EP0186677B1 - Verfahren zur aufbereitung radioaktiver abfälle, die aus aktiniden mit mittlerer und/oder langer halbwertszeit bestehen - Google Patents
Verfahren zur aufbereitung radioaktiver abfälle, die aus aktiniden mit mittlerer und/oder langer halbwertszeit bestehen Download PDFInfo
- Publication number
- EP0186677B1 EP0186677B1 EP19850902571 EP85902571A EP0186677B1 EP 0186677 B1 EP0186677 B1 EP 0186677B1 EP 19850902571 EP19850902571 EP 19850902571 EP 85902571 A EP85902571 A EP 85902571A EP 0186677 B1 EP0186677 B1 EP 0186677B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- elements
- actinide
- mixture
- life
- emitter
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Images
Classifications
-
- G—PHYSICS
- G21—NUCLEAR PHYSICS; NUCLEAR ENGINEERING
- G21G—CONVERSION OF CHEMICAL ELEMENTS; RADIOACTIVE SOURCES
- G21G1/00—Arrangements for converting chemical elements by electromagnetic radiation, corpuscular radiation or particle bombardment, e.g. producing radioactive isotopes
- G21G1/04—Arrangements for converting chemical elements by electromagnetic radiation, corpuscular radiation or particle bombardment, e.g. producing radioactive isotopes outside nuclear reactors or particle accelerators
-
- G—PHYSICS
- G21—NUCLEAR PHYSICS; NUCLEAR ENGINEERING
- G21F—PROTECTION AGAINST X-RADIATION, GAMMA RADIATION, CORPUSCULAR RADIATION OR PARTICLE BOMBARDMENT; TREATING RADIOACTIVELY CONTAMINATED MATERIAL; DECONTAMINATION ARRANGEMENTS THEREFOR
- G21F9/00—Treating radioactively contaminated material; Decontamination arrangements therefor
Definitions
- the present invention relates to a device for conditioning radioactive waste consisting essentially of actinides with a medium and / or long period.
- the first solution consists in storing this waste in stable geological layers, after having introduced them into glass or resin matrices.
- the second solution consists in transforming this waste in a nuclear reactor, by reaction of fission or transmutation into elements with much shorter period or into fissile isotopes usable in nuclear reactors.
- the first solution requires a complex packaging infrastructure in glass or resin matrices.
- the stability of these matrices is not guaranteed in the very long term.
- the second solution firstly requires the separation of the actinides with a high degree of purity before irradiation so as not to increase the anti-reactivity. Furthermore, it is not certain that the yield from the cracked actinide / actinide formed operation is positive or sufficient, and this technique, which appears difficult to implement, cannot lead to total destruction of the actinides. In addition, it has the disadvantage of being of high cost and requiring the use of a nuclear reactor.
- the present invention specifically relates to a device for conditioning radioactive waste consisting essentially of actinides with a long and / or medium period, which overcomes the drawbacks mentioned above, while offering sufficient guarantees of safety and security.
- the quantities of actinide elements with long and / or medium period, of actinide emitting elements a with short period (at most 100 years) and of light elements being chosen in such a way that a sufficient quantity of neutrons is produced for obtain the destruction of actinide elements with a long and / or medium period by autofission and / or capture and / or decay, and their conversion into non-radioactive or radioactive elements of short period or into actinide elements which can be used industrially.
- the reaction (a, n) between the emitter a with a period at most equal to 100 years and a light element such as boron-11, fluorine, beryllium, carbon, etc. is used to produce fast neutrons with an energy higher than 4 MeV and these fast neutrons formed "in situ" in the packaging are used to split or transmute actinides with long or medium period and to initiate the autofission chain.
- the packaging can be reprocessed in order to recover the interesting actinide elements.
- actinides with a medium period are understood to mean actinides with a period of 100 to 1,000 years and by actinides with a long period, actinides with a period greater than 1,000 years.
- Examples of long-lived actinides include 23 'Np, 243 Am, 245 Cm, 242 PU.
- the overall yield of the autofission ultimately depends on the fission yield, but this operation is limited by the quantity of neutrons produced which is itself conditioned by the number of particles emitted.
- the number of particles a produced in a period Ta per gram of actinide is approximately 1.2-10 21 particles a.
