Patent US4620947A successfully refreshed from Google Patents.
US4620947A
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Solidification of aqueous radioactive waste using insoluble compounds of magnesium oxide
Assignee: CHEM-NUCLEAR SYSTEMS Inc COLUMBIA SOUTH CAROLINA A DE CORP
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Filing: 1983-10-17
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Granted: 1986-11-04
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Expires: 2003-10-17
Abstract
Abstract Firm gel structures are formed from hot aqueous radioactive waste solutions containing boric acid by adding powdered magnesium oxide or magnesium hydroxide followed by addition of calcium oxide or calcium hydroxide. Cement may be introduced after addition of the magnesium compound without interfering with subsequent gel reactions. Product rigidity imparted by the gel enables reduction of typical cement usage up to 50% or more in the processing of radioactive boric acid concentrates. This results in more waste being solidified per container, less exothermic heat generation, greater shipping efficiency, and improved resistance to aqueous leaching of radionuclides.
Inventors
- 👤 John E. Carlson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 12:07
CPC Classifications
G; G21; G21F; G21F9/00; G21F9/04; G21F9/06; G21F9/16; G21F9/162; G21F9/165; C; C04; C04B; C04B28/00; C04B28/02; C04B28/04; C04B2111/00; C04B2111/00474; C04B2111/00767; Y; Y02; Y02W; Y02W30/00; Y02W30/50; Y02W30/91
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
84 words
A process for the treatment of radioactive waste which comprises: (a) first adding a sufficient amount of a magnesium oxide compound to an aqueous boric acid-containing radioactive waste and allowing the magnesium oxide and boric acid to react; (b) adding cement to the reacted mixture (a) and uniformly dispersing said cement; and (c) then adding and dispersing a sufficient amount of a compound selected from the group consisting of calcium hydroxide and calcium oxide to (b) to cause the formation of a gel matrix.
Claim 2
Dependent Claim
84 words
A process for the treatment of radioactive waste which comprises: (a) first adding a sufficient amount of a magnesium oxide compound to an aqueous boric acid-containing radioactive waste and allowing the magnesium oxide and boric acid to react; (b) adding cement to the reacted mixture (a) and uniformly dispersing said cement; and (c) then adding and dispersing a sufficient amount of a compound selected from the group consisting of calcium hydroxide and calcium oxide to (b) to cause the formation of a gel matrix.
Claim 3
Dependent Claim
24 words
The process of claim 1 wherein the magnesium oxide compound is powdered and selected from the group consisting of magnesium oxide and magnesium hydroxide.
Claim 4
Dependent Claim
34 words
The process of claim 1 wherein the amount of the magnesium oxide compound added is at least about 50 percent by weight, of the boric acid (H 3 BO 3 ) in the waste.
Claim 5
Dependent Claim
24 words
The process of claim 1 wherein the amount of cement added is at least 50 percent by weight of the boric acid waste liquid.
Claim 6
Dependent Claim
28 words
The process of claim 1 wherein the amount of calcium oxide or calcium hydroxide is at least about 1/4 of the weight of the boric acid waste liquid.
Claim 7
Dependent Claim
14 words
The process of claim 1 wherein the waste comes from a pressurized water reactor.
Claim 8
Dependent Claim
22 words
The process of claim 1 wherein the waste comes from a boiling water reactor, and boric acid is added to the waste.
Claim 9
Dependent Claim
17 words
The process of claim 1 wherein the magnesium oxide compound will pass through a 200 mesh screen.
Claim 10
Dependent Claim
101 words
A process for the treatment of radioactive waste which comprises: (a) first adding, under continuous agitation, a sufficient amount of a powdered magnesium oxide or magnesium hydroxide to an aqueous radioactive waste solution containing boric acid, the temperature of the water solution being 55-95 degrees C. to produce a magnesium borate derivative; (b) adding cement, under continuous agitation, to the magnesium borate derivative; and (c) then adding, under continuous agitation, after the cement has been dispersed, a sufficient amount of a compound selected from the group consisting of calcium oxide and calcium hydroxide to b) to produce a gel matrix structure.
Claim 11
Dependent Claim
101 words
A process for the treatment of radioactive waste which comprises: (a) first adding, under continuous agitation, a sufficient amount of a powdered magnesium oxide or magnesium hydroxide to an aqueous radioactive waste solution containing boric acid, the temperature of the water solution being 55-95 degrees C. to produce a magnesium borate derivative; (b) adding cement, under continuous agitation, to the magnesium borate derivative; and (c) then adding, under continuous agitation, after the cement has been dispersed, a sufficient amount of a compound selected from the group consisting of calcium oxide and calcium hydroxide to b) to produce a gel matrix structure.
Claim 12
Dependent Claim
27 words
The process of claim 9 wherein about 0.5 mole of the magnesium compound and 1.5 moles of the calcium compound are added per mole of boric acid.
Claim 13
Dependent Claim
21 words
The gel matrix structure produced by any one of claims 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-11-03 | 1990-05-05 | 1990-11-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-11-03 | 1994-05-05 | 1994-11-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-11-03 | 1998-05-05 | 1998-11-04 | $7700.00 | Window Closed / Lapsed |