and their subsequent recondensation, then growing-up by coalescent collisions and heterogeneous condensation. This paper presents a numerical simulation of the NaOH particle formation in a 100 MW boiler by CFD software. The distributions of temperature, oxygen concentration, number and mass concentration of the submicron particles are obtained by the calculation. The results show that the number concentration of the submicron particulate matter have intense correlativity with the furnace tenmperature, the number concentration of the submicron particulate matter is higher in the high temperature zone, it is lower in the low temperature zone. Simultaneously, the mass concentration is not the highest in the high temperature zone, but the lowest. With the increase of the furnace height, the mass concentration of NaOH particle increases gradually. The calculation results provide the effective methods for studying the submicron particulate matter formation, influencing factor and control during coal combustion.