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研究碱金属与碳烟的相互作用对于深入了解煤燃烧初期的细颗粒物生成与演化机制是非常重要的.本文采用Hencken燃烧器与ELPI+分级采样系统,对准东煤和其酸洗煤在不同气氛下30 ms停留时间处所取样的细颗粒物进行测试分析.研究发现准东煤产生的碳烟存在明显的Na元素掺杂,在20％ O2条件下几乎完全氧化并被矿物质颗粒物替代.酸洗之后准东煤碳烟产量增加40％,并且碳烟的氧化速度明显降低,导致在20％ O2条件下碳烟大量存在于细颗粒物中.使用HRTEM研究了掺杂Na的碳烟的微观结构,结果表明在挥发分的二次反应中碱金属与高分子烃存在多种相互作用机制.“,”Study on the interaction between soot and alkali metals is critical for deep insight into particle formation and evolution mechanisms in the initial stage of pulverized coal combustion.In this work,fine particles derived by ZD and its acid-washed samples at different atmospheres were analyzed using Hencken burner and ELPI+.It was found that Na doping was significant for the soot derived by ZD coal,which was almost oxidized and replaced by mineral particles at 20％ O2 condition.After acid wash,soot yield was increased by 40％ and the oxidation rate was lowered,resulting in the enrichment of soot in fine particles at 20％ O2 condition.Microstructures of Na-doped soot was examined by HRTEM and the result suggested the multiple interaction mechanisms between alkali metals and heavy hydrocarbon during secondary reaction of volatile.