煤矸石中金属和酸根离子的淋溶特性  

The leaching characteristics of metals and acid radical ions in gangue

作　　者：张燕青[1] 黄满红[1] 戚芳方[1] 杜勇立[2] 

机构地区：[1]东华大学环境科学与工程学院,上海201620 [2]湖南省交通规划勘察设计院,长沙410008

出　　处：《环境化学》2014年第3期452-458,共7页Environmental Chemistry

基　　金：国家自然科学基金(21007010);湖南省交通厅科研项目(200908;201105);交通运输部科技项目(2010353343290)资助

摘　　要：为了确定煤矸石的污染析出特性及规律,以某高速公路的煤矸石为研究对象,通过实验室模拟大自然降雨的过程,并控制实验过程中的浸泡时间、pH、固液比及空隙率,对煤矸石进行淋溶实验.结果表明,在静态浸泡实验中,污染物浸出量随浸泡时间的延长而增大,48 h污染物析出达到平衡;煤矸石中污染物的浸出量随初始pH值的降低而增大;随固液比的增大而增大.煤矸石空隙率越小,污染物析出的质量浓度越高.在模拟自然降雨的第一次淋溶过程中,煤矸石中浸出的污染物质量浓度最大,从第二次的淋溶过程开始,污染物的释放量便迅速下降,并保持较平稳的溶解释放速率.实验结果说明,降雨次数和降雨量的增加会促进煤矸石中污染物的溶解释放.在煤矸石中混合黏土、砂砾等增加煤矸石的空隙率,可以降低污染物析出量,从而减轻煤矸石资源化利用中对沿线土壤和地下水的二次污染.To figure out the leaching characteristics of pollutants in gangue, samples taken along a highway were chosen as the research objectives. It is necessary to simulate natural rainfall in the laboratory, performing static and dynamic leaching experiments involving changing the soaking time, pH, solid-liquid ratio and porosity ratio. In the static soaking experiment, when the soaking time was prolonged, there were more pollutants dissolving and releasing in the waters with an equilibrium time of 48 hours. Meanwhile, more pollutants released from gangue as the initial pH was lower and the solid-liquid ratio was higher. The less the porosity ratio of gangue, the higher pollution mass concentration would be. The pollution concentration in the first leaching process was very high while sharply declining from the second process. The releasing amount soon stabilized at a relatively low rate by the eighth process. The results indicated that the increasing of rainfall times and capacity promotes the pollution dissolving and releasing from gangue. Blending clays and gravels in the gangue could enhance the porosity ratio and lessen the amount of pollutants released, thus, reducing the secondary contamination pollution to the soil ant] ~r,~,,n~ ,,,~r

关 键 词：煤矸石 动态淋溶 金属离子 酸根离子 空隙率 固液比 

分 类 号：TD849.5[矿业工程—煤矿开采]