煤及其燃烧产物中砷的分布特征

Distribution of Arsenic in Colal and Its Residues

首先研究了我国各主要聚煤区煤中砷的分布，煤的砷含量均值高于世界但低于美国，低于或接近我国土壤砷含量，但与地壳克拉克值比较，砷在煤中被明显富集。从各聚煤区情况看，砷的含量和富集因子均有中新生代煤最大，华南二叠纪煤为次，而华北石炭———二叠纪煤最小的特点。煤各级燃烧产物中砷分布研究表明，底灰中亏损，但富集于飞灰特别是细粒飞灰的表面，质量平衡率的计算显示砷大多能截留于飞灰中，呈蒸气状态逸散入大气的有限。

The distribution of arsenic in main coal accumulating regions of China have been investigated at first.The average of arsenic in Chinese coals are higher than the world average,but less than American coals;less or close to that in Chinese soil.Arsenic has been obviously enriched in coal on the basis of arsenic clarke.Compared with one another among the different coal bearing areas,concentration and enrichment factor ( EF ) of arsenic is highest for Mesozoic and Cenozoic coals,next for South China Permian coals,lowest for North China Permo Carboniferous coals.Then,study on the distribution of arsenic in coal burnt products has shown that arsenic is dispersed in bottom ash,but enriched in fly ash,particularly on the surface of small fly ash grains.According to the calculation of mass balance rate,arsenic escaping into atmosphere in volatile is little and most can be intercepted in fly ash.