FeSO_(4)联合固化剂修复铬污染土壤的稳定化研究  

Study on stabilization of FeSO_(4) combined curing agent to repair chromium contaminated soil

作　　者：任学昌[1] 张曦 时秋红 张玉杰 陈仁华 RENG Xue-chang;ZHANG Xi;SHI Qiu-hong;ZHANG Yu-jie;CHEN Ren-hua(College of Environmental and Municipal Engineering,Lanzhou Jiaotong University,Lanzhou 730070,China)

机构地区：[1]兰州交通大学环境与市政工程学院,兰州730070

出　　处：《安全与环境学报》2022年第4期2231-2240,共10页Journal of Safety and Environment

摘　　要：利用FeSO_(4)联合多种固化剂修复铬污染土壤,并对修复后土壤的稳定性进行研究。基于Cr(Ⅵ)浸出试验、Tessier重金属形态提取试验、XPS表征分析,探究FeSO_(4)与多种固化剂(过磷酸钙、磷酸二氢钠、钙镁磷肥、氢氧化铝)在不同用量与不同添加顺序条件下对铬污染土壤的还原固化效果,为实际铬污染土壤修复工程提供理论依据和数据支持。结果表明,3.5×FeSO_(4)+10%钙镁磷肥与3×FeSO_(4)+10%氢氧化铝两步法处理效果最佳,Cr(Ⅵ)浸出质量浓度低于1.5 mg/L,且有机态与残渣态占比最高,是同剂量FeSO_(4)单独处理占比的1.349与1.34倍。此外,FeSO_(4)联合固化剂两步处理法效果整体优于同步处理法。In this experiment,FeSO_(4) was used as a reducing agent,combined with a variety of curing agents to repair chromium-contaminated soil.Based on the leaching of Cr(Ⅵ)experiment,Tessier morphology extraction experiment and XPS characterization analysis,the article analyzed the remediation effect of FeSO_(4) and seven curing agents(superphosphate,sodium dihydrogen phosphate,disodium hydrogen phosphate,calcium magnesium phosphate,aluminum oxide,aluminum hydroxide,kaolin)on the chromium-contaminated soil,and screened out the type of curing agent with good curing effect and the range of FeSO_(4) dosage.Then we explored the reduction curing effect of FeSO_(4) combined with various curing agents to repair chromium-contaminated soil under different adding order and dosage conditions,providing the theoretical basis and data support for the actual chromium contaminated soil remediation project through experimental research.The experimental results show that the dosage of FeSO_(4) is inversely proportional to the leaching mass concentration of Cr(Ⅵ)in chromiumcontaminated soil.Superphosphate,sodium dihydrogen phosphate,calcium-magnesium phosphate,and aluminum hydroxide alone have good solidification effects when treating chromium-contaminated soil,but disodium hydrogen phosphate,alumina,and kaolin alone have poor curing effects.The two-step treatment effect of 3.5×FeSO_(4) combined with 10%calciummagnesium phosphate fertilizer and 3×FeSO_(4) combined with 10%aluminum hydroxide are the best,and the leaching mass concentration of Cr(Ⅵ)reaches the pollution control index of chromium slag entering the domestic waste landfill in“Chromium Slag Pollution Treatment Environmental Protection Technical Specifications(Interim)(HJ/T 301—2007)”.After two-step processing,the ratios of organic state and residue state reach the maximum which are 1.349 and 1.34 times the proportion of the same dose of FeSO_(4) alone treatment.In addition,the effect of FeSO_(4) combined with curing agent two-step was far better than the simultane

关 键 词：环境工程学 铬污染土壤 FeSO_(4) 固化剂 联合修复 

分 类 号：X53[环境科学与工程—环境工程]