Abstract: A washing treatment system for contaminated soil, including: a classifier that is configured to obtain a sand fraction having a particle size within a predetermined range and a fine-grained fraction having a particle size smaller than the predetermined range, from contaminated soil containing one or more contaminants selected from dioxins and agricultural chemicals; a detaching/washing unit that is configured to detach a contaminant particle containing the from a surface of the sand fraction; a removal unit that is configured to generate air bubbles in a presence of water containing a flotation chemical, allows the detached contaminant-bearing particles to attach to the air bubbles to form froth, and removes the froth to obtain a first slurry containing primary purified soil; and an up-flow washing unit that is provided downstream of the removal unit, and is configured to supply the first slurry into up-flow water to purify the primary purified soil.

Abstract: What is provided is a washing treatment system (1) for contaminated soil, including: a classifier (10) that is configured to obtain a sand fraction (S4) having a particle size within a predetermined range and a fine-grained fraction (S3) having a particle size smaller than the predetermined range, from contaminated soil (S0) containing one or more contaminants selected from dioxins and agricultural chemicals; a detaching/washing unit (20) that is configured to detach a contaminant particle containing the contaminant from a surface of the sand fraction (S4); a removal unit (30) that is configured to generate air bubbles in a presence of water containing a flotation chemical, allows the detached contaminant-bearing particles to attach to the air bubbles to form froth (F1), and removes the froth (F1) to obtain a first slurry (S6) containing primary purified soil; and an up-flow washing unit (40) that is provided downstream of the removal unit (30), and is configured to supply the first slurry (S6) into up-flow w