US4762646A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of treating radioactive liquids
Assignee: Somafer SA
•
Filing: 1986-10-03
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Granted: 1988-08-09
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Expires: 2006-10-03
Abstract
Abstract The pH of low level radioactive waste liquid is adjusted to be substantially neutral and the liquid is passed to apparatus comprising an atomizer (11) having a turbine (15), air being heated by an electric heater (16) to the atomizer (11) to provide low level radioactive waste particles which may be encapsulated, e.g. in a resin.
Inventors
- 👤 Charles Fougeron
- 👤 Jean J. Fidon
- 👤 Herve Janiaut
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 21:30
CPC Classifications
G; G21; G21F; G21F9/00; G21F9/04; G21F9/20; G21F9/06; G21F9/14; G21F9/16; G21F9/28; G21F9/30; G21F9/301; G21F9/307; Y; Y10; Y10S; Y10S159/00; Y10S159/12; Y10S422/00; Y10S422/903
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
90 words
A method of treating low level radioactive waste liquid to form encapsulated solid for burial, the method comprising the steps of (i) adding caustic solution to the waste liquid to give the liquid a substantially neutral pH value in the range between about 6 and about 8, and agitating and cooling the liquid during the addition, (ii) subjecting the so neutralized liquid to atomization to provide particles of solid radioactive material and water vapor, (iii) separating the particles from the water vapor, and (iv) encapsulating the particles in a matrix.
Claim 2
Independent Claim
90 words
A method of treating low level radioactive waste liquid to form encapsulated solid for burial, the method comprising the steps of (i) adding caustic solution to the waste liquid to give the liquid a substantially neutral pH value in the range between about 6 and about 8, and agitating and cooling the liquid during the addition, (ii) subjecting the so neutralized liquid to atomization to provide particles of solid radioactive material and water vapor, (iii) separating the particles from the water vapor, and (iv) encapsulating the particles in a matrix.
Claim 3
Dependent Claim
14 words
A method according to claim 1 wherein the pH is adjusted to about 6.7.
Claim 4
Dependent Claim
20 words
A method according to claim 2 wherein a strong caustic solution is used to adjust the pH of the liquid.
Claim 5
Dependent Claim
13 words
A method according to claim 3 wherein the strong caustic solution is potash.
Claim 6
Dependent Claim
35 words
A method according to claim 2, wherein the adjustment of the pH takes place in a vessel connected to the atomiser, and the vessel and the atomiser both have inner wall surfaces of stainless steel.
Claim 7
Dependent Claim
63 words
A method according to claim 1 wherein the atomiser has a rotary turbine and the substantially neutral liquid is supplied to the turbine which is rotated to form droplets of the liquid which are then atomised by the passage of hot air into the atomiser to form particles of radioactive material and direct them on to the inner wall surfaces of the atomiser.
Claim 8
Dependent Claim
32 words
A method according to claim 6 wherein the heated air supplied to the atomiser is heated by an electric heater to an inlet temperature of about 400 C. to about 500 C.
Claim 9
Dependent Claim
26 words
A method according to claim 6 wherein the heated air emerges from the atomiser at an outlet temperature of about 105 C. to about 150 C.
Claim 10
Dependent Claim
20 words
A method according to claim 6 wherein the solid particles are separated from water vapor by passage through a filter.
Claim 11
Dependent Claim
28 words
A method according to claim 9 wherein the filter comprises a set of filters each of successively finer sieve size and arranged to return clean air to atmosphere.
Claim 12
Dependent Claim
21 words
A method according to claim 6 wherein the solid particles are passed over a fluidised bed after removal of water vapour.
Claim 13
Dependent Claim
21 words
A method according to claim 6 wherein the solid particles are encapsulated under vacuum in a thermohardenable resin, concrete or bitumen.
Claim 14
Dependent Claim
27 words
A method according to claim 5, including the step of passing demineralised water through the vessel and the atomiser to clean out the vessel and the atomiser.
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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) | 1991-08-09 | 1992-02-08 | 1992-08-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-08-09 | 1996-02-08 | 1996-08-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-08-09 | 2000-02-08 | 2000-08-09 | $7700.00 | Window Closed / Lapsed |