GB2076582A - A Process for Embedding Radioactive Waste in a Metal Matrix - Google Patents

A Process for Embedding Radioactive Waste in a Metal Matrix Download PDF

Info

Publication number
GB2076582A
GB2076582A GB8114682A GB8114682A GB2076582A GB 2076582 A GB2076582 A GB 2076582A GB 8114682 A GB8114682 A GB 8114682A GB 8114682 A GB8114682 A GB 8114682A GB 2076582 A GB2076582 A GB 2076582A
Authority
GB
United Kingdom
Prior art keywords
waste
radioactive
permanent storage
metal matrix
storage container
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.)
Granted
Application number
GB8114682A
Other versions
GB2076582B (en
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nukem GmbH
Original Assignee
Nukem GmbH
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Nukem GmbH filed Critical Nukem GmbH
Priority to GB8114682A priority Critical patent/GB2076582B/en
Publication of GB2076582A publication Critical patent/GB2076582A/en
Application granted granted Critical
Publication of GB2076582B publication Critical patent/GB2076582B/en
Expired legal-status Critical Current

Links

Classifications

    • GPHYSICS
    • G21NUCLEAR PHYSICS; NUCLEAR ENGINEERING
    • G21FPROTECTION AGAINST X-RADIATION, GAMMA RADIATION, CORPUSCULAR RADIATION OR PARTICLE BOMBARDMENT; TREATING RADIOACTIVELY CONTAMINATED MATERIAL; DECONTAMINATION ARRANGEMENTS THEREFOR
    • G21F9/00Treating radioactively contaminated material; Decontamination arrangements therefor
    • G21F9/28Treating solids
    • G21F9/34Disposal of solid waste
    • G21F9/36Disposal of solid waste by packaging; by baling

Landscapes

  • Engineering & Computer Science (AREA)
  • Environmental & Geological Engineering (AREA)
  • Physics & Mathematics (AREA)
  • General Engineering & Computer Science (AREA)
  • High Energy & Nuclear Physics (AREA)
  • Processing Of Solid Wastes (AREA)

Abstract

In disposing of radioactive, particularly tritium containing, waste in lump or particulate form, the waste is compressed at room temperature with metal powder to form shaped elements. The compression is preferably performed in a permanent storage container, when the compaction used effectively unites the metal/waste composite with the container wall.

Description

SPECIFICATION A Process for Embedding Radioactive Waste in a Metal Matrix This invention relates to a process for embedding highly radioactive and medium radioactive, particularly tritium-containing, solid particulate and lump waste in a metal matrix for the purpose of permanent storage.
The operation of nuclear reactors and other nuclear installations, particularly those of the type used for reprocessing spent fuel elements from light water reactors, involves the accumulation of highly active or medium-active solid waste, for example scrap, apparatus components, fuel element heads and bases, fuel element cans, spacers, springs, bolts and other precision components, which have to be conditioned and stored in such a way that the environment is not endangered.
At the present time, this is done by embedding the radioactive solid waste in concrete, followed by subsequent storage in a suitable geological formation. To this end, medium-active and highly active waste has to be conditioned and stored in such a way that the central temperature of the product does not exceed 90 to 95 or. The resulting need to dilute the waste and to increase the storage capacity has an adverse effect so far as concreting is concerned. Another disadvantage lies in the fact that tritium can be released from concreted solid waste, particularly from fuel element cans.
German Offenlegungsschrifts Nos. 26 28 144 and 27 1 7 389 describe processes for embedding waste in a metal matrix. Embedding is achieved by filling the voids between the solid waste with a metal melt consisting of aluminium or of lowmelting metals, such as lead, tin, zinc, copper or metal alloys.
It is also known for example that fuel element cans can be embedded in glass or radioactive waste consolidated to form a compact block by fusion with additives.
All these processes are attended by the disadvantage that volatile radio nuclides, such as tritium or ruthenium for example, are released through the application of high temperatures during the consolidation process and have to be separated off from the waste gas and separately eliminated.
Accordingly, an object of the present invention is to provide a process for embedding radioactive, particularly tritium-containing, waste in a metal matrix in which there is no need to apply high processing temperatures and in which the thermal conductivity and tritium retention capacity of the end product are improved and the extraction of radio nuclides in the event of a fault is reduced at the same time.
According to the invention, this object is achieved in that the waste is compressed into shaped elements with a metal powder at room temperature. These shaped elements are advantageously introduced into permanent storage containers, preferably fine steel cans of the type used for radioactive glass and ceramic waste products. It is of particular advantage, by repeatedly pressing solid waste and metal powder into the permanent storage container, to produce a compact block which is firmly united with the wall of the permanent storage container and which therefore provides for the effective dissipation of heat.
Cold forming by compression is possible with virtually any metal powder. Accordingly, the composition of the metallic matrix may be adapted to the particular application and may be optimised in regard to the type and composition of the waste, to the type of permanent storage and geological formation and also in regard to product properties which could lead to faults.
Aluminium or corrosion-resistant AIMg-alloys are particularly suitable for the consolidation of fuel element cans, particularly in regard to the retention of tritium.
Another advantage of the compression process lies in the fact that the barrier function of the permanent storage container may be advantageously improved. By using internal containers or internal coatings of materials adapted to the particular applications, followed by cold forming, it is possible to establish a homogeneous bond without any cracks or gaps between the waste product and the wall of the container. The release of tritium is further reduced above all by an additional layer of aluminium on the container which prevents the end product from being extracted by water or corrosive solution in the event of faults. It is readily possible in this way to produce beddings containing from 2 to 4 barriers.
The process according to the invention is illustrated by the following Examples: Example 1 Precompacted fuel element can sections approximately 50 mm long (binder: aluminium powder) were used to simulate waste. To produce the shaped elements, aluminium powder was initially introduced after which fuel element can sections were distributed in a layer over the aluminium powder, covered with powder and preconsolidated by gentle compression. After this operation had been repeated several times, the shaped element was finally compressed under a specific pressure of from 5 to 6 Mp/cm2. On completion, the shaped element or pressing has the following properties: waste content 57% by weight density 4.3 g/cc By increasing the number of layers, it is possible further to increase the treatment of waste and hence to reduce the amount of binder required.
Example 2 Size-reduced scrap having a maximum edge length of 10 cm was introduced with fine steel powder into a steel container (300 mm in diameter), pre-compressed in layers and then conditioned by cold forming under a pressure of from 5 to 6 Mp/cm2. A crack-free bond between the container and the product was established by the compression process. On completion, the pressing had the following properties: waste content 57% by weight density 7.7 g/cc

