重金属锌污染淤泥质粉质粘土物理特性试验研究

Study on the Physical and Electrical Properties of Silty Clay Contaminated by Heavy Metal Zinc

重金属污染在我国已受到普遍关注,而对重金属污染土的物理特性的研究还处于起步阶段。采用南京地区特有的粉质粘土、长江漫滩相淤泥质粉质粘土,进行相关的重金属锌污染后的物理特性研究。通过室内添加硝酸锌溶液配制3种不同浓度的重金属锌污染土,并进行土壤污染前后粒度成分、液塑限、活动度、土粒比重以及pH值等试验的测试分析,研究比较了粉质粘土污染前后随着重金属锌的浓度不同其相关物理性质的变化规律。试验表明,随着Zn浓度的增加,土粒比重,液塑限,粉粒含量和pH值减小,而粘粒含量和塑性指数呈增大趋势。其土体的活动度也随着Zn浓度的增加在不断的降低,并且降低趋势逐渐减缓。

More and more attention has been paid to the effects of heavy metal pollution of soil in China,but the study on physical properties of the heavy metal contaminated soil is still at the preliminary stage. The related physical properties will change when the soil was contaminated by heavy metal. The muddy silty clay of floodplain in Changjiang River,which is unique in China,was used to study the physical properties of heavy metal-Zn contaminated soil.In this article,heavy metal-Zn contaminated soils with three different concentrations were prepared by adding the solution of zinc nitrate hexahydrate. Besides,the fines content test,specific gravity test,liquid plastic limit test,mobility test,pH test and resistivity test were taken to analyze the variation rules of relevant physical and electrical properties in heavy metal-Zn contaminated soil. It was shown in the test that the specific weight of soil particle,the liquid plastic limit,the silt content and pH decreased but the clay content and the plastic index increased with the increase of the Zn concentration.