Apparatus and process for the remediation of contaminated soil

摘要

A process and apparatus for the remediation of soil is provided with a plug flow of soil and counter-current wash of water. The contaminant-containing soil with water is first treated to disengage the contaminant from the soil and form a liquid phase containing water and contaminant. The treated soil and liquid phase is continuously introduced into a wash zone at a first end of the wash zone, and the soil and the liquid phase are conveyed in successive and discrete portions through the wash zone between the first end of the wash zone and a second end of the wash zone to provide an essentially plug-flow of the soil through the wash zone. Wash water is introduced into the wash zone by continuously adding water to the discrete portions at the second end of the wash zone, and the wash water is conveyed through the wash zone between adjacent wash cells toward the first end counter to the plug flow conveyance of the soil and the liquid phase, such that contaminants in the liquid phase are removed from the liquid phase by the wash water. The soil and liquid phase with contaminants removed are continuously withdrawn from the wash zone as each discrete portion reaches the second end of the wash zone. The wash water containing removed contaminants is withdrawn from the discrete portions at the first end of the wash zone.