霍西煤田不同密度煤中常微量元素地球化学特征
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摘要
以霍西煤田灵石矿区10号煤不同密度煤样为研究对象,采用原子荧光光谱法(AFS),X射线荧光光谱法(XRF)、电感耦合等离子质谱法(ICP-MS)等方法测定样品的常、微量元素质量分数;运用数理统计方法分析了煤中常微量元素在不同密度煤中的分布规律,并探讨了不同密度煤中微量元素的赋存特征。研究结果表明,霍西煤田10号煤为中-高硫煤,有机硫含量较高。煤中Mo,Cd,Sb,U和As属超富集元素;Li,W,Pb和Bi为富集元素。微量元素Li,Bi,Tl,Sb,As,Mo,Pb,Cd,U,Th和Hf的含量随样品密度的增大均呈现不同程度的递增趋势;Be变化平稳,W表现为先递增后降低的分布特征。元素Mo,U,Sb,Cd和Bi主要以硅酸盐(黏土)矿物吸附态存在;Pb和As与硫化物矿物有关;Si,Ti,Li和Th具有磷酸盐和铝硅酸盐亲和性;Sr和Y偏于碳酸盐亲和性和硅酸盐亲和性;Hf和Zr主要赋存于矿物中;Be和W具有较强的有机亲和性。
Takes the different density coal samples from No.10 coal in Huoxi coal field for investigating the distribution and occurrence of major and trace elements.The atomic fluorescence spectrometry( AFS),X-ray fluorescence spectrometry( XRF),inductively coupled plasma mass spectrometry( ICP-MS) and other methods were used to test the content of elements.The mathematical statistical method was applied to analyze the elements occurrence.The results show that the Mo,Cd,Sb,U and As are distinct enrichment,Li,W,Pb and Bi are the relative enrichment.The elements content of Li,Bi,Tl,Sb,As,Mo,Pb,Cd,U,Th and Hf are increased,Be is relative stable and W is increased firstly and decreased again with the density increase of coal samples in different density samples.Correlation analysis shows that Mo,U,Sb,Cd and Bi mainly occur in silicate mineral adsorption.Pb and As are related to sulfide minerals; Si,Ti,Li and Th have phosphate and aluminum silicate affinity.Hf and Zr may mainly occurs in zircon,and Be and W have a distinct organic affinity.
Takes the different density coal samples from No.10 coal in Huoxi coal field for investigating the distribution and occurrence of major and trace elements.The atomic fluorescence spectrometry( AFS),X-ray fluorescence spectrometry( XRF),inductively coupled plasma mass spectrometry( ICP-MS) and other methods were used to test the content of elements.The mathematical statistical method was applied to analyze the elements occurrence.The results show that the Mo,Cd,Sb,U and As are distinct enrichment,Li,W,Pb and Bi are the relative enrichment.The elements content of Li,Bi,Tl,Sb,As,Mo,Pb,Cd,U,Th and Hf are increased,Be is relative stable and W is increased firstly and decreased again with the density increase of coal samples in different density samples.Correlation analysis shows that Mo,U,Sb,Cd and Bi mainly occur in silicate mineral adsorption.Pb and As are related to sulfide minerals; Si,Ti,Li and Th have phosphate and aluminum silicate affinity.Hf and Zr may mainly occurs in zircon,and Be and W have a distinct organic affinity.
引文
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[20]代世峰,任德贻,李丹,等.贵州大方煤田主采煤层的矿物学异常及其对元素地球化学的影响[J].地质学报,2006,80(4):589-597,617.DAI Shifeng,REN Deyi,LI Dan,et al.The mineralogical anomaly of the main coal seam in Guizhou Province and its influence on the elemental geochemistry[J].Acta Geologica Sinica,2006,80(4):589-597,617.
[21]赵继尧,唐修义,黄文辉.中国煤中微量元素的丰度[J].中国煤田地质,2002,14(S1):6-14,18.ZHAO Jiyao,TANG Xiuyi,HUANG Wenhui.Abundance of trace elements in Chinese coal[J].Coal Geology of China,2002,14(S1):6-14,18.
[22]吴江平.淮南煤田东部煤中微量元素及其环境意义研究[D].淮南:安徽理工大学,2006.WU Jiangping.Study on the trace elements and environmental significance of coal in the east of huainan coalfield[D].Huainan:Anhui University of Science&Technology,2006.
[23]TAYLOR S R.Abundance of chemical elements in the continental crust:A new table[J].Geochim.et Cosmochim.Acta,1964,28:1273-1285.
[24]王文祥.煤中伴生元素的地球化学指相研究[J].煤炭学报,1996,21(1):12-17.WANG Wenxiang.The geochemistry of the associated elements in coal[J].Journal of China Coal Society,1996,21(1):12-17.
[25]宋党育,张晓逵,张军营,等.煤中有害微量元素的洗选迁移特性[J].煤炭学报,2010,35(7):1170-1176.SONG Dangyu,ZHANG Xiaokui,ZHANG Junying,et al.The removal and migration characteristics of harmful trace elements in coal[J].Journal of China Coal Society,2010,35(7):1170-1176.
[26]么秋香,杜美利,王水利,等.黄陇煤中微量有害元素的赋存与洗选洁净潜势[J].西安科技大学学报,2012,32(2):214-220,227.ME Qiuxiang,DU Meili,WANG Shuili,et al.The occurrence of trace harmful elements in Huanglong coal and the potential of cleaning and cleaning[J].Journal of Xi’an University of Science and Technology,2012,32(2):214-220,227.
[27]许琪,韩德馨,金奎励,等.煤中49种元素含量与煤岩组分和煤化程度的相关规律[J].中国矿业大学学报,1990,19(3):51-60.XU Qi,HAN Dexin,JIN Kuili,et al.The correlation between the content of 49 elements in coal and the composition of coal and the degree of coal[J].Journal of China University of Mining&Technology,1990,19(3):51-60.
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