METHOD AND DEVICE FOR CLEANING CONTAMINATED SOIL

摘要

PROBLEM TO BE SOLVED: To provide a method and device for cleaning of contaminated soil in its original position by a degradation effect of microorganisms. SOLUTION: A cleaning area 15 of the contaminated soil 12 is enclosed by cut-off walls 6 up to a prescribed ground surface height (h) from an underground hardly water permeable layer 4 and a well 7 arriving at the peak surface of the hardly water permeable layer 4 from the apex height of the cut-off walls 6 is disposed in the cleaning area 15. Cleaning water 16 in which the nutrient materials of the contaminant degradation bacterial is contained is injected into the contaminated soil 12 in the cleaning area 15 by the well 7 and is sprung from the contaminated soil 12 to the ground surface 1 to form a spring water layer 14. Contaminated oil 5 is floated on the water surface of the spring water layer 14 and is separated as floating oil 10. The cleaning water 16 of the cleaning area 15 is lifted by the well 7 after this separation and simultaneously the air is inhaled into the contaminated soil 12. The contaminants are degraded by the degradation bacteria in the presence of the inhaled air and the injected nutrient materials. The contaminated soil 12 in the cleaning area 15 is cleaned by iterating the process from the injection to the recovery.