重金属污染土壤化学淋洗修复室内试验研究
Laboratory Study on Chemical Leaching Remediation of Heavy Metal Contaminated Soil
韩君1
作者信息
- 1. 上海利元环保检测技术有限公司,上海 201100
- 折叠
摘要
针对上海虹口区某受重金属污染地块开展淋洗研究,淋洗剂选择为盐酸、柠檬酸、草酸、琥珀酸以及EDTA溶液,研究不同淋洗剂类型、淋洗液浓度、水土比、淋洗时长对淋洗去除率的影响,试验结果表明:柠檬酸浓度为 0.5～2.0 mol/L,土水比为 1 ∶ 10～1 ∶ 15,淋洗时间为 4～6 h,淋洗后的四种重金属质量比均低于修复目标值,从经济性角度考虑,推荐使用 0.5 mol/L柠檬酸作为淋洗剂,土水比为 1 ∶ 10,淋洗时间为 4h,淋洗次数为 1 次.淋洗后土壤生石灰添加量比例为 1.5%时,土壤pH值可调节至 6～9 范围内.淋洗废水使用 7%PAC与 1‰PAM组合作为絮凝剂处理,出水COD浓度可达到排放标准.
Abstract
A heavy metal contaminated plot in Hongkou District of Shanghai was studied.The eluent of choice is hydrochloric acid,citric acid,oxalic acid,succinic acid and EDTA solution.The effects of different eluent types,eluent concentration,water and soil ratio and eluent duration on eluent removal rate were studied.The experimental results showed that the concentration of citric acid was 0.5～2.0 mol/L,the ratio of soil to water was 1 ∶ 10～1 ∶ 15,and the leaching time was 4～6 h.The concentrations of four heavy metals after leaching were all lower than the repair target value.From the economic point of view,it is recommended to use 0.5 mol/L citric acid as leaching agent,soil-water ratio of 1 ∶ 10,leaching time of 4 h,and leaching times of 1 time.The pH value of the soil can be adjusted to the range of 6～9 when the proportion of quick lime is 1.5%.The leaching wastewater is treated with the combination of 7%PAC and 1‰PAM as flocculant,and the effluent COD concentration can meet the discharge standard.
关键词
重金属污染土壤/化学淋洗修复/室内试验Key words
heavy metal contaminated soil/chemical leaching repair/laboratory test引用本文复制引用
出版年
2024
NETL
NSTL
万方数据