太原西山煤田煤系锂镓赋存特征及工业前景

Occurrence characteristics and industrial prospects of lithium and gallium in coal in Taiyuan Xishan coalfield

为研究太原西山煤田中锂镓元素的赋存特征及其工业边界品位,分析了西山煤田煤系地层锂镓分布特征和决定因素,讨论了煤和煤矸石锂、镓含量与Al_2O_3、高岭石、粒度的关系,并分析了西山煤田煤系锂镓的内蕴资源量和工业前景。研究认为,西山煤田煤中锂含量高于与全国煤中锂的平均值,煤中镓含量大于山西煤中镓平均值,但均小于煤中锂、镓的建议回收指标。煤层夹矸中锂、镓含量显著高于煤层,且大于煤中锂、镓的边界品位。垂向上,山西组煤的镓含量高于太原组。西山煤田煤中锂、镓和煤中Al_2O_3含量呈正相关关系,且较多地赋存于粗颗粒夹矸中,而在细颗粒夹矸中含量较少。夹矸中镓含量和高岭石含量呈正相关关系,但锂含量和高岭石关系不明显。西山煤田煤系地层锂、镓的内蕴资源量分别为2.39万t和7.10万t,在目前经济技术条件下,西山煤田煤中锂不具有工业开发价值,古交邢家社矿区山西组下部煤层和马兰矿区8号煤夹矸中镓接近煤和夹矸中镓的边界品位,具有潜在的工业价值。

In order to study occurrence characteristics of lithium and gallium and cut off grade in Taiyuan Xishan coalfield,the distribution characteristics and determinant of lithium and gallium in the coal-bearing strata of the Xishan coalfield were discussed.The relationship between lithium and gallium content of coal and gangue and Al2O3,kaolinite and granularity was analysed,and intrinsic storage capacity and industrial prospects in the coal-bearing strata of the Xishan coalfield were discussed. Research show that the lithium content in coal from Xishan coalfield is higher than the average value of lithium in coal from the country,and the content of gallium in coal is higher than the average value of Shanxi coal.The contents of lithium and gallium in coal gangue are significantly higher than those in coal seams,but they are lower than the recommended recovery index for lithium and gallium in coal.Vertically,the lithium content of coal in the Shanxi group is higher than that in the Taiyuan group,but this feature is not evident in the clips.Besides,the content of lithium and gallium shows a good positive correlation with Al2O3 content in coal,and mainly exsited in the coarse-grained material,while it is less in the fine-grained material.The intrinsic resources of lithium and gangue in the coal-bearing strata of the Xishan coalfield are 23 900 tons and 71 000 tons respectively.However,under current economic and technological conditions,lithium does not have industrial development value.The coal seam in the lower Shanxi Formation in the ancient Jiaojia Xingjiashe mining area and the No.8 coal field in the Malan mining area has a potential industrial value as it is close to the boundary grade between coal and medium saggers.It has significance for the development and utilization of coal and coal gangue in Xishan Coalfield.