Solidified body used for performing glass curing process on low-medium radioactive waste and method

Abstract

The invention provides a preparation method of a solidified body used for performing glass curing process on a low-medium radioactive waste. The method comprises the following steps: taking the components SiO2, H3BO3, Na2CO3 and CaO as the raw materials, compounding and mixing, melting for 2.5-3 hours at the temperature of 1250 DEG C, after that, pouring the materials to a mold which is pre-heated to be 500 DEG C and molding, keeping the temperature at 500 DEG C for 0.5-1 hour, and then reducing the temperature to be room temperature at a rate of temperature fall of 0.5-1 DEG C/min, then the product can be prepared. The solidified body prepared by the invention can be used for performing glass curing process on the low-medium radioactive waste, realizing the volume reduction maximization of the solidified radioactive waste, more conforming to the value pursuit of waste minimization in radioactive waste treatment, and realizing the inorganization and stabilization of the solidified waste.

Description

technical field [0001] The invention relates to the technical field of nuclear power plant low- and medium-level radioactive waste treatment, in particular to a solidified body and method for vitrification treatment of low- and medium-level radioactive waste. Background technique [0002] The development and utilization of nuclear energy has brought huge economic and social benefits to human beings, but at the same time produced a large amount of radioactive waste, which has brought a greater threat to the living environment of human beings. Therefore, how to safely and effectively dispose of radioactive waste to maximize its isolation from the biosphere has become an increasingly urgent and important issue facing the nuclear industry and nuclear science, and is a key factor affecting the sustainable and healthy development of nuclear energy. [0003] For the disposal of radioactive waste, people think that the most reasonable measure is to solidify the radioactive waste fir...

AI Technical Summary

Problems solved by technology

Among them, ceramic solidification has a large containment capacity for radioactive elements in low- and intermediate-level radioactive waste, and crystals have strong thermal stability relative to glass, but ceramic solidification has strong selectivity for radioactive elements, and most of the non-radioactive waste in waste has no effect on ceramic solidification. It is very large; glass-ceramic solidification can effectively solve the problems of ceramic solidification. Most of the radioactive elements are solidified in the lattice, and non-radioactive waste and a small amount of elements that are not solidified in the lattice are solidified in the outer glass matrix, but The heat treatment process of this solidification method is relatively complicated and is still in the research stage; although the geological stability, chemical stability, thermal stability and radiation resistance of the solidified body are good in the artificial rock solidification treatment, the solidification process is complicated, and it is not compatible with the solidification process. Wastes such as high-concentration sodium salts have poor compatibility, and have strong selectivity for elements in low-intermediate radioactive wastes. The technical requirements are very high. At present, they are still in the stage of laboratory theoretical research, and the equipment used is complicated and expensive. The consumption of materials and energy in the process of treatment is very large; vitrification means that the nuclear waste liquid is concentrated and evaporated to dryness, mixed with mineral powder materials with appropriate composition, sintered at high temperature into a glass solid, and then stored in a special storage area in a sealed manner , this method has the advantages of high strength, good compactness and stable structure of the solidified body, and the leaching rate of the solidified radionuclide is very low when soaked in water, so it has high safety. It has become a relatively mature technology in Europe, America, Japan and other countries. However, the solidified waste body is either too large in size and weight and too expensive, or has a low degree of fit, cannot change the chemical form of the solidified waste body, and has poor radiation stability and thermal stability.

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