典型石油污染土壤中PAHs污染特征分析

Analysis on PAHs Pollution Characteristics in Typical Petroleum Contaminated Soil

为探讨废弃井场中土壤PAHs污染状况,采取江汉油田废弃井场土壤样品,对16种PAHS的质量分数及组成特征和垂直分布特征进行研究。结果表明:分析样品中∑16PAHs质量分数范围0.0084~2.5956μg·g^(-1),146号采样点PAHs质量分数均大于147号采样点,PAHS组成多以2~3环为主,∑16PAHs和单体分布基本一致,其中土壤层位在0~20cm时,菲(Phe)、荧蒽(Flu)、屈(chr)占比较大,为主要污染物;147号采样点,PAHs多以5~6环为主,屈(Chry)、苯并(b)荧蒽(BbF)占比较大,土壤∑16PAHs和单体质量分数随深度增加而减小。通过单组分比值(Ant/(Ant+Phe))的分析得出,146号采样点土壤中PAHs多为石油源,而147号采样点土壤中的PAHs多为燃烧源,且Fla/(Fla+Pyr)比值大于0.5,说明来源于煤、植物、木炭燃烧。

To explore the soil PAHs pollution status in abandoned wellsites,soil samples from abandoned wellsites in Jianghan oilfield were used as research objet,composition and vertical distribution characteristics of 16 PAHs were analyzed.The results showed that the mass fraction of ∑16 PAHs in the analyzed samples ranged from 0.0084μg·g^(-1) to 2.5956μg·g^(-1),and the PAHs mass fraction of sampling point 146 was greater than that of sampling point 147.The composition of PAHs was mainly 2~3 rings,and the distribution of ∑16 PAHs and monomers were basically the same.Where the soil layer was at 0~20 cm,phenanthrene(Phe),fluoranthene(Flu),flex(chr)accounted for a relatively large amount and were the main pollutants;in sampling point 147,PAHs was mostly 5~6 ring chrysanthemum(Chry),benzo(b)fluoranthene(BbF)accounted for a large proportion,soil ∑16 PAHs and monomer mass fraction decreased with increasing depth.Through the analysis of the single component ratio(Ant/(Ant+Phe)),it was concluded that the PAHs in the soil at sampling point 146 was mostly a petroleum source,and the PAHs in the soil at sampling point 147 was mostly a combustion source,and Fla/(Fla+Pyr)ratio was greater than 0.5,indicating that it was derived from the combustion of coal,plants and charcoal.