石油类污染物在土柱中迁移过程分异规律研究

Study on the Differentiation Law of Migration Process of Petroleum Pollutants in Homogeneous Soil Column

厘清石油类污染物在土壤中的迁移、富集规律,将有助于对石油污染土壤的治理恢复。利用大庆油田六厂附近未污染的土壤作为均质土柱填充物,通过模拟淋滤实验研究石油类污染物在均质土柱中迁移过程的分异规律。对不同深度土壤样品进行有机污染物超声萃取及柱层析色谱分离。结果表明:淋滤实验对芳香烃影响较大,深度越深,相对质量分数越高,最高约为41.0%;非烃不易受淋滤实验影响,最低约为4.0%;饱和烃和沥青质在土柱中的质量分数相对稳定。不同深度土壤样品污染物气相色谱实验表明:浅层土样所含烃类主要是C12~C26,C17、C18和C19相对质量分数较高。由于深度的增加,C17以上低碳组分峰高逐渐减小。当污染物质量分数相对无变化时,土柱中的烃类污染物主要成分为C17~C21。可见,芳香烃在土壤中的迁移能力最强,高碳数的C17~C21化合物是深层土壤中主要的烃类污染物。

Clarifying the law of migration and enrichment of petroleum pollutants in the soil will help the restoration of oil-contaminated soil.In this paper,the uncontaminated soil near the No.6 plant of Daqing oilfield company was used as homogeneous soil column filler,and the simulation of the leaching experiment of petroleum contaminants in the migration process of the homogeneous soil column was carried out through simulated leaching experiments.Ultrasonic extraction of organic pollutants and column chromatography separation were carried out on soil samples of different depths.The results showed that the leaching experiment had great impact on aromatic hydrocarbons,the deeper the depth,the higher the relative content,the highest was about 41.0%,the non-hydrocarbon was not easily affected by the leaching experiment,the lowest was about 4.0%,saturated hydrocarbons and asphaltenes in the soil column were relatively stable.Gas chromatography experiments of pollutants from soil samples at different depths showed that the shallow soil samples contained mainly hydrocarbons between C12 and C26,and the relative contents of C17,C18 and C19 were relatively high.As the depth increased,the peak height of low carbon components above C17 gradually decreased.When the content of pollutants was relatively unchanged,the main components of hydrocarbon pollutants in the soil column were C17~C21.It was seen that aromatic hydrocarbons had the strongest migration ability in soil,and high carbon number C17~C21 compounds were the main hydrocarbon pollutants in deep soil.