METHODS OF PREPARING MATRIX FOR VITRIFICATION OF RADIOACTIVE WASTE AND GLASS WASTEFORM

Abstract

Disclosed herein is a method for preparing a matrix for vitrifying radioactive waste, including: grinding natural magmatic rocks; and melting the ground product at 1450-1500 C. for 3-4.5 h followed by moulding and annealing to produce the matrix. The matrix includes 45%-65% by weight of SiO.sub.2, 9%-18% by weight of Al.sub.2O.sub.3, 4%-12% by weight of CaO, 3%-10% by weight of MgO, 6%-16% by weight of Fe.sub.2O.sub.3+FeO, 2%-9% by weight of Na.sub.2O+K.sub.2O and 1%-5% by weight of TiO.sub.2. The matrix is doped with simulated radioactive waste, ground, melted, moulded and annealed to obtain a glass wasteform with good chemical and thermal stability.

Claims

1. A method for preparing a matrix for vitrification of radioactive waste, comprising: (1) grinding a natural magmatic rock; (2) melting the ground natural magmatic rock at 1450-1500 C. for 3-4.5 h; (3) moulding the melted product in a mold preheated to 700-850 C.; and (4) keeping the moulded product at 600-700 C. for 1-2 h followed by cooling to room temperature at a rate of 1-2 C./min to prepare the matrix for the vitrification of the radioactive waste.

2. The method of claim 1, wherein the matrix obtained in step (4) comprises 45%-65% by weight of SiO.sub.2, 9%-18% by weight of Al.sub.2O.sub.3, 4%-12% by weight of CaO, 3%-10% by weight of MgO, 6%-16% by weight of Fe.sub.2O.sub.3+FeO, 2%-9% by weight of Na.sub.2O+K.sub.2O and 1%-5% by weight of TiO.sub.2.

3. The method of claim 2, wherein the matrix obtained in step (4) comprises 49.70% by weight of SiO.sub.2, 14.83% by weight of Al.sub.2O.sub.3, 8.76% by weight of CaO, 4.27% by weight of MgO, 10.52% by weight of Fe.sub.2O.sub.3+FeO, 4.78% by weight of Na.sub.2O, 1.99% by weight of K.sub.2O and 3.16% by weight of TiO.sub.2.

4. The method of claim 2, wherein the matrix obtained in step (4) comprises 47.73% by weight of SiO.sub.2, 14.22% by weight of Al.sub.2O.sub.3, 9.29% by weight of CaO, 4.81% by weight of MgO, 13.01% by weight of Fe.sub.2O.sub.3+FeO, 2.19% by weight of Na.sub.2O, 1.48% by weight of K.sub.2O and 3.37% by weight of TiO.sub.2.

5. A method for preparing a glass wasteform of radioactive waste, comprising: (1) grinding and mixing 93%-99% by weight of the matrix of claim 1 with 1%-7% by weight of simulated radioactive waste to produce a mixture; wherein the simulated radioactive waste is MoO.sub.3 or Nd.sub.2O.sub.3; (2) melting the mixture at 1100-1300 C. for 3-4.5 h; (3) moulding the melted product in a mold preheated to 700-850 C.; and (4) keeping the moulded product at 600-700 C. for 1-2 h followed by cooling to room temperature at a rate of 1-2 C./min to prepare the glass wasteform of radioactive waste.

6. The method of claim 5, wherein the grinding in step (1) is crushing by a jaw crusher and then milling by a ball mill.

7. The method of claim 5, wherein in step (1), 93%-95% by weight of the matrix and 1%-5% by weight of the simulated radioactive waste are mixed; and the simulated radioactive waste is MoO.sub.3.

8. The method of claim 5, wherein in step (1), the matrix comprises 45%-65% by weight of SiO.sub.2, 9%-18% by weight of Al.sub.2O.sub.3, 4%-12% by weight of CaO, 3%-10% by weight of MgO, 6%-16% by weight of Fe.sub.2O.sub.3+FeO, 2%-9% by weight of Na.sub.2O+K.sub.2O and 1%-5% by weight of TiO.sub.2.

9. The method of claim 6, wherein in step (1), the matrix comprises 45%-65% by weight of SiO.sub.2, 9%-18% by weight of Al.sub.2O.sub.3, 4%-12% by weight of CaO, 3%-10% by weight of MgO, 6%-16% by weight of Fe.sub.2O.sub.3+FeO, 2%-9% by weight of Na.sub.2O+K.sub.2O and 1%-5% by weight of TiO.sub.2.