- R is the reaction yield (a, n) the number of neutrons produced per gram of actinide in a period T "is about 1.2.10 21 R neutrons. Also, to maximize the production of neutrons, there must be a period T ⁇ as short as possible, but remaining compatible with the waste produced (cooling time and quantity produced) and there must be a maximum yield R which is linked to the nature of the light element used.
- the mixture of actinides and of the light element (s) is placed in a sealed envelope, reflecting or absorbing neutrons, preferably spherical with a diameter of less than 10 cm, so defining a central region constituted by a mixture of the actinide emitting element or elements a having a period at most equal to 100 years and of the light element or elements capable of generating neutrons by reaction (a, n), and a peripheral region surrounding the central region constituted by a mixture of the emitting actinide element or elements with a medium and / or long period and the light element or elements capable of generating neutrons by reaction ( ⁇ , n).
- the mixture placed inside a sealed envelope, reflecting or absorbing neutrons comprises three regions, a first central region constituted by a mixture of the emitting actinide element or elements a having a period at most equal to 100 years with the light element or elements capable of generating neutrons by reaction (a, n), a second region surrounding the central region constituted by a mixture of at least one actinide emitting element a of medium period with at least one light element capable of generating neutrons by reaction (a, n ), and a third region surrounding the second region constituted by a mixture of the or of the actinide emitting elements has a long period with the light element (s) capable of generating ne utrons by reaction (a, n).
- the various constituents, actinides and light elements can be homogeneously mixed inside a sealed envelope, reflecting or absorbing neutrons, whose shape and dimensions are not limited by the effectiveness of neutron collisions on actinides, as in the previous embodiments; one could, for example, use a cylindrical container with a diameter of about one meter.
- the mixture of actinides and light elements confined in said container can be obtained from a mixture of the various constituents in a finely divided state, for example in the form of powders having particle sizes less than 20 ⁇ m.
- the powder mixture is generally subjected to compaction followed possibly by sintering.
- the mixture can also be obtained directly in the form of a solid solution, by direct formation of borides or berylliides of the actinide elements, such as UB. 2 CmB ,, AmB 6 , AmBe., NpB, etc.
- At least part of the actinide elements entering into the composition of the mixture is associated with boron or beryllium in the form of boride or berylliide.
- actinides and light elements are combined in the form of compounds such as borides or berylliides, it is possible to obtain a very intimate mixture and to precisely control the concentration of actinides by controlling the stoichiometric ratio of compound and avoiding the presence of precipitates of light elements or actinides.
- the characteristics of any one of the first two modes are combined with those of the third, by disposing in a container such as that used in the third embodiment, mini- spheres with concentric layers, i.e. spherical envelopes with a diameter of less than 10 cm. waterproof, reflecting or absorbing neutrons, each containing mixtures of ⁇ -emitting actinide element (s), a emitting element (s) a and light element (s) arranged in concentric layers as in any of the first two embodiments.
- mini-spheres the diameter of which is preferably of the order of a millimeter, can be obtained, for example, by the sol-gel process as described by HD RINGEL and E.
- the actinide elements with a long period can be chosen from 237Np, 243 Am, 2 4 5 Cm , 2 4 2Pu.
- the actinide emitting elements a having an average period can be chosen from 24 Am and 242m Am.
- the actinide emitting elements a having a period at most equal to 100 years are advantageously chosen from 242 Cm, 244 Cm, 238 Pu, 241 pu and z32 U.
- the light elements used are advantageously chosen from '° B, 11 B, 9 Be, C, O and F.
- the light element which has a high reaction yield (a, n) is chosen, for example beryllium whose yield is approximately 70 neutrons for 10 6 particles a or boron whose yield is around 20 neutrons for 10 6 ⁇ particles, with a particles of 5.3 MeV.
- each fast neutron produced reacts with an actinide atom to cause its fission, which, on the other hand, leads to the production of more than two fast neutrons on average.
- a large number of long-term actinide fissions can be obtained by promoting neutron collisions with actinides by a chosen distribution of the different atoms in the mixture as seen above and by choosing so appropriate the relative concentrations of the different actinide elements and the light elements as a function of the mean fission cross section of the actinides and of the balance of transmutation and fission reactions, and of the concentration of neutrons formed.
- the overall performance of the autofission can be further increased by placing a layer of neutron reflective material between the outer shell and the mixture of the actinide elements with the light element (s).
