宁东煤田中部侏罗纪煤的矿物学特征

Mineralogical of the Jurassic coals in the middle of Ningdong Coalfield

  • 摘要: 样品采自鄂尔多斯盆地西部宁东煤田的7个井田,共26个样品,包括25个煤样和1个矸石样。对所采的25个煤样做了工业分析、全硫分析和发热量分析,并运用低温灰化-X射线衍射(LTA-XRD)仪、光学显微镜、扫描电镜(SEM)以及能谱仪(EDS)等设备对样品矿物成分、化学成分、微形貌特征等方面进行了研究,探讨了煤中矿物的物质来源。研究表明,宁东煤田中部侏罗纪煤属中等挥发分煤,具有中灰、低硫、中低发热量的特征,其(低温灰化后)矿物组成为:33.1%高岭石、22.8%伊利石、21.5%石英、13.2%钠长石、6.6%鲕绿泥石、2.8%方解石。另外在扫描电镜下还发现了极少量的黄铁矿、菱铁矿、钛铁矿、黄铜矿、锆石。高岭石、伊利石、鲕绿泥石、石英、钠长石源自贺兰山脉片麻岩、麻粒岩和花岗岩的风化产物。

     

    Abstract: 26 samples,including 25 coal-seam samples and one parting,were collected from 7 mines in Ningdong- Coalfield,Ordos Basin,China. Proximate,total sulfur and gross calorific value were analyzed of the 25 coal samples. The composition,chemical composition and micro-topography of samples were studied by low-temperature ashing-X-ray diffraction (LTA-XRD),optical microscopy,scanning electron microscopy (SEM) and energy dispersive spectroscopy ( EDS). The sources of minerals in coal were discussed. The results indicate that Jurassic coal in middle part of Ning- dong Coalfield is a medium volatile bituminous coal,with medium-ash,low-sulfur and low-medium calorific,the miner- al composition (low temperature ashes) is as follows:33. 1% kaolinite,22. 8% illite,21. 5% quartz,13. 2% albite, 6. 6% chamosite,2. 8% calcite. In addition,a trace of pyrite,siderite,ilmenite,chalcopyrite,zircon also found by the scanning electron microscope. Kaolinite,illite,chamosite,quartz,and albite are origin from weathering productions of gneiss,granulite and granite in HelanMoutain.

     

/

返回文章
返回
Baidu
map