US4432894A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for treatment of detergent-containing radioactive liquid wastes
Assignee: Hitachi Ltd
•
Filing: 1981-03-30
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Granted: 1984-02-21
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Expires: 2001-03-30
Abstract
Abstract A detergent-containing radioactive liquid waste originating from atomic power plants is concentrated to have about 10 wt. % detergent concentration, then dried in a thin film evaporator, and converted into powder. Powdered activated carbon is added to the radioactive waste in advance to prevent the liquid waste from foaming in the evaporator by the action of surface active agents contained in the detergent. The activated carbon is added in accordance with the COD concentration of the radioactive liquid waste to be treated, and usually at a concentration 2-4 times as large as the COD concentration of the liquid waste to be treated. A powdery product having a moisture content of not more than 15 wt. % is obtained from the evaporator, and pelletized and then packed into drums to be stored for a predetermined period.
Inventors
- 👤 Kunio Kamiya
- 👤 Kenji Motojima
- 👤 Kiyomi Funabashi
- 👤 Koichi Chino
- 👤 Susumu Horiuchi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 06:13
CPC Classifications
G; G21; G21F; G21F9/00; G21F9/04; G21F9/06; G21F9/12; G21F9/08
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
63 words
A process for the treatment of detergent-containing radioactive liquid waste, said waste comprising sodium sulfate and powdery ion exchange resin, said process comprising: (a) measuring a chemical oxygen demand concentration of a radioactive liquid waste, (b) adding an adsorbent to the waste in accordance with the measured concentration, and (c) concentrating and drying the waste by heating, thereby converting the waste into powder.
Claim 2
Dependent Claim
63 words
A process for the treatment of detergent-containing radioactive liquid waste, said waste comprising sodium sulfate and powdery ion exchange resin, said process comprising: (a) measuring a chemical oxygen demand concentration of a radioactive liquid waste, (b) adding an adsorbent to the waste in accordance with the measured concentration, and (c) concentrating and drying the waste by heating, thereby converting the waste into powder.
Claim 3
Dependent Claim
28 words
A process according to claim 1, wherein the powder contains 15 wt. % moisture or less and which further comprises a step of shaping the powder into pellets.
Claim 4
Dependent Claim
28 words
A process according to claim 1 or 2, wherein the adsorbent added to the waste is at a concentration not lower than the measured concentration of the waste.
Claim 5
Dependent Claim
30 words
A process according to claim 3, wherein the adsorbent added to the waste is at a concentration 2 to 4 times as high as the measured concentration of the waste.
Claim 6
Dependent Claim
34 words
A process according to claim 4, wherein powder of at least one member of substance selected from the group consisting of activated carbon, silica gel, molecular sieve and alumina is used as said adsorbent.
Claim 7
Dependent Claim
28 words
The process according to claim 4, wherein the adsorbent added to the waste is at a concentration 3 times as high as the measured concentration of the waste.
Claim 8
Dependent Claim
32 words
A process according to claim 3, wherein powder of at least one member selected from the group consisting of activated carbon, silica gel, molecular sieve, and alumina is used as the adsorbent.
Claim 9
Dependent Claim
92 words
A process for the treatment of detergent containing radioactive liquid waste, said waste comprising sodium sulfate and powdery ion exchange resin, said process comprising: (a) providing detergent containing radioactive liquid waste; (b) concentrating the liquid waste to a known chemical oxidation demand concentration; (c) adding a fixed amount of adsorbent to the liquid waste from (b), the amount of adsorbent added being based on the known chemical oxidation demand concentration of the liquid waste from (b); (d) concentrating and drying the liquid waste from (c) thereby converting the liquid waste into powder.
Claim 10
Dependent Claim
92 words
A process for the treatment of detergent containing radioactive liquid waste, said waste comprising sodium sulfate and powdery ion exchange resin, said process comprising: (a) providing detergent containing radioactive liquid waste; (b) concentrating the liquid waste to a known chemical oxidation demand concentration; (c) adding a fixed amount of adsorbent to the liquid waste from (b), the amount of adsorbent added being based on the known chemical oxidation demand concentration of the liquid waste from (b); (d) concentrating and drying the liquid waste from (c) thereby converting the liquid waste into powder.
Claim 11
Dependent Claim
60 words
A process according to claims 1, 2 or 8, wherein the powder is formed by feeding the radioactive liquid waste to a thin film evaporator comprising a vessel having inside a rotary shaft provided with wiping blades and having a heating means, and concentrating and drying the liquid waste therein by heating, thereby converting the liquid waste to powder form.
Claim 12
Dependent Claim
27 words
A process according to claim 9, wherein the adsorbent added to the waste is at a concentration not lower than the measured concentration of the liquid waste.
Claim 13
Dependent Claim
32 words
A process according to claim 10, wherein the adsorbent added to the liquid waste is at a concentration 2 to 4 times as high as the measured concentration of the liquid waste.
Claim 14
Dependent Claim
32 words
A process according to claim 11, wherein powder of at least one member selected from the group consisting of activated carbon, silica gel, molecular sieve, and alumina is used as the adsorbent.
Claim 15
Dependent Claim
32 words
A process according to claim 10, wherein powder of at least one member selected from the group consisting of activated carbon, silica gel, molecular sieve, and alumina is used as the adsorbent.
Claim 16
Dependent Claim
28 words
A process according to claim 8, wherein the powder contained 15 wt. % moisture or less and which further comprises a step of shaping the powder into pellets.
Claim 17
Dependent Claim
27 words
A process according to claim 8, wherein the adsorbent added to the liquid waste is at a concentration not lower than the known concentration of the waste.
Claim 18
Dependent Claim
30 words
A process according to claim 15, wherein the adsorbent added to the waste is at a concentration 2 to 4 times as high as the known concentration of the waste.
Claim 19
Dependent Claim
26 words
The process according to claim 15, wherein the adsorbent added to the waste is at a concentration of 3 times the known concentration of the waste.
Claim 20
Dependent Claim
32 words
A process according to claim 8, wherein powder of at least one member selected from the group consisting of activated carbon, silica gel, molecular sieves, and alumina is used as the adsorbent.
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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) | 1987-02-20 | 1987-08-22 | 1988-02-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-02-20 | 1991-08-22 | 1992-02-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-02-20 | 1995-08-22 | 1996-02-21 | $7700.00 | Window Closed / Lapsed |