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

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.

Keywords

• heavy metal；chromium
• unconfined compressive strength
• toxicity leaching test
• microscopic analysis