| 摘要 |
<p>The invention relates to a process for the decontamination of a radioactively-polluted soil, e.g. uranium-infested as a consequence of the activities of exploitation of a radioactive deposit, of ore processing and uranium transportation to the user. According to the invention, the process consists in dismantling, under radiometric control, the contaminated area, with an alkaline uranium solution, screening the contaminated soil with a 2.5 mm-mesh sieve, decontaminating the soil fraction +2.5 mm by washing with water, chemically decontaminating the soil fraction -2.5 mm, under the influence of ultrasounds, separating the uranium denuded from the soil, by filtration separation of the residual solution of the decontamination reagent, washing and filtering the soil pulp from the previous filtration twice, using the decontaminated soil sample to the ecological reconstruction of the contaminated area, recuperative separation of uranium from the uranium-bearing solutions, by ion exchange. The uranium accidentally-contaminated soil is dismantled under radiometric control, the limit of separation between the uranium-contaminated and the uncontaminated soil being the flow rate of the doseγof 0.30μSv/h, flow rate which corresponds to a uranium content in the soil of 0.0040%, admitted by NMR-01, the dismantled soil being separated into two fractions, using a 2.5 mm-mesh sieve.</p> |
