Preparation method of borosilicate glass ceramic solidified body containing uranpyrochlore

A borosilicate glass and ceramic solidification technology, which is applied in the field of radioactive waste treatment, can solve the problems of limited containment capacity, limited proportion of ceramic phase, and the inability of the solidified body to handle high-level radioactive waste to the greatest extent, so as to increase the containment capacity, The effect of uniform distribution of ceramic phase and compact structure

CN109761500AInactive Publication Date: 2019-05-17SOUTHWEAT UNIV OF SCI & TECH
8 Cites 3 Cited by

Patent Information

Authority / Receiving Office
CN · China
Patent Type
Applications(China)
Current Assignee / Owner
Publication Date
2019-05-17
Estimated Expiration
Not applicable · inactive patent

Smart Images

  • Figure 1
    Figure 1
  • Figure 2
    Figure 2
  • Figure 3
    Figure 3
Patent Text Reader

Abstract

The invention relates to the technical field of radioactive waste treatment, in particular to a preparation method of a borosilicate glass ceramic solidified body containing uranpyrochlore. The preparation method comprises the following steps of respectively performing wet mixing drying and pre-sintering, gradual melting, sintering and quenching with SiO2, Al2O3, Na2CO3, B2O3, CaF2, CaO, U3O8 andTiO2 as raw materials to prepare the borosilicate glass ceramic solidified body. The preparation method has the advantages that the crystallization rate of the uranpyrochlore in glass can be regulatedand controlled; the ingredients remained by nuclide in the glass phase can be reduced; the accommodating capacity of nuclide U in the ceramic phase can be improved; the accommodating capacity of thenuclide U in the whole solidified body can be improved; the prepared borosilicate glass ceramic solidified body containing uranpyrochlore has the advantages of uniform crystal grain distribution, hightissue compactness and high intensity.
Need to check novelty before this filing date? Find Prior Art

Description

technical field

[0001] The invention relates to the technical field of radioactive waste treatment, in particular to a method for preparing a solidified body of borosilicate glass ceramics containing uranium pyrochlore. Background technique

[0002] In the reprocessing process of spent fuel with co-decontamination of uranium and plutonium, high-level radioactive wastes (High-Level Radioactive Wastes, HLWs) will be produced. HLWs are highly radioactive, highly toxic, and have a high heating rate. If HLWs are released into the environment, it will Great harm to the environment.

[0003] In the prior art, there are ways to vitrify HLLW (high-level radioactive waste) or to solidify HLLW ceramics to process HLLW, but HLLW vitrification has low containment capacity for actinide nuclides (≤0.4wt.%) and poor long-term stability (Easy phase separation and water-soluble yellow phase) and other problems, resulting in the development of large-scale production of HLLW vitrification; HLL...

Examples

Embodiment 1

[0035] A method for preparing a borosilicate glass ceramic solidified body containing uranium pyrochlore in this embodiment, step 1, weighing the following components by weight percentage: SiO 2 20.5%, Al 2 o 3 4%, Na 2 CO 3 9%, B 2 o 3 4%, CaF 2 17.5%, CaO4%, U 3 o 8 25.5%, TiO 2 15%;

[0036] Step 2. Pretreatment of glass-ceramic raw materials

[0037] SiO 2 、Al2 o 3 、Na 2 CO 3 , B 2 o 3 , CaF 2 Wet-mix and dry the six components of CaO to obtain a uniformly mixed first mixture, and U 3 o 8 and TiO 2 The two components were wet-mixed and dried to obtain a uniformly mixed second mixture. The first mixture and the second mixture were respectively sintered at 650° C. for 1 h under an argon atmosphere, and then the sintered first mixture and The second mixture is ball milled for 3 hours respectively, the first mixture after ball milling is the first glass-ceramic raw material, and the second mixture after ball-milling is the second glass-ceramic raw material...

Embodiment 2

[0048] A method for preparing a borosilicate glass ceramic solidified body containing uranium pyrochlore in this embodiment, step 1, weighing the following components by weight percentage: SiO 2 20%, Al 2 o 3 2%, Na 2 CO 3 8%, B 2 o 3 3%, CaF 2 17%, CaO3%, U 3 o 8 30%, TiO 2 16%;

[0049] Step 2. Pretreatment of glass-ceramic raw materials

[0050] SiO 2 、Al 2 o 3 、Na 2 CO 3 , B 2 o 3 , CaF 2 Wet-mix and dry the six components of CaO to obtain a uniformly mixed first mixture, and U 3 o 8 and TiO 2 The two components were wet mixed and dried to obtain a uniformly mixed second mixture. The first mixture and the second mixture were respectively sintered at 750° C. for 3 hours under an argon atmosphere, and then the sintered first mixture and The second mixture is ball milled for 4 hours respectively, the first mixture after ball milling is the first glass-ceramic raw material, and the second mixture after ball-milling is the second glass-ceramic raw material...

Embodiment 3

[0066] A method for preparing a borosilicate glass ceramic solidified body containing uranium pyrochlore in this embodiment, step 1, weighing the following components by weight percentage: SiO 2 23.5%, Al 2 o 3 2.1%, Na 2 CO 3 8.1%, B 2 o 3 3.1%, CaF 2 20%, CaO3.1%, U 3 o 8 20.1%, TiO 2 20%;

[0067] Step 2. Pretreatment of glass-ceramic raw materials

[0068] SiO 2 、Al 2 o 3 、Na 2 CO 3 , B 2 o 3 , CaF 2 Wet-mix and dry the six components of CaO to obtain a uniformly mixed first mixture, and U 3 o 8 and TiO 2 The two components were wet-mixed and dried to obtain a uniformly mixed second mixture. The first mixture and the second mixture were respectively sintered at 700° C. for 2 hours under an argon atmosphere, and then the sintered first mixture and The second mixture is ball milled for 3.5 hours respectively, the first mixture after ball milling is the first glass-ceramic raw material, and the second mixture after ball-milling is the second glass-cerami...