老化石油污染土壤的清洗处理

以华北油田老化长达1年以上的石油污染土壤为研究对象,采用自行选配的清洗剂对该污染土壤进行了一次清洗和二次清洗处理.实验结果表明,一次清洗后,污染土壤样品的含油率从26.34%～29.90%降到6.34%～7.84%,洗油率达80.06%～81.06%;经二次清洗处理后,污染土壤样品的含油率从26.34%～29.90%降到4.05%～4.85%,洗油率达88.06%～88.19%.在一次清洗和二次清洗的基础上,通过模拟实验确定了洗油污水回用的最佳回用率为80%,最佳加药质量浓度为0.4 g/L,该条件下污水的最终产生量也较少.按照该参数对华北油田的石油污染土壤进行了清洗实验,洗油率达79.20%～80.51%.

Surfactant enhanced washing of aged oil-contaminated soil

Six surfactant washing agents were prepared and compared in one-step washing and two-step washing of two old oil-contaminated soil samples from Huabei Oilfield. After one-step washing, the oil contents of the two samples were reduced from 26.34%~29.90% to 6.34%~7.84%, and the two-step washing further reduce the oil contents to 4.05%~4.85%. To minimize the washing agent dose and dirty wash water generation, another series of washing tests were conducted by reusing a fraction of the wash water from washing a portion of the oil-contaminated soil to wash another portion of the soil. Reusing 80% of the wash water and combined with an additional dose of 0.4 g/L of the best washing agent, the water saving surfactant enhanced soil washing achieved an oil removal of 79.20%~80.51%, newly the same as achieved using a higher dose (0.5 g/L) solution of washing agent.