Engineering Application In Remediation Of Petroleum Contaminated Site By Soil Vapor Extraction

Soil was the main natural resource for human survival. With the rapid development of petroleum industry and the wide use of petroleum products, petroleum contaminated soils widespread and serious all over the world. Petroleum pollutants especially the typical representatives of BTEX and PAHs often made much risk to human health and ecological safety which were high volatility and toxicity. Soil vapor extraction was the most widely used in these sites, included in-situ and ex-situ. The research in our country for it was concentrated in the stage of theoretical research and laboratory simulation. This study conducted a 2700 m3-scale production test to research the actual remediation process of petroleum contaminated soil. Studied on the removal efficiency of benzene in soil. Then, explored the change of soil physical and chemical properties. Finally, Discussed its influence on the removal efficiency of benzene in soil.1. Established some test methods which were suitable for this study: benzene in soil (GC-FID), pH, organic matter content, water content and so on.2. The productive test ran for 99 days. The concentrations of benzene in soil from all the 18 sampling areas reduced to 0.03～0.32 mg/kg at the end. The average concentration was 0.17 mg/kg and the average removal rate reached 98%. All the concentrations of the samples were under the target remediation value (0.64 mg/kg).3. The sample analysis data belonged to normal distribution, the fitting results of benzene removal indicated that their half-life were about 10 days.4. During the test, pH was in the range of 8.6～10.2, soil organic matter was between 0.889% and 3.070%, water content was in the range of 19.39%～34.13%. The average water content in upper layer (0.8m,24.39%) was slightly lower than in the lower layer (2.0m,26.74%). Increased of soil organic matter or water content would slow down the removal trend of benzene in soil.