Behaviors of Aqueous Oil Adsorption-release in Oil-contaminated Soils

摘要

On the basis of the investigation of oil contamination of soil-water-plant systems in the Shen(yang)fu(shun) irrigation field, upper soils and bottom soils are sampled along 3 representative soil profiles, and their major physico-chemical properties are analyzed. In addition, dynamic curves and isotherms of aqueous oil adsorption on soils have been measured. At last, release behaviors of aqueous oil are analyzed by means of Darcy's setting. The studies show the equilibrium period of the adsorption is 20-24 h, and all the adsorption isotherms are linear. It is found some oil may be released from the contaminated soils when the aqueous oil concentrations are lower than certain values. In addition, the release ratios of soils L2-1, Sl-1 and Xl-1 are 0.86%, 0.73% and 1.30% respectively according to 983 h leaching tests, which means only small amount of aqueous oil can be released from the on-contaminated soils and the release is a very slow process.