Method for vitrification of waste

• US 10,446,286 B2
• Filed: 01/25/2016
• Issued: 10/15/2019
• Est. Priority Date: 05/14/2012
• Status: Active Grant

• Current Assignee: P&t Global Solutions, LLC
• Original Assignee: P&t Global Solutions, LLC
• Inventors: Pegg, Ian L., Gan, Hao, Matlack, Keith S.
• Primary Examiner(s): Johnson, Edward M
• Application Number:
  US15/005,791
• Publication Number:
  US 20160141060A1
• Time in Patent Office: 1,359 Days
• Field of Search: 588 10, 588 11, 588 15, 588313, 588410, 588412, 588901
• CPC Class Codes: C03C 1/002 Use of waste materials, e.g. slags
• CPC Class Codes: G21F 9/16 by fixation in stable solid media G21F9/305 takes precedence
• CPC Class Codes: G21F 9/162 in an inorganic matrix, e.g. clays, zeolites
• CPC Class Codes: G21F 9/305 Glass or glass like matrix C03B5/005 takes precedence; compositional aspects C03C

Abstract

A method for vitrifying waste to prevent the formation of molybdate secondary phases includes forming a feed mixture that includes the waste, a source of vanadium, and at least one of glass frit or glass forming chemicals and vitrifying the feed mixture in a melter to produce a glass product that includes the waste.

Claims

1. A method for vitrifying waste comprising:

forming a feed mixture that includes the waste, a source of vanadium oxide, and at least one of glass frit or glass forming chemicals; and

vitrifying the feed mixture in a melter to produce a glass product that includes the waste.

2. The method of claim 1 wherein the glass product includes no more than 10 wt % vanadium oxide.

3. The method of claim 1 wherein the source of vanadium oxide is an additive that is combined with the waste.

4. The method of claim 1 wherein the source of vanadium oxide is added as a separate component to form the feed mixture.

5. The method of claim 1 wherein the glass frit includes the source of vanadium oxide.

6. The method of claim 1 wherein the waste, the source of vanadium oxide, and at least one of glass frit or glass forming chemicals are each fed separately to the melter.

7. The method of claim 1 wherein the waste, the source of vanadium oxide, and at least one of glass frit or glass forming chemicals are combined before being entering the melter.

8. The method of claim 1 wherein at least one of the source of vanadium oxide, glass frit, or glass forming chemicals is combined with the waste before entering the melter and at least one of the source of vanadium oxide, glass frit or glass forming chemicals is fed separately to the melter.

9. The method of claim 1 wherein the feed mixture includes glass frit and the glass frit includes glass beads, cylindrical glass fiber cartridges, glass powder, and/or glass flakes.

10. The method of claim 1 wherein the method reduces the formation of molybdate yellow phases.

11. The method of claim 1 wherein the method reduces the formation of sulfate salt phases.

12. The method of claim 1 wherein the method reduces the formation of salt phases that incorporate molybdate, sulfate, and pertechnetate.

13. The method of claim 1 wherein the method reduces the formation of salt with one or more of chlorine, fluorine, chromium (chromate), and phosphorous (phosphate).

14. The method of claim 1 wherein the melter includes a joule heated ceramic melter or a cold crucible induction melter or a hot wall induction melter.

15. The method of claim 1 comprising calcining the waste in a separate process step prior to vitrification.

16. The method of claim 1 wherein the method increases the waste loading in the glass product.

17. A method for vitrifying high level radioactive waste comprising:

forming a feed mixture that includes the high level radioactive waste, a source of vanadium oxide, and at least one of glass frit or glass forming chemicals; and

vitrifying the feed mixture in a melter to produce a glass product that includes the high level radioactive waste.

18. The method of claim 17 wherein the glass product includes no more than 10 wt % vanadium oxide.

19. The method of claim 17 wherein the source of vanadium oxide is an additive that is combined with the waste.

20. The method of claim 17 wherein the source of vanadium oxide is added as a separate component to form the feed mixture.

21. A method for vitrifying waste comprising:

mixing the waste, a source of vanadium oxide, and at least one of glass frit or glass forming chemicals to form a feed mixture; and

vitrifying the feed mixture in a melter to produce a glass product that includes the waste;

wherein the waste includes radioactive material.