Geochemical Characteristics Of The No.4 Coal In Heshan Coalfield

The associated elements in coal play an important role in the utilization of coal resources,which not only provides data support for the study of coal-forming sedimentary environment,but also provides a theoretical basis for the extraction of beneficial trace elements in coal.Recent studies have found that rare elements are enriched in the Heshan coalfield in Guangxi.This project selects No.4₂ coal in Heliluoshan Mine and No.4₁ coal-carboniferous-Permian coal seam in Shicun Coal Mine as research object,with element geochemistry,coal geology,minerals.As a guide,the theory of science and coal lithology,using X-ray fluorescence spectroscopy,scanning electron microscopy with energy spectrum,polarized light microscope,X-ray diffraction,inductively coupled plasma mass spectrometry,etc.,9 samples and Hecun in Heliluoshan Mine The geochemical characteristics of 12 samples from the mine were initially discussed and studied.The results show that the No.4₂ coal in Heliluoshan Mine and Shicun Mine is composed of bright and dark coal.The shale or silk charcoal strips are mainly semi-bright coal-semi-dark coal type,and a few high ash.The parts are dark coal type,the micro-coal rock components are mainly vitrinite group?58.54%and 62.69%?,followed by the inertia group?28.57%and 27.81%?,and no chitin group is found in the two mines.The reflectance R_o of the vitrinite group was 1.775%and 1.807%,respectively,which belonged to high-order bituminous coal.The associated minerals in the Heluoshan Mine and Shicun Coal Mine are mainly kaolinite,quartz,pyrite and calcite,and plagioclase,anorthite,albite,potassium feldspar,zircon,rutile,etc.Clay minerals are deposited at the same time because of the main;carbonate minerals are mainly hydrothermal genesis,which are affected by magma intrusion during formation;sulfide minerals are mainly composed of pyrite;oxide minerals are mainly composed of quartz,and quartz minerals are mainly terrestrial quartz crumbs,quartz minerals are mainly based on terrestrial quartz crumbs.Comparing the content of associated elements in coal with the background values of elements in the upper crust,Chinese coal and world coal,it can be seen that the elements Mo and U in No.4₂ coal of Heliluoshan Mine in are abnormal enrichment levels,and Cs and Zr are enriched.Level;the elements Li and Zr in No.4₁ coal of Shicun Mine belong to the enrichment level.The average values of rare earth elements in the coals of Shicun Mine and Heliluoshan Coal Mine are higher than the Chinese value,world value,US value and upper crust value.The content of rare earth elements in No.4₁ coal seam of Shicun Mine is higher than that of Heliluoshan Coal Seam.No.4₂ coal in Shicun Mine is rich in light and medium-sized rare earth,and Heliluoshan Mine is rich in light rare earth.The source of trace elements in No.4₁ coal of Shicun Coal Mine is terrigenous clastic rock,the coal-forming environment is sea-land interaction phase,and the medium sedimentation is dominated by reducing conditions;the No.4₂ coal in Heliluoshan Mine was invaded by magma during coal formation.As well as the corrosive effects of seawater,Media deposition is dominated by weak oxidative conditions.