原位热修复热场地采样加标回收研究

Study on Labeling Recovery of Sampling in Hot Site of in-Situ Thermal Restoration

在污染地块原位热修复工程中,土壤热采样是判定地块内污染物残留量的重要手段.在热采样的土壤样品钻探、收集和冷却过程中,易发生土样中挥发性有机物(VOCs)或半挥发性有机物(SVOCs)损失,造成检测结果不能准确反映地块内污染物浓度.论文参照国内外热采样技术方法和应用案例,引入加标回收方法,选择适合的标准物质,在实验室内模拟现场热采样过程中,土样经收集和急冷2个步骤后,VOCs和SVOCs的回收程度.本次研究结合热修复工程常用加热温度数据,设计80℃和120℃2个温度环境.实验数据分析可得,SVOCs加标回收效果优于VOCs.本次试验结论和数据,可为热修复过程中热采样方法规范性、数据保真、过程控制等提供参考依据.

Soil sampling in in-situ thermal remediation process is an important way to determine the amount of pollutants reminded.During the sampling process,the loss of volatile organic compounds(VOCs)or semi-volatile organic compounds(SVOCs)in soil samples is prone to occur when drilling,collecting and cooling,which might cause the results not accurately reflect the concentration of pollutants in site.This article refers to domestic and foreign thermal sampling methods and application cases,introduces labeling recovery methods,selects suitable reference substances,and simulates the field thermal sampling process in the laboratory to test the VOCs and SVOCs recovery rate after collecting and cooling steps.This study combines the heating temperature data commonly used in thermal remediation to design two temperature environments,80℃ and 120℃.The analysis of experimental data shows that the recovery effect of SVOCs is better than that of VOCs.The conclusions and data of this test can be served as reference for the standardization of thermal sampling methods,data fidelity,process control,etc.