Patent US4743376A successfully refreshed from Google Patents.
Patent US4710318A successfully refreshed from Google Patents.
US4710318A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of processing radioactive waste
Assignee: Hitachi Ltd
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Filing: 1985-07-31
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Granted: 1987-12-01
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Expires: 2005-07-31
Abstract
Abstract This invention relates to a method of processing radioactive waste, comprising the steps of converting organic radioactive waste into inorganic waste, pulverizing the inorganic waste, and solidifying the pulverized product with an inorganic hardening agent. According to the present invention, a solidified body having money-saving characteristics and a high volume reducing effect and capable of standing all kinds of weather condition excellently for a long period of time can be obtained.
Inventors
- 👤 Susumu Horiuchi
- 👤 Shin Tamata
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 21:37
CPC Classifications
G; G21; G21F; G21F9/00; G21F9/04; G21F9/06; G21F9/28; G21F9/30; G21F9/301; G21F9/302; G21F9/14
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
142 words
A method of processing radioactive organic waste occurring in a nuclear power plant for storage, comprising: reducing the volume of said radioactive organic waste, wherein said radioactive organic waste includes at least one of a spent ion exchange resin and spent filter assistant by converting said radioactive organic waste to inorganic waste by way of an oxidation decomposition process with liquid hydrogen peroxide, said at least one of said spent ion exchange resin and said spent filter assistant being decomposed into water and carbon dioxide by way of the oxidation decomposition process with said hydrogen peroxide liquid to leave a residue of inorganic waste; neutralizing the residue of the inorganic waste with an alkali substance; pulverizing the residue of the inorganic waste; and packing the pulverized inorganic waste in a container with an inorganic hardening agent to solidify the resulting mixtures therein.
Claim 2
Independent Claim
142 words
A method of processing radioactive organic waste occurring in a nuclear power plant for storage, comprising: reducing the volume of said radioactive organic waste, wherein said radioactive organic waste includes at least one of a spent ion exchange resin and spent filter assistant by converting said radioactive organic waste to inorganic waste by way of an oxidation decomposition process with liquid hydrogen peroxide, said at least one of said spent ion exchange resin and said spent filter assistant being decomposed into water and carbon dioxide by way of the oxidation decomposition process with said hydrogen peroxide liquid to leave a residue of inorganic waste; neutralizing the residue of the inorganic waste with an alkali substance; pulverizing the residue of the inorganic waste; and packing the pulverized inorganic waste in a container with an inorganic hardening agent to solidify the resulting mixtures therein.
Claim 3
Dependent Claim
34 words
A process according to claim 1, wherein 95 to 98% by weight percent of the at least one of spent ion exchange resin and spent filter assistant organic waste is converted to inorganic waste.
Claim 4
Dependent Claim
19 words
A process according to claim 1, wherein after pulverizing and before packing, the inorganic waste is formed into pellets.
Claim 5
Dependent Claim
26 words
A process according to claim 3 wherein the radioactive organic waste is spent ion exchange resin and the pellets can withstand a load of 1 kg.
Claim 6
Dependent Claim
20 words
A process according to claim 3 wherein the volume reduction ratio is in the range of about 1/3.9 to 1/173.
Claim 7
Dependent Claim
19 words
A process according to claim 3 wherein the weight reduction ratio is in the range of 1/2.2 to 1/100.
Claim 8
Independent Claim
158 words
A method of processing radioactive organic waste in a slurry occurring in a nuclear power plant for storage, comprising: reducing the volume of said radioactive organic waste, wherein said radioactive organic waste includes at least one of a spent ion exchange resin and spent filter assistant by converting said radioactive organic waste to inorganic waste by way of an oxidation decomposition process with hydrogen peroxide liquid in the presence of one of ferric ions and chromate ions, so that said at least one of said spent ion exchange resin and said spent filter assistant is decomposed into water and carbon dioxide by way of the oxidation decomposition process with the hydrogen peroxide liquid to leave a residue of inorganic waste; neutralizing the residue of inorganic waste with an alkali substance; heating the neutralized residue of inorganic waste to concentrate the same; pulverizing the neutralized and concentrated residue of inorganic waste; and pelletizing the pulverized residue of inorganic waste.
Claim 9
Independent Claim
158 words
A method of processing radioactive organic waste in a slurry occurring in a nuclear power plant for storage, comprising: reducing the volume of said radioactive organic waste, wherein said radioactive organic waste includes at least one of a spent ion exchange resin and spent filter assistant by converting said radioactive organic waste to inorganic waste by way of an oxidation decomposition process with hydrogen peroxide liquid in the presence of one of ferric ions and chromate ions, so that said at least one of said spent ion exchange resin and said spent filter assistant is decomposed into water and carbon dioxide by way of the oxidation decomposition process with the hydrogen peroxide liquid to leave a residue of inorganic waste; neutralizing the residue of inorganic waste with an alkali substance; heating the neutralized residue of inorganic waste to concentrate the same; pulverizing the neutralized and concentrated residue of inorganic waste; and pelletizing the pulverized residue of inorganic waste.
Claim 10
Dependent Claim
27 words
A method according to claim 7, wherein the oxidation-decomposition occurs in the presence of a catalyst selected from the group consisting of ferric sulfate and potassium chromate.
Claim 11
Dependent Claim
25 words
A process according to claim 7, wherein the hardening agent is selected from the group consisting of sodium silicate, potassium silicate, calcium silicate and cement.
Claim 12
Dependent Claim
30 words
The process according to claim 7, wherein oxidation occurs at a temperature of 80°-100° C. as well as in the presence of compressed air, said compressed air being supplied constantly.
Claim 13
Dependent Claim
31 words
The process according to claim 10, wherein the OH radical is produced which works on cross-linked portions of the resin to convert the same into carbon, hydrogen, water and carbon dioxide.
Claim 14
Dependent Claim
35 words
The process according to claim 7, wherein the concentration of ferric ion is in the range of 0.02-0.06 mol/liter for waste and ion exchange resin, and in a greater range for waste cation exchange resin.
Claim 15
Dependent Claim
20 words
The process according to claim 7, wherein the neutralized waste is concentrated to 18 weight percent solids prior to pulverizing.
Claim 16
Dependent Claim
21 words
A process according to claim 7, wherein the ion exchange resin is anion exchange resin and the catalyst is potassium chromate.
Claim 17
Dependent Claim
26 words
A process according to claim 7, wherein the radioactive organic waste is spent ion exchange resin and the pellets can withstand a load of 1 kg.
Claim 18
Dependent Claim
18 words
A process according to claim 7, wherein the heated, neutralized waste is pulverized in a centrifugal film drier.
Claim 19
Dependent Claim
17 words
A process according to claim 7 wherein the alkali substance is a 20% solution of sodium hydroxide.
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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) | 1990-11-30 | 1991-06-01 | 1991-12-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-11-30 | 1995-06-01 | 1995-12-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-11-30 | 1999-06-01 | 1999-12-01 | $7700.00 | Window Closed / Lapsed |