10. The method of claim 7, wherein in step (1), the matrix comprises 45%-65% by weight of SiO.sub.2, 9%-18% by weight of Al.sub.2O.sub.3, 4%-12% by weight of CaO, 3%-10% by weight of MgO, 6%-16% by weight of Fe.sub.2O.sub.3+FeO, 2%-9% by weight of Na.sub.2O+K.sub.2O and 1%-5% by weight of TiO.sub.2.

11. The method of claim 5, wherein in step (1), the matrix comprises 49.70% by weight of SiO.sub.2, 14.83% by weight of Al.sub.2O.sub.3, 8.76% by weight of CaO, 4.27% by weight of MgO, 10.52% by weight of Fe.sub.2O.sub.3+FeO, 4.78% by weight of Na.sub.2O, 1.99% by weight of K.sub.2O and 3.16% by weight of TiO.sub.2.

12. The method of claim 6, wherein in step (1), the matrix comprises 49.70% by weight of SiO.sub.2, 14.83% by weight of Al.sub.2O.sub.3, 8.76% by weight of CaO, 4.27% by weight of MgO, 10.52% by weight of Fe.sub.2O.sub.3+FeO, 4.78% by weight of Na.sub.2O, 1.99% by weight of K.sub.2O and 3.16% by weight of TiO.sub.2.

13. The method of claim 7, wherein in step (1), the matrix comprises49.70% by weight of SiO.sub.2, 14.83% by weight of Al.sub.2O.sub.3, 8.76% by weight of CaO, 4.27% by weight of MgO, 10.52% by weight of Fe.sub.2O.sub.3+FeO, 4.78% by weight of Na.sub.2O, 1.99% by weight of K.sub.2O and 3.16% by weight of TiO.sub.2 and 1.99%.

14. The method of claim 5, wherein in step (1), the matrix comprises 47.73% by weight of SiO.sub.2, 14.22% by weight of Al.sub.2O.sub.3, 9.29% by weight of CaO, 4.81% by weight of MgO, 13.01% by weight of Fe.sub.2O.sub.3+FeO, 2.19% by weight of Na.sub.2O, 1.48% by weight of K.sub.2O and 3.37% by weight of TiO.sub.2 and 3.90%.

15. The method of claim 6, wherein in step (1), the matrix comprises 47.73% by weight of SiO.sub.2, 14.22% by weight of Al.sub.2O.sub.3, 9.29% by weight of CaO, 4.81% by weight of MgO, 13.01% by weight of Fe.sub.2O.sub.3+FeO, 2.19% by weight of Na.sub.2O, 1.48% by weight of K.sub.2O and 3.37% by weight of TiO.sub.2.

16. The method of claim 7, wherein in step (1), the matrix comprises 47.73% by weight of SiO.sub.2, 14.22% by weight of Al.sub.2O.sub.3, 9.29% by weight of CaO, 4.81% by weight of MgO, 13.01% by weight of Fe.sub.2O.sub.3+FeO, 2.19% by weight of Na.sub.2O, 1.48% by weight of K.sub.2O and 3.37% by weight of TiO.sub.2.

Description

DETAILED DESCRIPTION OF EMBODIMENTS

[0034] The embodiments below are intended to further describe this invention, but are not intended to limit the scope of the invention. Any modifications and adjustments made by those skilled in the art based on the disclosure of the invention shall fall within the scope of the invention.

EXAMPLE 1

[0035] A method for preparing a matrix for vitrifying radioactive waste was provided herein, which was specifically described as follows.

[0036] (1) Grinding

[0037] Natural magmatic rocks were used as raw materials and ground (specifically crushed by a jaw crusher and milled by a ball mill).

[0038] (2) Melting

[0039] The ground product was heated and melted at 1480 C. for 3.5 h.

[0040] (3) Moulding

[0041] The melted product was moulded in a mold preheated to 800 C.

[0042] (4) Annealing

[0043] The moulded product was kept at 600 C. for 1 h and cooled to room temperature at a rate of 1 C./min to produce the matrix for vitrifying radioactive waste.

