酸雨情况下高砷煤中砷的淋滤特征 -

对河北某地待开发高砷煤样进行淋滤实验,研究了煤粒大小、酸雨酸度、降雨量以及酸雨类型对原煤中砷的淋出规律的影响。结果表明:煤样中的砷在淋滤初期被酸性雨水大量淋出,之后淋出率逐渐减小。对煤样中砷的形态进行分析发现砷主要以硫化物结合态的形式存在,可溶态砷、有机态砷、残渣态砷含量较低。在淋滤过程中主要是可溶态砷被淋出,在有氧化性酸雨的条件下有很少量的硫化物结合态的砷溶出。总体结果表明此煤样虽属于高砷煤样,但在运输、储藏等过程中在酸雨淋滤条件下不会对环境水质造成污染。 Taking the high-arsenic coal in Hebei province as research object,carried out the leaching experiments.Investigate the effect of coal particle size,acid rain acidity,rainfall and acid rain type on the law of arsenic leaching out of the raw coal.The results show that,the leaching rate is high at the beginning of experiment,then gradually decrease.The arsenic exists mainly in the form of sulfide bound.The soluble arsenic,organic arsenic,residual fraction arsenic speciation in coal samples is few.In the leaching process,the soluble arsenic easily leach out,few sulfide bound arsenic dissolve in acid rain.The overall results show that,though the coal sample is high-arsenic one,it brings no contamination to environment during transport and storage under acid rain condition