Mineralogical and geochemical characteristics of the No. 6 coal in the Tanggongta Mine, Inner Mongolia, China

In this paper, the geochemical characteristics of the trace elements of the No. 6 coal seam from Tanggongta mine, Jungar Coalfield, were studied using the methods of an energydispersive X-ray spectrometer (SEM-EDX) analysis, X-ray powder diffraction (XRD), inductively coupled plasma mass spectrometry (ICP-MS) and X-ray fluorescence spectrometric (XRF) techniques. The content of sulfur ranges from 0.09% to 2.83% (1.09% on average). The ash is from 11.70% to 31.47% (20.72% on average), and the moisture is from 2.72% to 6.82% (4.72% on average). The main minerals are kaolinite, carbonate minerals and pyrite. Compared with the average values of Chinese coal, the contents of Ga, Cd, Tl, Li, Sr, and Ag are high. Compared with the values of world coal, Li and Sr are found at high levels. The distribution mode of the REE shows that LREE is concentrated, but HREE is relatively low. The Yinshan Oldland should be the most likely source of the coal’s Li. The bauxite of the Benxi formation could be another source of the coal’s Li in the NE Jungar Coalfield.

Abundance of Rare Earth Elements and Yttrium in Coals from the Guanbanwusu Mine, Jungar Coalfield, Northern China, and their Geological Implication

Inductively coupled plasma mass spectrometry (ICP-MS) was used to determine the concentrations of rare earth elements and yttrium (REY) in coal and associated rock samples from the Guanbanwusu Mine, Jungar Coalfield, Northern China. The Guanbanwusu coals have a similar vitrinite reflectance and sulfur content, and a slightly higher ash yield. The concentration of REY (from La to Lu plus Y) in the 6 coal of the Guanbanwusu Mine varies from 72 μg/g to 396 μg/g and averages 186 μg/g, higher than that in normal Chinese coal (136 μg/g) and much higher than that in average world hard coals. The H-type distribution patterns in the No. 6 coal (W9-2 and W9-9) were probably caused by stronger water influences than those in the other coalfield. The coal bench (W2 and W9) with L-type is because terrigenous input influence.