Process and device for conditioning low and middle level radioactive waste solutions with hydraulic binders.

摘要

1. A process for encapsulating low- and medium-level radio-active waste containing borates, by hydraulic cements, by chemical treatment with a view to the preparation of crystals of tetrahydrated calcium borate, reduction in volume and mixing of the product obtained with at least one hydraulic cement, characterized in that : - said tetrahydrated calcium borate is produced by adding to the solution to be treated a quantity of lime calculated so as to form the borate B2 O3 CaO ; - the operation of volume reduction is carried out by evaporation, under reduced pressure, of the solutions and/or suspensions, said reduced pressure being between about 0.1 and 0.3-10**5 Pa bar and applied after the phase of preparation of the crystals of tetrahydrated calcium borate ; - and in that said volume reduction is continued until a concretable suspension is obtained at the end of the process, which contains from about 30 to about 70% of dry matter.