摘要 |
<p>The present invention relates to methods for treating metallic waste contaminated by radionuclides, wherein one of said methods comprises deactivating the metallic waste in a liquid medium using an etching solution, a cleaning solution and water. The metallic waste is then melted in an induction furnace while adding refining fluxing agents thereto. The ingots are further submitted to a dosimetric control before solidifying the etching solution. The deactivation of the metallic waste in a liquid medium is first carried out using the etching solution that contains from 5 to 200 g/l of a strong acid and from 0.1 to 15 g/l of a sulphur-containing activator or corrosion inhibitor at a temperature of between 10 and 100 °C. The method further comprises applying the cleaning solution that contains from 2 to 100 g/l of a strong acid and from 1 to 20 g/l of an oxidant at a temperature of between 10 and 90 °C before carrying out the treatment using water. The metal ion concentration in the etching solution is monitored so that in case said concentration exceeds a predetermined value, a portion of said solution is removed for solidification while the corresponding portion of the remaining solution is strengthened using a strong acid. During the melting process, the content of refining fluxing agents relative to the metal is kept in a range of between 0.9 to 4 wt.%.</p> |