中文摘要：

对典型西部低阶煤进行逐级提取、热解／燃烧实验及热力学计算，研究煤中重金属Cr的赋存形态、燃烧排放特性及金属氧化物对铬迁移转化的影响。结果表明，BCR逐级提取法相比常用的水铵酸逐级提取法对研究低阶煤中Cr赋存形态有很大优势，四种西部低阶煤中Cr主要以有机态和残渣态形式存在，其中万向煤中有机Cr含量高达65．36％。与N2相比，C02对煤中Cr的分解释放有一定的抑制作用，燃烧过程中O2的加入对Cr的释放影响不大，燃烧温度对煤中Cr释放的影响与煤种有关。CaO和MgO对剧毒Cr（VI）的生成有一定的促进作用，而Fe基矿物对捕获Cr蒸汽同时抑制燃煤六价铬的生成有很大优势。

英文摘要：

The speciation of Cr in typical western low-rank coals and release characteristics were investigated through sequential extraction and pyrolysis/combustion experiments. The results show that compared with water-ammonium acetate-acid sequential extraction method, BCR extraction method has advantage in studying the speciation of Cr in low-rank coal. Chromium mainly exists as organic forms and residue state in the studied four coals, especially Wanxiang coal, the organic-Cr is up to 65.36%. The high concentration of CO2 inhibits Cr vaporization. Compared to pyrolysis, O2 has little affect on Cr release during coal combustion. The influence of temperature increase on Cr release depends on coal variety. CaO and MgO promote the formation of Cr（VI）, however, Fe203 inhibits Cr（VI） production during coal combustion.