煤燃烧过程中5种微量元素的迁移和富集

通过一维炉燃烧模拟实验，研究了褐煤、肥煤、无烟煤及其燃烧产物中As，Cr，Pb，Cd，Hg的含量和分布；计算了在不同燃烧条件下的飞灰和底灰对煤的元素含量比和富集因子，以及飞灰对底灰的元素含量比和富集因子；详细探讨了3种煤在不同燃烧过程中5种元素的迁移和富集行为．结果表明，5种元素在各燃烧产物中都有一定含量的分布，只是各元素在不同燃烧过程中所呈现的集散规律不同，说明煤燃烧过程中微量元素的迁移和富集行为不仅与煤中微量元素的含量和赋存状态有直接关系，还受煤燃烧方式、炉温、气氛条件等人为因素的影响．

THE TRANSFORMATION AND CONCENTRATION OF 5 TRACE ELEMENTS DURING COAL COMBUSTION

This paper studies the content and distribution of 5 trace elements (As,Cr,Pb,Cd,Hg) in the lignite,fatty coal,anthracite and its burnt products produced by combustion simulating experiment in the one dismensional boiler.The trace element contents ratios and concentration factor of coal ashes to raw coals,and the trace element contents ratios and concengration factor of fly ashes to bottom ashes in different combustion condition are calculated.The transformation and concentration of 5 trace elements during different coal combustion are also discussed.The results show that there are some content distribution of 5 trace elements in every burnt product,but the law of concentration and dispersion of every trace element during defferent coal combustion is very different.Experiment results indicated that the transformation and concentration of trace elements during coal combustion are related to the element contents and occurrences of trace elements in raw coal,but are also affected by some man made factors such as the coal combustion,combustion temperature and atmosphere,the type of precipitators and so on.