摘要
采用振荡淋洗方法对三种粒径(+2mm、-2mm+0.15mm、-0.15mm)某尾矿库周边铀污染土壤进行去污试验,选用盐酸、硝酸、柠檬酸、草酸为淋洗剂,通过控制淋洗浓度、液固比、时间、温度、混合淋洗等因素来确定较优的淋洗条件。结果表明:各淋洗剂对铀污染土壤的去污效果为草酸>盐酸>硝酸>柠檬酸;当淋洗浓度大于0.5mol/L、淋洗时间大于8h或液固比大于10∶1时,其淋洗效果都逐渐趋于稳定;提高淋洗温度可显著提升淋洗效果;选用草酸+盐酸和草酸+硝酸两组较优混合淋洗组合对全粒径土壤进行淋洗时,土壤中铀去除率均达50%以上,总含铀量分别降至27.15、24.32mg/kg,均达到土壤修复目标(40mg/kg)。
Oscillation leaching method was applied to conduct decontamination experiment for three kinds of particle size(+2mm,-2mm+0.15mm,-0.15mm)of contaminated soils surrounding uranium tailings.The optimum leaching conditions were obtained by single factor test through selection of hydrochloric acid,nitric acid,citric acid,and oxalic acid as eluting agent,and by controlling elution concentration,L/S,time,temperature,and mixture elution.The results show that removal effect of leaching agent on uranium contaminated soil is oxalic acid>hydrochloric acid>nitric acid>citric acid.When leaching concentration is 0.5mol/L above and leaching time is 8h above or L/S>10/1,elution effect gradually tends to be stable.Elution effect can be significantly improved by increasing leaching temperature.When two groups of oxalic acid+hydrochloric acid and oxalic acid+nitric acid are selected for elution agent,uranium removal rate in soil with full grain size is 50% above,and total uranium content drop to 27.15 and 24.32mg/kg respectively,all of which reaches the soil remediation target(40mg/kg).
作者
沈威
高柏
章艳红
张海阳
牛天洋
杨冰
连国玺
SHEN Wei;GAO Bai;ZHANG Yan-hong;ZHANG Hai-yang;NIU Tian-yang;YANG Bing;LIAN Guo-xi(School of Water Resources and Environmental Engineering,East China University of Technology,Nanchang 330013,China;State Key Laboratory of Nuclear Resources and Environment,East China University of Technology,Nanchang 330013,China;The Fourth Research and Design Engineering Corporation of CNNC,Shijiazhuang 050021,China)
出处
《有色金属（冶炼部分）》
CAS
北大核心
2019年第11期81-86,共6页
Nonferrous Metals（Extractive Metallurgy)
基金
国家自然科学基金资助项目（41162007,41362011）
江西省重点研发计划项目（20181ACG70023）
河北省重点研发计划项目（18274216D）
关键词
放射性核素
铀污染土壤
粒径
混合淋洗
radionuclide
uranium contaminated soil
soil particle size
mixture elution