[0044] The matrix obtained in step (4) included 49.70% by weight of SiO.sub.2, 14.83% by weight of Al.sub.2O.sub.3, 8.76% by weight of CaO, 4.27% by weight of MgO, 10.52% by weight of Fe.sub.2O.sub.3+FeO, 4.78% by weight of Na.sub.2O, 1.99% by weight of K.sub.2O and 3.16% by weight of TiO.sub.2, where the matrix further included 1.99% by weight of at least five compounds selected from the group consisting of MnO, P.sub.2O.sub.5, SO.sub.3, BaO, SrO, ZrO.sub.2, CuO, ZnO, Nb.sub.2O.sub.5, Rb.sub.2O and Y.sub.2O.sub.3.

EXAMPLE 2

[0045] A method for preparing a matrix for vitrifying radioactive waste was provided herein, which was specifically described as follows.

[0046] (1) Grinding

[0047] Natural magmatic rocks were used as raw materials and ground (specifically crushed by a jaw crusher and milled by a ball mill).

[0048] (2) Melting

[0049] The ground product was heated and melted at 1450 C. for 3-3.5 h.

[0050] (3) Moulding

[0051] The melted product was moulded in a mold preheated to 800 C.

[0052] (4) Annealing

[0053] The moulded product was kept at 600 C. for 1 h and cooled to room temperature at a rate of 1 C./min to produce the matrix for vitrifying radioactive waste.

[0054] The matrix obtained in step (4) included 47.73% by weight of SiO.sub.2, 14.22% by weight of Al.sub.2O.sub.3, 9.29% by weight of CaO, 4.81% by weight of MgO, 13.01% by weight of Fe.sub.2O.sub.3+FeO, 2.19% by weight of Na.sub.2O, 1.48% by weight of K.sub.2O and 3.37% by weight of TiO.sub.2, where the matrix further included 3.90% by weight of at least five compounds selected from the group consisting of MnO, P.sub.2O.sub.5, SO.sub.3, BaO, SrO, ZrO.sub.2, CuO, ZnO, Nb.sub.2O.sub.5, Rb.sub.2O and Y.sub.2O.sub.3.

EXAMPLE 3

[0055] A method for preparing a glass wasteform of radioactive waste was provided herein, which was specifically described as follows.

[0056] (1) Grinding and Mixing

[0057] 28.5 g of the matrix of Example 1 and 1.5 g of MoO.sub.3 as simulated radioactive waste were ground and mixed to produce a mixture, where the matrix used herein included 49.70% by weight of SiO.sub.2, 14.83% by weight of Al.sub.2O.sub.3, 8.76% by weight of CaO, 4.27% by weight of MgO, 10.52% by weight of Fe.sub.2O.sub.3+FeO, 4.78% by weight of Na.sub.2O, 1.99% by weight of K.sub.2O and 3.16% by weight of TiO.sub.2, where the matrix further included 1.99% by weight of at least five compounds selected from the group consisting of MnO, P.sub.2O.sub.5, SO.sub.3, BaO, SrO, ZrO.sub.2, CuO, ZnO, Nb.sub.2O.sub.5, Rb.sub.2O and Y.sub.2O.sub.3, and the grinding was performed by a ball mill, and the mixture had a particle size less than 200 mesh.

[0058] (2) Melting

[0059] The mixture was heated and melted at 1250 C. for 3 h.

[0060] (3) Moulding

[0061] The melted product was moulded in a mold preheated to 800 C.

[0062] (4) Annealing

[0063] The moulded product was kept at 600 C. for 1 h and cooled to room temperature at a rate of 1 C./min to produce the glass wasteform of MoO.sub.3 radioactive waste.

[0064] The glass wasteform of MoO.sub.3 radioactive waste prepared herein was immersed in deionized water at 90 C. for 28 days, where the weight loss rate of element Mo was less than 210.sup.5 g.Math.m.sup.2.Math.d.sup.1.

EXAMPLE 4

[0065] A method for preparing a glass wasteform of radioactive waste was provided herein, which was specifically described as follows.

[0066] (1) Grinding and Mixing

[0067] 28.5 g of the matrix of Example 2 and 1.5 g of Nd.sub.2O.sub.3 as simulated radioactive waste were ground and mixed to produce a mixture, where the matrix used herein included 47.73% by weight of SiO.sub.2, 14.22% by weight of Al.sub.2O.sub.3, 9.29% by weight of CaO, 4.81% by weight of MgO, 13.01% by weight of Fe.sub.2O.sub.3+FeO, 2.19% by weight of Na.sub.2O, 1.48% by weight of K.sub.2O and 3.37% by weight of TiO.sub.2, where the matrix further included 3.90% by weight of at least five compounds selected from the group consisting of MnO, P.sub.2O.sub.5, SO.sub.3, BaO, SrO, ZrO.sub.2, CuO, ZnO, Nb.sub.2O.sub.5, Rb.sub.2O and Y.sub.2O.sub.3, and the grinding was performed by a ball mill, and the mixture had a particle size less than 200 mesh.

