Recycling of solvent used in a solvent extraction of petroleum hydrocarbons contaminated soil

JOURNAL OF HAZARDOUS MATERIALS

卷:186

Article

Wu, Guozhong^1,3  Li, Xingang^1,2  Coulon, Frederic³  Li, Hong^1,2  Lian, Jingyan⁴  Sui, Hong^1,2 

[1] Tianjin Univ, Sch Chem Engn & Technol, Tianjin 300072, Peoples R China

[2] Natl Engn Res Ctr Distillat Technol, Tianjin 300072, Peoples R China

[3] Cranfield Univ, Ctr Resource Management & Efficiency, Sustainable Syst Dept, Sch Appl Sci, Cranfield MK43 0AL, Beds, England

[4] Tianjin Univ Technol, Sch Chem & Chem Engn, Tianjin 300191, Peoples R China

关键词: Solvent extraction;    TU-A solvent;    Water washing;    Orthogonal experiment;   

DOI  :  10.1016/j.jhazmat.2010.11.041

来源: Elsevier

【 摘 要 】

The application of water washing technology for recycling an organic composite solvent consisting of hexane and pentane (4:1; TU-A solvent) was investigated for extracting total petroleum hydrocarbons (TPH) from contaminated soil. The effects of water volume, water temperature, washing time and initial concentration of solvent were evaluated using orthogonal experiments followed by single factor experiments. Our results showed that the water volume was a statistically significant factor influencing greatly the water washing efficiency. Although less important, the other three factors have all increased the efficacy of water washing treatment. Based on a treatment of 20g of contaminated soil with a TPH concentration of 140 mg g(-1), optimal conditions were found to be at 40 degrees C, 100 mL water, 5 min washing time and 660 mg g(-1) solvent. Semi-continuous water extraction method showed that the concentration of the composite solvent TU-A was reduced below 15 mg g(-1) d.w. soil with a recovery extraction efficiency > 97%. This finding suggests that water washing is a promising technology for recycling solvent used in TPH extraction from contaminated soils. (c) 2010 Elsevier B.V. All rights reserved.

【 授权许可】

Free