| 反复冻融与高温老化对砷污染土壤固化稳定化效果的影响 |
| 摘要点击 2601 全文点击 1029 投稿时间：2017-04-10 修订日期：2017-05-22 |
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| 中文关键词 高温老化 反复冻融 砷 污染土壤 固化/稳定化 |
| 英文关键词 high temperature aging repeated freezing and thawing arsenic contaminated soil solidification and stabilization |
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| 中文摘要 |
| 通过无侧限抗压强度、渗透系数、浸出浓度以及形态分布测试，分别考察了不同条件下反复冻融和高温老化作用对砷污染土壤固化或稳定化效果的影响，同时利用扫描电镜分析了稳定化土壤的微观形貌变化.结果表明，反复冻融和高温老化处理均会不同程度地削弱固化土壤的抗压强度，并提高其渗透系数.两种处理会增加稳定化土壤中砷的不稳定形态，从而增大其浸出浓度，如反复冻融处理300次后，稳定化土壤中砷的不稳定形态增加了19.81%，浸出浓度由115.5μg·L-1增加至151.5μg·L-1，80℃高温老化10 h后，砷的不稳定形态增加了25.1%，浸出浓度增加至164.5μg·L-1.反复冻融次数的增加、老化温度的升高以及老化时间的延长，均会分别增大对固化/稳定化效果的影响.稳定化土壤经反复冻融和高温老化处理后，会发生不同程度的碎裂，呈现结构松散状. |
| 英文摘要 |
| The impact of solidification and stabilization effects on arsenic (As) contaminated soil before and after repeated freezing and thawing or high temperature aging was investigated by tests of unconfined compressive strength (UCS), permeability, leaching concentration and fractionation. The microstructure appearance of the soil was observed using SEM. The results show that the UCS of solidified soil decreases and its permeability increases after repeated freezing and thawing or high temperature aging. In stabilized soil, the unstable species of As increase and the leaching concentration of As rises accordingly after both treatments. The concentration of unstable species of As increased accordingly by 19.81% and 25.1%, and the leaching concentration rose from 115.5 μg·L-1 to 151.5 μg·L-1 and 164.5 μg·L-1 respectively after 300 freeze-thaw treatments or under 10 h of high temperature aging under 80℃. In general, the influence of the effects increases with more freeze-thaw events and higher temperature aging of longer duration. More damage and fragmentation was observed after both treatments. |