[0068] (2) Melting

[0069] The mixture was heated and melted at 1200 C. for 3 h.

[0070] (3) Moulding

[0071] The melted product was moulded in a mold preheated to 800 C.; and

[0072] (4) Annealing

[0073] The moulded product was kept at 600 C. for 1 h and cooled to room temperature at a rate of 1 C./min to produce the glass wasteform of Nd.sub.2O.sub.3 radioactive waste.

[0074] The glass wasteform of Nd.sub.2O.sub.3 radioactive waste prepared herein was immersed in deionized water at 90 C. for 28 days, where the weight loss rate of element Nd was less than 510.sup.6 g.Math.m.sup.2.Math.d.sup.1.

EXAMPLE 5

[0075] A method for preparing a matrix for vitrifying radioactive waste was provided herein, which was specifically described as follows.

[0076] (1) Grinding

[0077] Natural magmatic rocks were used as raw materials and ground.

[0078] (2) Melting

[0079] The ground product was heated and melted at 1480 C. for 4 h.

[0080] (3) Moulding

[0081] The melted product was moulded in a mold preheated to 780 C.

[0082] (4) Annealing

[0083] The moulded product was kept at 650 C. for 1.5 h and cooled to room temperature at a rate of 1.5 C./min to produce the matrix for vitrifying radioactive waste.

[0084] The matrix obtained in step (4) included 51.89% by weight of SiO.sub.2, 13.56% by weight of Al.sub.2O.sub.3, 7.78% by weight of CaO, 6.54% by weight of MgO, 10.78% by weight of Fe.sub.2O.sub.3+FeO, 4.89% by weight of Na.sub.2O+K.sub.2O and 2.28% by weight of TiO.sub.2, where the matrix further included 2.28% by weight of at least five compounds selected from the group consisting of MnO, P.sub.2O.sub.5, SO.sub.3, BaO, SrO, ZrO.sub.2, CuO, ZnO, Nb.sub.2O.sub.5, Rb.sub.2O and Y.sub.2O.sub.3.

EXAMPLE 6

[0085] A method for preparing a matrix for vitrifying radioactive waste was provided herein, which was specifically described as follows.

[0086] (1) Grinding

[0087] Natural magmatic rocks were used as raw materials and ground.

[0088] (2) Melting

[0089] The ground product was heated and melted at 1450 C. for 4.5 h.

[0090] (3) Moulding

[0091] The melted product was moulded in a mold preheated to 700 C.

[0092] (4) Annealing

[0093] The moulded product was kept at 600 C. for 2 h and cooled to room temperature at a rate of 1 C./min to produce the matrix for vitrifying radioactive waste.

[0094] The matrix obtained in step (4) included 49.23% by weight of SiO.sub.2, 16.21% by weight of Al.sub.2O.sub.3, 7.56% by weight of CaO, 6.54% by weight of MgO, 10.32% by weight of Fe.sub.2O.sub.3+FeO, 4.25% by weight of Na.sub.2O+K.sub.2O and 1.89% by weight of TiO.sub.2, where the matrix further included 4.09% by weight of at least five compounds selected from the group consisting of MnO, P.sub.2O.sub.5, SO.sub.3, BaO, SrO, ZrO.sub.2, CuO, ZnO, Nb.sub.2O.sub.5, Rb.sub.2O and Y.sub.2O.sub.3.

EXAMPLE 7

[0095] A method for preparing a matrix for vitrifying radioactive waste was provided herein, which was specifically described as follows

[0096] (1) Grinding

[0097] Natural magmatic rocks were used as raw materials and ground.

[0098] (2) Melting

[0099] The ground product was heated and melted at 1500 C. for 3 h.

[0100] (3) Moulding

[0101] The melted product was moulded in a mold preheated to 850 C.

[0102] (4) Annealing

[0103] The moulded product was kept at 700 C. for 1 h and cooled to room temperature at a rate of 2 C./min to produce the matrix for vitrifying radioactive waste.

