滇东北镇雄煤田晚二叠世煤中硫的可选性

Washability of sulfur in Late Permian coal from Zhenxiong coalfield, northeastern Yunnan

通过对云南省东北部昭通市镇雄干沟乡荣兴煤矿C5煤层原煤筛分浮沉实验的研究,分析了该煤层中全硫及形态硫在不同粒度级和密度级中的分布规律。结果显示,全硫和黄铁矿硫在各粒度级煤中分布较均匀,其含量在各密度级煤中的分布随密度级的增大而增大。该煤层的破碎解离性质较差,但其粒度小于3.0 mm时,可分离出含2.35%全硫的浮煤(浮煤产率达88%)。总体来看,高密度级中,黄铁矿硫>95%;低密度级中,黄铁矿硫<65%,有机硫占30%左右,但其全硫较低。因此,可通过物理方法使浮煤中的硫分降低。

The screening and sink-and-float tests of raw coal have been carried out on the No.C5 coal in the Zhenxiong coalfield, northeastern Yunnan, with the samples from the Rongxing coal mine at the Gangou Town of the Zhaotong City. Distribution of sulfur in different density grading and size grading of coal is studied. The results show that the levels of the total sulfur and pyritic sulfur vary little in different size grades of coal, but in a same size grade the sulfur content increases with the density grades. In addition, the proportion of pyritic sulfur in the total sulfur is increasing with the sizes. The properties of crushing and separation of this coal are poor as the sulfur contents are relatively constant during the whole crushing process. However, the float coal with 2.35% total sulfur can account for 88% when size less than 3.0 mm. Generally pyritic sulfur is the most important form of sulfur in the high density grades, accounting for 95% in total sulfur, and this figure drops down to less than 65% in the light density grades in which the organic sulfur can take up to 30% although the total sulfur is low. In conclusion, physical methods can be used to reduce the sulfur in float coal.