PROCESS FOR CEMENTING RADIOACTIVE WASTE AND PRODUCT OF CEMENTATION.

摘要

A process for cementing radioactive wastes into products which are adapted for land disposal and reduced in the leakage of radioactivity and the products of cementation are disclosed. In order to minimize the leakage or radioactivity through voids within the product, the fraction of fine (up to 1 mu m) voids are adjusted to 20 vol % or less. Such voids are obtained by properly selecting the water/cement ratio, setting time of a mixture of a solidifying agent with a waste, addition of an organic polymer, and the like. The CaO content of the cement is controlled to be in the range of 0.62 x alpha + 0.27 x beta to 1.87 x alpha + 2.20 x beta [wherein alpha is a silicon content (wt.%) in terms of SiO2 and beta is an aluminum content (wt.%) in terms of Al2O3] in order to prevent formation of a soluble component of Ca(OH)2 which otherwise would be leached to form voids.