水煤浆挥发分再燃对NO还原的影响

Influence of Coal Water Slurry Volatile Reburning on NO Reduction

为了解水煤浆再燃过程中均相还原反应效果的影响因素,在固定床反应器上,利用合成烟气模拟再燃区环境,对不同煤种的水煤浆,在不同的浓度、再燃区温度、氧气浓度、颗粒粒径对挥发分再燃效果的影响进行了研究。实验结果显示:挥发分的再燃效果随着水煤浆浓度的降低而升高,随着煤阶的降低而增加。另外,挥发分含量相同,含氮量高的再燃效果要好一些。再燃区反应温度的升高有益于水煤浆挥发分的释放以及再燃反应。挥发分作为再燃燃料时,再燃区烟气含氧量的影响最大,再燃效果随含氧量的增加而降低。制浆原煤粒径的大小对挥发分再燃的效果有所影响,随粒径的减少再燃效果略有增加。

The homogeneous mechanism of volatile was a major concern when coal water slurry （CWS） was used as rebuming fuel. Influences of volatile rebuming on NOx reduction such as coal rank, coal water slurry concentration, oxygen concentration of flue gas, rebuming zone temperature, particle size, were investigated. Rebuming zone was simulated on a fixed bed reactor with a synthetic flue gas consisting of CO2, O2, NO and Ar. The result show the NO reduction ratio is closely correlated with parent coal rank. For coals contain equivalent volatile matter content, the more high nitrogen content, the more high NO reduction ratio. The content of volatile matter and NO reduction ratio benefit from higher rebuming zone temperature; Oxygen concentration of flue gas has an important effect on NO reduction, with oxygen concentration increasing NO reduction ratio decrease significantly; NO reduction ratio finitely increase when small particle size used.