摘要
为提高淋洗实验对工程应用实施的指导性,以柠檬酸为淋洗剂对某电镀厂Cu、Ni复合污染土壤展开了修复研究。结果表明:土壤粒径越大,Cu、Ni质量分数越低,淋洗去除率越高,粒径大于0.25 mm土壤可直接利用去离子水淋洗达标;正交实验确定的最佳淋洗条件为液固质量比5∶1、柠檬酸溶液摩尔浓度0.2 mol·L^(-1)、淋洗时间1 h,砂土中Cu、Ni淋洗去除率分别达到88.97%、72.74%;Cu、Ni的淋洗去除率从高到底依次为砂土、粉质黏土、淤泥质黏土;Cu、Ni的淋洗去除率随土壤污染强度的增大而升高;第一次淋洗不达标土壤经第二次淋洗后均达标,Cu、Ni的第二次淋洗去除率远低于第一次,Cu的第二次淋洗去除率低于Ni;Cu、Ni弱酸提取态、可还原态及可氧化态的淋洗去除率均明显高于残渣态。
In order to improve the guidance of washing experiment for engineering application,a study on remediation of copper and nickel composite contaminated soil in an electroplating plant was carried out using citric acid as washing agent.The results showed that,the larger soil particle size would lead to lower soil mass fractions of copper and nickel and higher washing removal rates,the soil with particle size greater than 0.25 mm could be directly washed with deionized water to reach the standard.The optimal washing conditions determined by orthogonal experiment were as follows:liquid to solid mass ratio 5∶1,citric acid molar concentration 0.2 mol·L^(-1),washing time 1 h,the washing removal rates of copper and nickel in sand reached 88.97% and 72.74%respectively.The washing removal rates of copper and nickel from high to low were as follows:sandy clay,silty clay and muddy clay.The washing removal rates of copper and nickel increased with the increase of soil pollution intensity.The soils that did not meet the standard in the first washing reached the standard after the second washing,the second washing removal rates of copper and nickel were much lower than that of the first washing,and the second washing removal rate of copper was lower than that of nickel.The washing removal rates of weak acid extractable,reducible and oxidizable states of copper and nickel were obviously higher than that of residual state.
作者
罗成成
LUO Cheng-cheng(Shanghai Shenhuan Environmental Engineering Co.,Ltd.,Shanghai 200092,China;Shanghai Municipal Engineering Design Institute(Group)Co.,Ltd.,Shanghai 200092,China)
出处
《当代化工》
CAS
2023年第4期852-857,共6页
Contemporary Chemical Industry
基金
上海市在产工业用地土壤与地下水污染原位管控修复技术研究(沪环科[2022]第16号)。
关键词
铜镍污染土壤
柠檬酸
土壤淋洗
去除率
Copper and nickel contaminate soil
Citric acid
Soil washing
Removal rate
