地层介质对垃圾渗滤液的pH缓冲性能研究.pdfVIP

环 境 科 学 Vo1．29．No．7 Ju1．，2008 ENVIRONMENTAL SCIENCE 地层介质对垃圾渗滤液的pH缓冲性能研究 刘莹莹，赵勇胜 ，董军，刘鹏，朱志国，孙艳 (吉林大学环境与资源学院，长春 13o026) 摘要：通过一维土柱穿透实验和静态实验，分别从空间和时间2方面研究了不同天然地层介质对垃圾渗滤液的pH缓冲性能． 结果表明，细砂、粉砂和粘土的本底 pH缓冲容量分别为79．9·pH～mmol／kg、207．5·pH～mmol／kg、456．4·pH‘。mmol／kg．受垃圾 渗滤液污染后，除细砂外，随着时间的延长、离污染源距离的减小，每种介质总的pH缓冲容量都逐渐减小；其中碳酸钙缓冲体 系的缓冲容量均逐渐增大；硅酸盐、阳离子交换缓冲体系的缓冲容量无明显变化；铝、氧化铁缓冲体系的缓冲容量逐渐减少， 但土壤铝缓冲体系的缓冲容量则呈现出先增大后减少的趋势．细砂各个缓冲体系的缓冲容量随时、空变化均呈现出略微增大 的趋势．4种介质对渗滤液的pH缓冲能力的顺序是：细砂粉砂粘土土壤．土壤、粘土对垃圾渗滤液有较好的pH缓冲性 能，同时对渗滤液中各种污染物的迁移、扩散也有较好的控制作用． 关键词：地层介质；垃圾渗滤液；pH缓冲；缓冲容量 中图分类号：X523 文献标识码：A 文章编号：0250—3301(2008)07 1948—07 pH Buffering Capacity of Geological Media on Landfill Leachate LIU Ying—ying，ZHAO Yong—sheng，DONG Jun，LIU Peng，ZHU Zhi—guo，SUN Yan (College of Environment and Resources，Jilin University，Changchun 130026，China) Abstract：The one—dimensional breakthrough soil column experiment and static experiment were constructed to investigate the spaciM and temporal pH buffering capacity of the four natural geological media．Experimental results indicate that the background pH buffering capacity of fine sand，sill sand and clay is 79．9‘pH-。mmol／kg，207．5。pH一 mmol／kg，456．4’pH一 mmol／kg respectively．With the time going on and the distance closer to the leaching source，for each medium which is contaminated by the landfill leachate，the total pH buffering capacity decreases，the buffering capacity of calcium carbonate buffering system decreases，the buffering capacity of the silicate and cation exchange buffering system have no obivous changes，and the buffering capacity of the aluminium and ferric oxide buffering system also decrease，but the soil’S buffering capacity of aluminium buffering system increases at first and then decreases．The temporal and spacial buffering c