The Leaching Characters Of Typical Chinese Coal With High As, Hg Contents

Releasing harmful elements by the utilizing process of coals lead to environment pollution and people's increasing attention, and the As and Hg are intensely concerned about. The contents of As and Hg are high in some Chinese coal, and they do have heavy influences on environments with the rain leaching and coal refuse accumulation.The coal, coal refuse, and power plant ash with high As and Hg contents were researched, and then, environment influences on soil and water are investigated. Based on the leaching experiment, the precipitation regularity of As and Hg is analyzed. Systematic analyzd the leaching characters with different solution, conditions, and time in this paper.In order to choose classic coal samples with high As and Hg contents, the main Chinese mine coals are analyzed. The results show that coal samples have extensive distribution, and it doesn't have complete correlation with As and Hg contents. The soil and water around mine with high As an Hg contents are researched, it shows that the mine and coal refuse won't influence the environment, but the ash flushing water of power plant will pollute the water around.There are two parts leaching experiments in this paper, which are batch leaching and column leaching. The results of the experiments indicate that the change of As and Hg contents in leachate are correlative negatively to the change of pH value, and the concentrations are far below that of GB. But in the column leaching experiment of extra-high As and Hg samples, the leachate concentrations are higher than GB.Acids have great influence on the column leaching, and in the simulated rainfall leaching experiment, it should take more consideration of organic influences on leachate.It is possible to decline the As and Hg concentration of leachate in the coal-soil leaching , but in the long time leaching, the As and Hg contents would be saturated, and the soil quality would be changed.