- the neutron reflective material can be boron, water, graphite, steel, etc.
- the actinide elements present in the packaging device of the invention are preferably used in a relatively pure form to obtain the best fission yield.
- the actinide elements are isolated during the reprocessing of the irradiated fuels by extraction techniques by acid solvent and they are recovered in the organic solution or the aqueous extraction solution by precipitation techniques, which makes it possible to separate them from the other elements with a good degree of purity.
- a mixture of several actinides is generally obtained and this mixture can be used directly in the packaging device of the invention.
- the device comprises a spherical outer envelope 1 made for example of steel, inside which is placed the mixture of actinide elements and light elements.
- the second embodiment of the device of the invention was used, namely an arrangement of the mixture in the form of three concentric regions of different compositions.
- the first region 3 which constitutes the source of neutrons and comprises a mixture of emitting elements a with short period with a light element capable of producing neutrons by reaction ( ⁇ , n).
- This region 3 is constituted, for example, by a gram of a source of 242 cm and / or 244 cm with beryllium or boron.
- the second region 5 which is constituted by a layer of an actinide element with a medium period such as 242 Am which has a high neutron capture section and also plays the role of emitter.
- this layer also contains boron-11 or beryllium.
- the thickness of the second region 5 can be about 1 cm or more.
- the third region 7 which constitutes the target is formed of a mixture of long-lived actinides such as 237 Np with 9 Be or "B.
- the thickness of this third region is substantially equal to the thickness of the second region 5.
- This third region 7 is surrounded by a layer 9 of neutron reflective material constituted by boron-10, thanks to the use of beryllium in the first central region 3. fast neutrons are produced with a relatively high yield.
- 242 Cm we produce about 2.10 ° neutrons / gram per second and if we use z44 Cm, we produce about 4 108 neutrons per gram per second.
- neutrons are used to split the americium 241 present in zone 5 which in turn emits other neutrons capable of splitting and / or transforming by reaction of transmutation, fission and / or capture the neptunium 237 present in the region 7 in 232 U.
- the weight concentrations of actinides and of light elements are of the order of 95% and 5% respectively.
Landscapes
- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- High Energy & Nuclear Physics (AREA)
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Physical Or Chemical Processes And Apparatus (AREA)
- Measurement Of Radiation (AREA)
- Luminescent Compositions (AREA)
Claims (19)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FR8408770A FR2565397B1 (fr) | 1984-06-05 | 1984-06-05 | Dispositif de conditionnement de dechets radioactifs constitues par des actinides a periode moyenne et/ou longue |
FR8408770 | 1984-06-05 |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0186677A1 EP0186677A1 (de) | 1986-07-09 |
EP0186677B1 true EP0186677B1 (de) | 1989-03-15 |
Family
ID=9304707
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP19850902571 Expired EP0186677B1 (de) | 1984-06-05 | 1985-06-04 | Verfahren zur aufbereitung radioaktiver abfälle, die aus aktiniden mit mittlerer und/oder langer halbwertszeit bestehen |
Country Status (5)
Country | Link |
---|---|
EP (1) | EP0186677B1 (de) |
JP (1) | JPS61502415A (de) |
DE (1) | DE3568895D1 (de) |
FR (1) | FR2565397B1 (de) |
WO (1) | WO1985005726A1 (de) |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH073474B2 (ja) * | 1990-07-13 | 1995-01-18 | 動力炉・核燃料開発事業団 | 放射性廃棄物の消滅処理方法 |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
BE544752A (de) * | 1956-01-27 | 1900-01-01 | ||
BE638862A (de) * | 1963-10-18 | |||
DE2249429A1 (de) * | 1972-10-09 | 1974-04-18 | Kernforschung Gmbh Ges Fuer | Verfahren zur umwandlung von langlebigen spaltprodukten oder radionukliden mit langer halbwertszeit |
-
1984
- 1984-06-05 FR FR8408770A patent/FR2565397B1/fr not_active Expired
-
1985
- 1985-06-04 EP EP19850902571 patent/EP0186677B1/de not_active Expired