[0104] The matrix obtained in step (4) included 45.52% by weight of SiO.sub.2, 14.12% by weight of Al.sub.2O.sub.3, 9.31% by weight of CaO, 7.28% by weight of MgO, 11.56% by weight of Fe.sub.2O.sub.3+FeO, 5.51% by weight of Na.sub.2O+K.sub.2O and 2.12% by weight of TiO.sub.2, where the matrix further included 4.58% by weight of at least five compounds selected from the group consisting of MnO, P.sub.2O.sub.5, SO.sub.3, BaO, SrO, ZrO.sub.2, CuO, ZnO, Nb.sub.2O.sub.5, Rb.sub.2O and Y.sub.2O.sub.3.

EXAMPLES 8-14

[0105] A method for preparing a matrix for vitrifying radioactive waste was provided herein, which was specifically described as follows.

[0106] (1) Grinding

[0107] Natural magmatic rocks were used as raw materials and ground.

[0108] (2) Melting

[0109] The ground product was heated and melted at 1450-1500 C. for 3-4.5 h.

[0110] (3) Moulding

[0111] The melted product was moulded in a mold preheated to 700-850 C.

[0112] (4) Annealing

[0113] The moulded product was kept at 600-700 C. for 1-2 h and cooled to room temperature at a rate of 1-2 C./min to produce the matrix for vitrifying radioactive waste.

[0114] The matrix obtained in step (4) included 45%-65% by weight of SiO.sub.2, 9%-18% by weight of Al.sub.2O.sub.3, 4%-12% by weight of CaO, 3%-10% by weight of MgO, 6%-16% by weight of Fe.sub.2O.sub.3+FeO, 2%-9% by weight of Na.sub.2O+K.sub.2O and 1%-5% by weight of TiO.sub.2, where the matrix further included 1%-5% by weight of at least five compounds selected from the group consisting of MnO, P.sub.2O.sub.5, SO.sub.3, BaO, SrO, ZrO.sub.2, CuO, ZnO, Nb.sub.2O.sub.5, Rb.sub.2O and Y.sub.2O.sub.3. The compositions of matrices prepared in Examples 8-14 were shown in Table 1.

TABLE-US-00001 TABLE 1 Compositions of the matrices of Examples 8-14 Exam- Exam- Exam- Exam- Exam- Exam- Exam- ple 8 ple 9 ple 10 ple 11 ple 12 ple 13 ple 14 Compo- (wt. (wt. (wt. (wt. (wt. (wt. (wt. sitions %) %) %) %) %) %) %) SiO.sub.2 45.32 47.19 50.80 52.73 55.95 58.32 62.07 Al.sub.2O.sub.3 13.55 14.22 14.40 13.15 12.30 17.24 15.50 CaO 9.35 9.19 7.92 8.61 6.54 4.56 5.41 MgO 4.33 4.45 4.47 6.37 3.50 3.59 3.13 Fe.sub.2O.sub.3 + 15.65 13.91 9.81 9.46 9.04 9.58 6.92 FeO Na.sub.2O + 3.61 4.63 7.55 4.29 8.26 2.99 4.25 K.sub.2O TiO.sub.2 4.02 2.95 2.16 1.41 1.02 2.06 1.04 Other 4.17 3.46 2.89 3.98 3.39 1.66 1.05 com- ponents

EXAMPLE 15

[0115] A matrix for vitrifying radioactive waste was prepared herein according to the process in any one of Examples 5-14, where the matrix included 49.70% by weight of SiO.sub.2, 14.83% by weight of Al.sub.2O.sub.3, 8.76% by weight of CaO, 4.27% by weight of MgO, 10.52% by weight of Fe.sub.2O.sub.3+FeO, 4.78% by weight of Na.sub.2O, 1.99% by weight of K.sub.2O and 3.16% by weight of TiO.sub.2, where the matrix further included 1.99% by weight of at least five compounds selected from the group consisting of MnO, P.sub.2O.sub.5, SO.sub.3, BaO, SrO, ZrO.sub.2, CuO, ZnO, Nb.sub.2O.sub.5, Rb.sub.2O and Y.sub.2O.sub.3.

