贵州某地煤中砷的赋存状态研究

Study on Modes of Occurrence of Arsenic in Coal from Guizhou Province

选取贵州省某地选煤厂入选原煤作为研究对象,采用电子探针及波谱、逐级化学提取和浮沉试验,对贵州某地煤中砷的赋存状态进行研究.结果表明:该地煤中砷含量严重超标,并且砷元素与黄铁矿有紧密的结合,其主要载体矿物是黄铁矿和高岭石;硫酸盐结合态是砷的主要赋存状态;砷主要分布在脉石矿物中,可以通过洗选的方式脱除,但是因为有机结合态砷的存在,必将存在洗选脱除极限.

Using electron probe microanalysis equipped with wavelength dispersive spectrometer,sequential chemical extraction procedure and float-sink experiment,the modes of occurrence of arsenic in mine run coal from coal preparation plant in Guizhou province was studied.The results indicate that the arsenic content in coal severely exceed the standard and the mode of occurrence of arsenic is closely associated with pyrite.The main carriers of arsenic were sulfide and silicates.Sulfide associated form is the dominated mode of occurrence of arsenic in coal.Arsenic is mainly distributed in gangue,in which can be removed by separation.However,the limit of removing arsenic from coal via coal preparation is existing because of the organically bounded form existence.