Immobilization of liquid organic radioactive waste in porous cement matrix

The purpose of this research is to develop a technique for the immobilization of liquid organic radioactive waste through impregnation of porous cement matrices to ensure high degree of end-compound filling with waste. The technique consists in the following. First of all, the prepared porous cement matrix is placed into a primary package. At the hardening age of not less than 28 days, i.e. when main cement hydration processes are over, the waste is pumped into the cement-matrix pore space through the feeding device pre-installed in the container, causing the matrix impregnation with the waste. Cement composition provides obtaining matrices with strength of up to 9 MPa and porosity of up to 70 %. Compressive strength of the matrix after impregnation does not lower. Properties of the final compound meet the regulated requirements. Waste immobilization in the matrix is reliable. The degree of the end-product filling with organic waste ranged 56-64 % by volume or 47-52 % by weight. The developed mathematical model makes it possible to predict optimal impregnation parameters and output of dosing equipment for immobilization of various types of organic waste. (authors)