沈北煤田煤中伴生元素分布特征

Distribution of Associated Elements in Coals from Shenbei Coalfield

对采自辽宁沈北煤田的７个刻槽煤样，应用电感耦合等离子体原子发射光谱（ＩＣＰ－ＡＥＳ）与仪器中子活化分析（ＩＮＡＡ）测定煤中８个氧化物与２０个微量元素的含量．与中国煤、美国煤、世界煤中元素质量分数对比表明：沈北煤田煤中大部分元素质量分数处于正常水平，而Ｎａ，Ｃｏ，Ｃｒ，Ｃｕ，Ｎｉ与Ｓｃ的质量分数偏高，且Ａｓ，Ｃｏ，Ｃｕ与Ｎｉ在煤中明显富集，分析认为煤中Ｃｒ和Ｎｉ质量分数较高且富集的主要原因与煤系基底橄榄玄武岩有关．相关与聚类分析以及扫描电镜能谱（ＳＥＭ－ＥＤＸ）分析显示：Ｃｏ，Ｍｏ和Ｓｎ与粘土矿物有关；Ｂｅ，Ｂｒ，Ｐ，Ｍｎ与Ｖ显示出有机亲和性；Ａｓ，Ｐｂ，Ｔｈ，Ｕ和Ｚｎ与硫化物矿物有关；Ｃｒ，Ｃｕ与Ｎｉ可能与硫化物矿物有关；Ｂａ，Ｃａ，Ｓｂ和Ｓｅ与碳酸盐矿物有关．此外，还预测了Ａｓ，Ｂｅ，Ｃｒ，Ｃｕ。

Seven channel samples collected from Shenbei coalfield of Liaoning Province were determined by inductively coupled plasma atomic emission spectroscopy (ICP AES) and instrumental neutron activation analyses (INAA). These analyses show that the contents of most elements in the samples are “normal”. Compared with average values for coals from China, US, and the world, the mass fractions of Co,Cr,Cu and Ni(23.27×10 -6 ,85.80×10 -6 ,69.07×10 -6 and 80.60×10 -6 ,respectively, whole coal basis) from Shenbei coalfield are in the high side. The elements As, Co, Cu and Ni are enriched (EF>5) in coal of Shenbei coalfield. The associations of 22 elements were analyzed by correlation matrix, cluster analysis and scanning electron microscopy (SEM) combined with energy dispersive X ray analyzer (EDX). We find that Co, Mo and Sn in coals are associated with clay; Be, Br, P, Mn and V in coals are organically associated; As, Pb, Th, V and Zn in coals are found in pyrite; while Cr, Cu and Ni probably are associated with pyrite. We also predicted the depressed efficiency of some trace elements by conventional coal cleaning process, such as As, Be, Cr, Cu, Ni, Zn, etc.