ISSN 1000-3665 CN 11-2202/P

    电镀场地重金属铬污染土固化率及稳定性研究

    A study of the curing rate and stability of heavy metal chromium contaminated soil at electroplating sites

    • 摘要: 为了解决宁波地区电镀场地重金属污染问题,研究利用自配固化剂开展铬污染土的毒性浸出试验、无侧限抗压强度试验、动荷载作用下的长期稳定性试验以及扫描电镜试验。在此基础上分析固化土的力学特性、浸出特性等随养护龄期、固化剂掺量、固化剂配比、铬污染水平的变化规律。结果表明:自配固化剂对铬污染土的固化率均达85%以上,固化率大体上随固化剂掺量增加而增大,随铬浓度上升而下降,随养护龄期的增加先上升后下降;固化铬污染土的无侧限抗压强度随龄期和固化剂掺量的增加而增大,随铬浓度的增加而降低;相对于施加动荷载作用前,经过28,90 d养护的固化土在长期动荷载后的固化率及无侧限抗压强度均有小幅度下降,但各因素的影响规律不变。试验表明自配固化剂对铬有很好的固化效果,研究所得各影响因素的变化规律可为固化和修复重金属污染的电镀场地提供理论支持。

       

      Abstract: In order to solve the problem of heavy metal pollution at electroplating sites in Ningbo, toxic characteristic leaching procedure, unconfined compressive strength test, long-term stability test under dynamic load and scanning electron microscope test of chromium-contaminated soil were carried out by using self-formulated curing agent. On this basis, the change patterns of the mechanical properties and leaching characteristics of the cured soil with the maintenance age, curing agent dosing, curing agent ratio and heavy metal contamination level are analyzed. The results show that the curing rate of chromium-contaminated soil with self-formulated curing agents is more than 85%, and curing rate increases with the amount of curing agent, decreases with the concentration of chromium, and increases with the age of maintenance and then decreases. The curing rate and unconfined compressive strength of the cured soil after 28, 90 d curing compared with those before the application of dynamic load show a small decrease, but the influence pattern of each factor remained the same. The self-formulated curing agents have a good curing effect on chromium. This research may provide theoretical support for curing and remediation of contaminated electroplating sites based on the analysis of the variation pattern of each factor variable.

       

    /

    返回文章
    返回