EXAMPLE 16

[0116] A matrix for vitrifying radioactive waste was prepared herein according to the process in any one of Examples 5-14, where the matrix included 47.73% by weight of SiO.sub.2, 14.22% by weight of Al.sub.2O.sub.3, 9.29% by weight of CaO, 4.81% by weight of MgO, 13.01% by weight of Fe.sub.2O.sub.3+FeO, 2.19% by weight of Na.sub.2O, 1.48% by weight of K.sub.2O and 3.37% by weight of TiO.sub.2, where the matrix further included 3.90% by weight of at least five compounds selected from the group consisting of MnO, P.sub.2O.sub.5, SO.sub.3, BaO, SrO, ZrO.sub.2, CuO, ZnO, Nb.sub.2O.sub.5, Rb.sub.2O and Y.sub.2O.sub.3.

EXAMPLE 17

[0117] A method for preparing a glass wasteform of radioactive waste was provided herein, which was specifically described as follows.

[0118] (1) Grinding and Mixing

[0119] 93% by weight of the matrix mentioned above and 7% by weight of simulated radioactive waste were ground and mixed to produce a mixture, where the simulated radioactive waste was MoO.sub.3 or Nd.sub.2O.sub.3, and the grinding was performed by a ball mill, and the mixture had a particle size less than 200 mesh.

[0120] (2) Melting

[0121] The mixture was heated and melted at 1100 C. for 4.5 h.

[0122] (3) Moulding

[0123] The melted product was moulded in a mold preheated to 700 C.

[0124] (4) Annealing

[0125] The moulded product was kept at 600 C. for 2 h and cooled to room temperature at a rate of 1 C./min to produce the glass wasteform of the radioactive waste (i.e., the glass wasteform of the simulated radioactive waste).

EXAMPLE 18

[0126] A method for preparing a glass wasteform of radioactive waste was provided herein, which was specifically described as follows.

[0127] (1) Grinding and Mixing

[0128] 99% by weight of the matrix prepared by the above method and 1% by weight of simulated radioactive waste were ground and mixed to produce a mixture, where the simulated radioactive waste was MoO.sub.3 or Nd.sub.2O.sub.3, and the grinding was performed by a ball mill, and the mixture had a particle size less than 200 mesh.

[0129] (2) Melting

[0130] The mixture was heated and melted at 1300 C. for 3 h.

[0131] (3) Moulding

[0132] The melted product was moulded in a mold preheated to 850 C.

[0133] (4) Annealing

[0134] The moulded product was kept at 700 C. for 1 h and cooled to room temperature at a rate of 2 C./min to produce the glass wasteform of the radioactive waste (i.e., the glass wasteform of the simulated radioactive waste).

EXAMPLE 19

[0135] A method for preparing a glass wasteform of radioactive waste was provided herein, which was specifically described as follows.

[0136] (1) Grinding and Mixing

[0137] 96% by weight of the matrix prepared by the above method and 4% by weight of simulated radioactive waste were ground and mixed to produce a mixture, where the simulated radioactive waste was MoO.sub.3 or Nd.sub.2O.sub.3, and the grinding was performed by a ball mill, and the mixture had a particle size less than 200 mesh.

[0138] (2) Melting

[0139] The ground product was heated and melted at 1200 C. for 4 h.

[0140] (3) Moulding

[0141] The melted product was moulded in a mold preheated to 780 C.

[0142] (4) Annealing

[0143] The moulded product was kept at 650 C. for 1.5 h and cooled to room temperature at a rate of 1.5 C./min to produce the glass wasteform of the radioactive waste (i.e., the glass wasteform of the simulated radioactive waste).

EXAMPLE 20

[0144] A method for preparing a glass wasteform of radioactive waste was provided herein, which was specifically described as follows.

[0145] (1) Grinding and Mixing

[0146] 94% by weight of the matrix prepared by the above method and 6% by weight of simulated radioactive waste were ground and mixed to produce a mixture, where the simulated radioactive waste was MoO.sub.3 or Nd.sub.2O.sub.3, and the grinding was performed by a ball mill, and the mixture had a particle size less than 200 mesh.

[0147] (2) Melting

[0148] The mixture was heated and melted at 1160 C. for 3.5 h.

[0149] (3) Moulding

[0150] The melted product was moulded in a mold preheated to 760 C.

[0151] (4) Annealing

[0152] The moulded product was kept at 630 C. for 1.2 h and cooled to room temperature at a rate of 1.2 C./min to produce the glass wasteform of the radioactive waste (i.e., the glass wasteform of the simulated radioactive waste).

