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文中采用Meij提出的相对富集系数 ,分析了煤粉炉中 9种微量元素迁移变化规律。发现大多数微量元素有在飞灰中富集的趋势 ,并且飞灰粒径越小 ,相对富集系数越大。Zn、Cd、Cr在飞灰细微粒子中的富集程度随这些元素的沸点升高而减小 ,由于部分Cr在煤中以有机物形式存在 ,Cr并不遵循底渣中富集程度与沸点成正比。Mn和Cr在底渣和飞灰中含量相当 ,Mn的相对富集系数为 0 8,而Cr的相对富集系数只有 0 4。飞灰中未燃烬的炭以及具有高比表面性质的飞灰对Hg有吸附作用 ,Pb比Cd更容易从煤中挥发 ,而在烟气冷却过程中 ,更趋于在飞灰中沉积。
In this paper, the relative enrichment coefficient proposed by Meij was used to analyze the variation of 9 trace elements in pulverized coal furnace. Most trace elements were found to be enriched in fly ash, and the smaller the fly ash particle size, the greater the relative enrichment factor. The enrichment of Zn, Cd and Cr in fly ash fine particles decreases with the increase of the boiling point of these elements. Because part of Cr exists as organic matter in coal, Cr does not follow the enrichment degree and boiling point of bottom slag Is proportional. The contents of Mn and Cr in the bottom slag and fly ash are equivalent, with the relative enrichment coefficient of Mn being 0 8 and the relative enrichment coefficient of Cr being only 0 4. Unburned ash from fly ash and fly ash with high specific surface properties adsorb Hg. Pb is more easily volatilized from coal than Cd, and tends to deposit in fly ash as the flue gas cools.