APPARATUS AND METHOD OF RECOVERING OIL SEPARATED FROM CONTAMINATED SOIL

摘要

PROBLEM TO BE SOLVED: To reduce the contamination of equipments due to oil in a post stage by adding water to soil contaminated by oil to make slurry and efficiently removing oil portion in the upstream part of a classification process. SOLUTION: The contaminated soil on which oil is stuck is mixed with water and stirred to make the slurry and to strip oil from the soil. After the coarse grain part of the soil in the slurry is removed in a wet screen apparatus 5, the slurry falls down to a slurry storage tank 6 to produce bubbles containing the oil on the slurry in the slurry storage tank. The slurry in the slurry storage tank is stirred by a stirring apparatus 22 and the soil particles are taken out from the bottom of the slurry tank without settling and depositing and sent to the classification apparatus 9. On the other hand, the position of the bubble layer upper surface on the slurry is detected by a liquid level meter 24 and is controlled. The bubble layer is overflowed from a discharge part 6b of the slurry storage tank 6 and discharged by setting the position of the bubble layer upper surface to be higher than the discharge port 21. COPYRIGHT: (C)2003,JPO