水化氯铝酸钙与传统钝化剂降低土壤镉生态及健康风险的对比研究  

Comparative study between CaAl-Cl LDH and conventional immobilizing agents for reducing ecological and health risks of soil Cd

作　　者：陈晓晨 黄艺佳 赵桐 张福祥 赵琦[1] 陈禹西 张剑宇 张旭钏 肖艳春[5] 杨桂芳 Chen Xiaochen;Huang Yijia;Zhao Tong;Zhang Fuxiang;Zhao Qi;Chen Yuxi;Zhang Jianyu;Zhang Xuchuan;Xiao Yanchun;Yang Guifang(Fujian Provincial Engineering Research Center of Rural Waste Recycling Technology,College of Environment and Safety Engineering,Fuzhou University,Fuzhou 350108,China;School of Mathematics and Statistics,Minnan Normal University,Zhangzhou 363000,China;Jiangsu Longchang Chemical Co.,Ltd.,Rugao 226532,China;Maoyou Wood(Jiangsu)Co.,Ltd.,Rugao 226532,China;Institute of Agricultural Engineering,Fujian Academy of Agricultural Sciences,Fuzhou 350003,China;Fujian Key Laboratory on Conservation and Sustainable Utilization of Marine Biodiversity,Fuzhou Institute of Oceanography,Minjiang University,Fuzhou 350108,China)

机构地区：[1]福州大学环境与安全工程学院,福建省农村废弃物绿色循环技术工程研究中心,福州350108 [2]闽南师范大学数学与统计学院,漳州363000 [3]江苏隆昌化工有限公司,如皋226532 [4]茂友木材(江苏)有限公司,如皋226532 [5]福建省农业科学院农业工程技术研究所,福州350003 [6]闽江学院福州海洋研究院,福建省海洋生物多样性保护与永续利用重点实验室,福州350108

出　　处：《农业工程学报》2022年第19期219-226,共8页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家自然科学基金项目(41807116);福建省自然科学基金项目(2019J05035);大学生创新创业训练计划项目(28148,S202010386067);福建省农科院对外合作项目(DWHZ-2022-17)。

摘　　要：针对红壤、棕壤、褐土、黑土4种中国典型的Cd污染土壤,应用Ca(OH)_(2)、Ca(H_(2)PO_(4))_(2)以及层状双金属氢氧化物(Layered Double Hydroxides,LDHs)、水化氯铝酸钙(CaAl-Cl LDH)开展钝化修复,并从土壤Cd的生态风险和健康风险角度进行修复效果对比研究。分析钝化剂对土壤pH值、土壤Cd的赋存形态以及土壤Cd直接经口摄入的生物可给性的影响,并对修复机理进行深入探究。结果表明,在Ca(OH)_(2)、Ca(H_(2)PO_(4))_(2)和CaAl-Cl LDH各自相对最优施用量下,3种钝化剂均可显著降低土壤Cd的活性系数(P<0.05),平均降幅分别为16.1%、56.9%和29.2%,可降低土壤Cd的作物吸收量及Cd对周边生态环境的风险。此外,施用CaAl-Cl LDH能显著且更为有效地降低土壤Cd的生物可给性(P<0.05)及Cd对人体的健康风险,在胃和小肠阶段的平均降幅为19.2%和33.0%,其中胃阶段分别达到施用Ca(OH)_(2)和Ca(H_(2)PO_(4))_(2)的3.11和1.99倍,小肠阶段为5.99和2.72倍。该研究为Cd污染土壤钝化修复剂的开发、改进和选择提供了科学依据和参考。Soil Cadmium(Cd)has posed a great threat to ecological security and human health in recent years.The exposure under the direct oral ingestion of contaminated soils has been the main contributor of Cd to the human body.The immobilization is an advisable technology to reduce the activity and bioavailability of Cd for the remediation of the Cd-contaminated soil.However,several challenges still remain for conventional immobilizing agents,such as the limited and weak immobilization mechanism,low efficiency and stability.Fortunately,layered double hydroxides(LDHs)can be a new promising type of functional material with great adsorption capability on heavy metals.But,only a few studies were focused on the application of soil remediation,regardless of the potential application to the health risk of soil Cd.In this comparative study,two conventional immobilizing agents(Ca(OH)_(2) and Ca(H_(2)PO_(4))_(2))and one promising LDH(hydrocalumite,CaAl-Cl LDH)were used to remediate the soils with Cd contamination.Four typical soils(red soil,brown soil,cinnamon soil,and black soil)were collected from the cities of Fuzhou,Beijing,Nanjing,and Gongzhuling in China,and then artificially contaminated to the Cd concentration of 180 mg/kg.Subsequently,the three immobilizing agents were applied on the land under the pre-determined optimal patterns.Specifically,the mass ratios of Cd to the immobilizing agent were 1:100,1:500,and 1:1000,respectively.A comprehensive analysis was also made to determine the effects on the specific soil physicochemical property(soil pH),Cd fractionation(ecological risk),and oral bioaccessibility of soil Cd(health risk)after three-month immobilization.The relevant mechanisms were further explored.Note that there was no evaluation of the health risk of soil Cd using the total concentration of Cd in the soil,due to the overestimation.Furthermore,the Cd bioaccessibility was utilized from the advanced in vitro test,where a PBET model was modified referring to the IVG model.An accurate simulation was then achieved in t

关 键 词：土壤 污染 修复 镉 层状双金属氢氧化物 赋存形态 生物可给性 

分 类 号：X53[环境科学与工程—环境工程]