EXAMPLE 21

[0153] A method for preparing a glass wasteform of radioactive waste was provided herein, which was specifically described as follows.

[0154] (1) Grinding and Mixing

[0155] 98% by weight of the matrix prepared by the above method and 2% by weight of simulated radioactive waste were ground and mixed to produce a mixture, where the simulated radioactive waste was MoO.sub.3 or Nd.sub.2O.sub.3, and the grinding was performed by a ball mill, and the mixture had a particle size less than 200 mesh.

[0156] (2) Melting

[0157] The mixture was heated and melted at 1230 C. for 3.8 h.

[0158] (3) Moulding

[0159] The melted product was moulded in a mold preheated to 830 C.

[0160] (4) Annealing

[0161] The moulded product was kept at 680 C. for 1.7 h and cooled to room temperature at a rate of 1.8 C./min to produce the glass wasteform of the radioactive waste (i.e., the glass wasteform of the simulated radioactive waste).

EXAMPLE 22

[0162] A glass wasteform of radioactive waste was prepared herein basically according to the process in any one of Examples 17-21 except for step (1). Specifically, in step (1), 95% by weight of the matrix prepared by the above method and 5% by weight of simulated radioactive waste were mixed, and the simulated radioactive waste was MoO.sub.3.

[0163] In Examples 17-22, the matrix for vitrifying radioactive waste used in step (1) included 45%-65% by weight of SiO.sub.2, 9%-18% by weight of Al.sub.2O.sub.3, 4%-12% by weight of CaO, 3%-10% by weight of MgO, 6%-16% by weight of Fe.sub.2O.sub.3+FeO, 2%-9% by weight of Na.sub.2O+K.sub.2O and 1%-5% by weight of TiO.sub.2, where the matrix further included 1%-5% by weight of at least five compounds selected from the group consisting of MnO, P.sub.2O.sub.5, SO.sub.3, BaO, SrO, ZrO.sub.2, CuO, ZnO, Nb.sub.2O.sub.5, Rb.sub.2O and Y.sub.2O.sub.3. The matrix used in any one of Examples 17-22 may have the same composition as that in any one of Examples 5-14.

[0164] In Examples 17-22, the matrix for vitrifying radioactive waste used in step (1) included 49.70% by weight of SiO.sub.2, 14.83% by weight of Al.sub.2O.sub.3, 8.76% by weight of CaO, 4.27% by weight of MgO, 10.52% by weight of Fe.sub.2O.sub.3+FeO, 4.78% by weight of Na.sub.2O, 1.99% by weight of K.sub.2O and 3.16% by weight of TiO.sub.2, where the matrix further included 1.99% by weight of at least five compounds selected from the group consisting of MnO, P.sub.2O.sub.5, SO.sub.3, BaO, SrO, ZrO.sub.2, CuO, ZnO, Nb.sub.2O.sub.5, Rb.sub.2O and Y.sub.2O.sub.3.

[0165] In Examples 17-22, the matrix for vitrifying radioactive waste used in step (1) included 47.73% by weight of SiO.sub.2, 14.22% by weight of Al.sub.2O.sub.3, 9.29% by weight of CaO, 4.81% by weight of MgO, 13.01% by weight of Fe.sub.2O.sub.3+FeO, 2.19% by weight of Na.sub.2O, 1.48% by weight of K.sub.2O and 3.37% by weight of TiO.sub.2, where the matrix included 3.90% by weight of at least five compounds selected from the group consisting of MnO, P.sub.2O.sub.5, SO.sub.3, BaO, SrO, ZrO.sub.2, CuO, ZnO, Nb.sub.2O.sub.5, Rb.sub.2O and Y.sub.2O.sub.3.

[0166] The grinding in step (1) of any one of Examples 17-22 was crushing by a jaw crusher and then milling by a ball mill. The ground mixture had a particle size less than 200 mesh.

[0167] The raw materials used herein were all commercially available. Unless otherwise specified, the percentages mentioned above referred to mass (weight) or those known to those skilled in the art, and one part by mass (weight) corresponded to one gram or one kilogram.

[0168] In the above embodiments, any value in the range of parameters such as temperature, time, speed and the amount of respective components was applicable.

[0169] Some technical solutions which had been recited in the prior art were not further specified herein.

[0170] The invention is not limited to the above embodiments, and the disclosure of the invention is realizable and has corresponding good effect.