- 1985-06-04 DE DE8585902571T patent/DE3568895D1/de not_active Expired
- 1985-06-04 WO PCT/FR1985/000139 patent/WO1985005726A1/fr active IP Right Grant
- 1985-06-04 JP JP50247585A patent/JPS61502415A/ja active Pending
Also Published As
Publication number | Publication date |
---|---|
JPS61502415A (ja) | 1986-10-23 |
FR2565397A1 (fr) | 1985-12-06 |
DE3568895D1 (en) | 1989-04-20 |
WO1985005726A1 (fr) | 1985-12-19 |
EP0186677A1 (de) | 1986-07-09 |
FR2565397B1 (fr) | 1986-08-22 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
Rinehart | Design characteristics and fabrication of radioisotope heat sources for space missions | |
US6738446B2 (en) | System and method for radioactive waste destruction | |
US4663110A (en) | Fusion blanket and method for producing directly fabricable fissile fuel | |
EP0231710B1 (de) | Verfahren zum Betreiben eines Kernreaktors mit Verschiebung des Neutronenspektrums unter Verwendung von Stabbündeln zur Wasserverdrängung | |
US9646729B2 (en) | Laser sintering systems and methods for remote manufacture of high density pellets containing highly radioactive elements | |
EP0186677B1 (de) | Verfahren zur aufbereitung radioaktiver abfälle, die aus aktiniden mit mittlerer und/oder langer halbwertszeit bestehen | |
US3269915A (en) | Neutron irradiation process for producing radioisotopes wherein target isotope is shielded from thermal neutrons | |
US4344912A (en) | Method of increasing the deterrent to proliferation of nuclear fuels | |
BE1008202A3 (fr) | Assemblage combustible contenant du plutonium et coeur de reacteur utilisant un tel assemblage. | |
ES2219963T3 (es) | Procedimiento para la fabricacion de pastillas de combustible nuclear de tipo mox. | |
US8755483B2 (en) | Nuclear fuel | |
US5419886A (en) | Method for generation of finely divided reactive plutonium oxide powder | |
US3360477A (en) | Neutron source | |
Takibaev et al. | Transmutation of zirconium-93 in high-flux blanket of fusion neutron source | |
KR20000068512A (ko) | 연소도가 높은 원자로 연료체 및 제조 방법 | |
Loewen | Heavy-metal nuclear power: could an unconventional coolant enable reactors to burn radioactive waste and produce both electric power and hydrogen? | |
US2809157A (en) | Neutronic reactor | |
JPH05180971A (ja) | 超ウラン元素の消滅処理炉心 | |
US20220246314A1 (en) | 210Pb and 227Ac Precursor Isotopes in Radioisotope Power Systems | |
RU2119202C1 (ru) | Мишень для накопления транскюриевых элементов | |
FR2693826A1 (fr) | Procédé d'exploitation de réacteurs nucléaires et réacteur nucléaire à variation de spectre en faisant application. | |
Collins et al. | Evaluation of Actinide Partitioning and Transmutation in Light-Water Reactors | |
Chuvilo et al. | Nuclear fuel cycle using nuclear power facilities based on subcritical blankets driven by proton accelerator | |
JPS5836759B2 (ja) | 核燃料要素 | |
FR3121263A1 (fr) | Assemblage de combustible d’uranium de réacteur à eau légère et procédé de fonctionnement d’un cycle de combustible nucléaire |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
17P | Request for examination filed |
Effective date: 19860116 |
|
AK | Designated contracting states |
Kind code of ref document: A1 Designated state(s): BE DE GB |
|
RAP1 | Party data changed (applicant data changed or rights of an application transferred) |
Owner name: COMMISSARIAT A L'ENERGIE ATOMIQUE |
|
17Q | First examination report despatched |
Effective date: 19880118 |
|
GRAA | (expected) grant |
Free format text: ORIGINAL CODE: 0009210 |
|
AK | Designated contracting states |
Kind code of ref document: B1 Designated state(s): BE DE GB |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: GB Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 19890315 |
|
REF | Corresponds to: |
Ref document number: 3568895 Country of ref document: DE Date of ref document: 19890420 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: BE Effective date: 19890630 |
|
GBV | Gb: ep patent (uk) treated as always having been void in accordance with gb section 77(7)/1977 [no translation filed] | ||
BERE | Be: lapsed |
Owner name: COMMISSARIAT A L'ENERGIE ATOMIQUE Effective date: 19890630 |
|
PLBE | No opposition filed within time limit |
Free format text: ORIGINAL CODE: 0009261 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT |
|
26N | No opposition filed | ||
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: DE Effective date: 19900301 |