MELTING AND GRANULATING OF CONTAMINATED STEEL SCRAP

Increasing quantities of radioactively contaminated and activated metallic residues can be expected to be treated and disposed off due to decommissioning of nuclear installations and site remediation. In view of the high disposal costs and the anticipated long intermediate storage time maximum volume reduction of radioactive waste is one of the key-notes. For more than 10 years Siempelkamp's CARLA melting plant in Krefeld has successfully demonstrated the recycling of slightly radioactively contaminated scrap. Re-use has been represented by manufacture of high-quality waste containers and shielding equipment made of ductile cast iron. In the last few years a supplementary recycling path has been developed in order to involve the potential of scrap with high chromium and/or nickel content. The process is based on a special granulating technique and the substitution of the hematite (iron ore) portion of heavy concrete shieldings. For official attestation of the granule concrete shieldings all necessary tests for type A/IP II container approval have been successfully performed according to the IAEA requirements. Furthermore, different versions of such containers have been qualified for their usage in German repositories