摘要
以上海市某建设用地中的重金属污染土壤为研究对象,通过化学淋洗技术对污染土壤进行淋洗,优化了淋洗条件,研究了淋洗后不同粒径组分中的重金属含量分布规律。结果表明,在盐酸、柠檬酸和乙二胺四乙酸(EDTA)这3种淋洗剂对重金属镍、铜、铅的淋洗试验中,盐酸的淋洗效果最好,最佳淋洗浓度为0.3 mol/l,最佳淋洗时间为60 min,对土壤中镍、铜、铅的去除率分别为46%、74%、78%,其中镍的去除率较低是由于镍的本底浓度过高所导致。粒径分级试验结果表明,经盐酸和去离子水淋洗后的土壤中,重金属主要分布在粒径小于0.075 mm的土壤中;相比于去离子水,盐酸淋洗后,土壤颗粒的分散程度得到提高,从而对土壤颗粒中的重金属进行有效去除。
In order to study the distribution of heavy metal content in different particle size fractions after leaching, the heavy metal contaminated soil in a construction land in Shanghai was taken as the research object, and the leaching conditions of contaminated soil were optimized. The results showed that hydrochloric acid had the best leaching effect on nickel, copper and lead in the soil. The optimal leaching concentration was 0.3 mol/L and the optimal leaching time was 60 minutes. The removal rates of nickel, copper and lead in soil were 46%, 74% and 78%, respectively. The low removal rate of nickel was due to the high background concentration of nickel. The results of particle size classification test showed that the heavy metals were mainly distributed in the soil with particle size less than 0.075 mm after leaching with hydrochloric acid and deionized water. Also, compared with deionized water, the dispersion degree of soil particles was improved after leaching with hydrochloric acid, so that the heavy metals in soil particles could be effectively removed.
作者
宋刚练
江建斌
梅皓天
鞠振宇
何静
马雪瑞
SONG Gang-lian;JIANG Jian-bin;MEI Hao-tian;JU Zhen-yu;HE Jing;MA Xue-rui(Shanghai Geological and Mineral Engineering Investigation(Group)Co.,Ltd.,Shanghai 200072,China;Shanghai Geological Construction CO.,Ltd.,Shanghai200436,China;Shanghai Geotechnical Engineering Testing Center CO.,Ltd.,Shanghai 200436,China)
出处
《地质灾害与环境保护》
2022年第4期115-120,共6页
Journal of Geological Hazards and Environment Preservation
关键词
重金属
污染土壤
淋洗
粒径分级
heavy metals
contaminated soil
leaching
size grading
