中国煤中汞的含量、分布与赋存状态研究

The Abundance,Distribution,and Modes of Occurrence of Hg in Chinese Coals

在测试分析中国皖北矿区6个煤矿81个煤样品中汞含量的基础上,结合国内外文献资料中报道的1 712个中国煤样品中汞的数据,对中国煤中汞的含量、分布、赋存状态及燃煤引起的汞的环境污染进行了分析和探讨。通过研究得出:中国煤中汞的平均含量为0.20 mg/kg,高于世界煤中汞的平均值(0.10 mg/kg),接近美国煤中汞的平均值(0.17 mg/kg);由于沉积环境及成煤过程中各种地质因素的综合影响,汞在中国不同地区、不同成煤时代以及不同变质程度煤中的含量差异较大;高硫煤中的汞与硫化物关系密切,主要赋存在黄铁矿中;硫化物结合态和有机结合态是低硫煤中汞的主要存在形态;岩浆活动对煤中汞的含量分布与赋存状态有明显影响;煤中汞的赋存状态与煤中汞的释放、毒性有着重要的关系,中国巨大的煤炭消耗量,已引起大量的汞排放,控制燃煤过程中汞的排放是今后环境保护的重要内容之一。

81 coal samples were collected from six coal mines in Wanbei Coal Mining District,China. The contents of Hg from 1 793 coal samples were analyzed,and the concentration,distribution,mode of occurrences of Hg in Chinese coals and the impact of Hg emission on the environment were studied. The environmental impacts and typical features of Hg were also discussed. It is concluded that the average Hg values in Chinese coals is 0. 20 mg / kg,which is higher than the average value of the world coals（ 0. 10 mg / kg） and close to that in the U. S. coals（ 0. 17 mg / kg）. The contents of Hg vary in different coal basins,geological ages,and coals ranks. Most likely modes of occurrences of Hg in high-sulfur and high-Hg coals are in solid solution in pyrite. But in low-sulfur coals,the modes of occurrences of Hg are more variable,and organic-bound and sulfide-bound Hg may dominate. Magmatic activity may influence the concentrations and modes of occurrence of Hg in coals. Hg emissions during coal combustion have resulted in serious environmental contamination in China,and it is significant to control the emissions of Hg during coal combustion.