油田区土壤石油污染特性及理化性质关系

Contamination characteristics and its relationship with physicochemical properties of oil polluted soils in oilfields of China

基于不同区域环境下油田区石油污染土壤的调查取样,对土壤的石油污染特性及其与理化性质的关系进行探讨,为油田区污染土壤生物修复提供非生物学依据。结果表明,油田区土壤受到了不同程度的石油污染,含油率最高达23%,超过环境背景值的500～1000倍。土壤石油组分中烷烃、芳烃等轻质组分占总量的50%以上,可为生物修复或与其他修复措施的联合开展提供可靠的物质基础。土壤含油率与含水率存在制约关系,当含油率超过8%时,土壤含水率普遍低于5%。石油污染土壤有机质含量与含油率呈正相关关系,当土壤含油率超过7%时,土壤有机质含量普遍高于10%。调查油田区的土壤质地以粉壤土和砂土为主,占油田土样总数的65%,可为生物修复提供较好的土壤条件。

The contamination characteristics of oil polluted soils were analyzed by investigating and sampling in different oilfields of China, and its relationship with the physicochemical properties was investigated in detail in this research. Oil contents and component analysis indicated that the soils in oilfields of China were polluted by petroleum universally, with the highest oil content reaching 23%, which was 500-1000 times as much as the background value of oil in unpolluted samples. The light components, including alkanes and aromatic compounds accounted for more than 50% of the total hydrocarbon, and were readily degraded by bacteria and improved the degrading microbe activities than the heavy oil components. The water contents of soils in oilfields decreased to below 5% mostly when oil contents were higher than 8%, which indicated that the water contents were restricted by crude oil in contaminated soils in different oilfields. The organic matter contents of soils were in positive correlation with oil contents, there fore the organic matter contents increased to above 10% when oil contents were higher than 70//oo. The major soil texture of the investigated oilfields was fine doras and sandy clay （65% of the total soil samples）, which could provide suitable soil condition for the bioremediation of oil contaminated soils in oilfields of China.