淮北煤中12种有害微量元素在煤及其灰中的分布特征

为了解有害微量元素在各煤层中的分布与变化规律,以及在煤燃烧后的煤灰中所发生的迁移与富集情况,采集了淮北煤田不同煤层、不同深度的15个煤样,采用中子活化法对其原煤及灰分中的12 种微量元素(Ag, As,Ba, Co, Cr, Cu, Mn, Mo, Sb, Th, U, V)进行了测试。结果显示:绝大部分有害微量元素的含量都处于n×10 6到n×10 5数量级范围内,不同煤层或同一煤层不同部位中微量元素的含量分布不同;与全国和华北煤中有害微量元素的(平均)含量相比,除Mn低于全国和华北的平均值外,As、Co、Mo、Sb、Th、U与之相近,而Ag、Ba、Cr、Cu、V高于全国和华北煤中的平均值;12种微量元素均在灰分中有所富集,而且富集能力序列为:Cu>Cr>Mn>Mo>Co>Ba>V>Th>As>U>Sb。

CHARACTERISTICS OF THE DISTRIBUTION AND CONCENTRATION OF TWEL VE HARMFUL TRACE ELEMENTS IN COALS FROM HUAIBEI COALFIELD

This study deals with the distribution and concentration of twelve harmful trace elements (Ag, As, Ba, Co, Cr, Cu, Mn, Mo, Sb, Th, U, V) and their enrichment and mobility during coal combustion, in coals and ashes by examining 15 coal samples collected from different coal seams of the Huaibei coalfield using instrumental neutron activation analysis (INAA) techniques. The ranges and mean values of concentrations of these elements were compared, indicating that the concentrations of some trace elements, such as Ba, Cr, Cu and V, are higher in the Huaibei coalfield. In addition, this study deals with the behaviors of these elements during coal combustion in 815℃ electric furnaces and analyzes their concentrations in ashes. The results showed that these elements are more likely to be enriched in ashes of small sizes. The enrichment capacity of these elements follows such a sequence: Cu>Cr>Mn>Mo>Co>Ba>V>Th>As>U>Sb.