Claims (6)

Claims
1. A process for embedding radioactive particulate or lump waste in a metal matrix, which comprises compressing the waste into shaped elements with a metal powder at room temperature.
2. A process as claimed in Claim 1, wherein the radioactive waste contain tritium.
3. A process as claimed in Claim 1 or 2, wherein the compression process is carried out in a permanent storage container, a compact, solid block firmly united with the wall of the permanent storage container being produced by the repeated compression of waste and metal powder.
4. A process as claimed in any of Claims 1 to 3, wherein the retention capacity for radioactive materials of the permanent storage container is improved by a liner or an internal coating.
5. A process as claimed in any of Claims 1 to 4, wherein the metal powder is aluminium or an aluminium-magnesium alloy.
6. A process for embedding radioactive waste in a metal matrix substantially as described with particular reference to either of the Examples.
GB8114682A 1981-05-13 1981-05-13 A process for embedding radioactive waste in a metal matrix Expired GB2076582B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB8114682A GB2076582B (en) 1981-05-13 1981-05-13 A process for embedding radioactive waste in a metal matrix

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB8114682A GB2076582B (en) 1981-05-13 1981-05-13 A process for embedding radioactive waste in a metal matrix

Publications (2)

Publication Number Publication Date
GB2076582A true GB2076582A (en) 1981-12-02
GB2076582B GB2076582B (en) 1983-06-02

Family

ID=10521779

Family Applications (1)

Application Number Title Priority Date Filing Date
GB8114682A Expired GB2076582B (en) 1981-05-13 1981-05-13 A process for embedding radioactive waste in a metal matrix

Country Status (1)

Country Link
GB (1) GB2076582B (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4491540A (en) * 1981-03-20 1985-01-01 Asea Aktiebolag Method of preparing spent nuclear fuel rods for long-term storage

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4491540A (en) * 1981-03-20 1985-01-01 Asea Aktiebolag Method of preparing spent nuclear fuel rods for long-term storage

Also Published As

Publication number Publication date
GB2076582B (en) 1983-06-02

Similar Documents

Publication Publication Date Title
US3356496A (en) Method of producing high density metallic products
EP0061067B1 (en) Method of storing spent fuel rods in a copper container
KR102704037B1 (en) UN and U₃Si₂ pellets with improved oxidation resistance and grain boundary reinforcement
CA2742613A1 (en) Matrix material of graphite and inorganic binders suitable for ultimate disposal of radioactive wastes, method for producing the same, processing the same and use thereof
GB1590108A (en) Method of treating radioactive waste
EP0044692A2 (en) Arrangements for containing waste material
GB2076582A (en) A Process for Embedding Radioactive Waste in a Metal Matrix
US3344209A (en) Fabrication of materials by high energy-rate impaction
NO793892L (en) PROCEDURE FOR VOLUME REDUCTION, IMMOBILIZATION AND TREATMENT OF HAZARDOUS WASTE
US4472298A (en) Process for embedding radioactive, especially tritium containing waste
Larker Hot isostatic pressing for the consolidation and containment of radioactive waste
Jardine et al. Review of metal-matrix encapsulation of solidified radioactive high-level waste
EP0102246B1 (en) Containment and densification of particulate material
US4432892A (en) Process for the safe intermediate and final storage of tritium
Myrick et al. Fabrication of targets for neutron irradiation of neptunium dioxide
DE3842380A1 (en) Cylindrical container made of steel for the intermediate and final storage of dangerous materials
GB2076581A (en) A Process for Embedding Radioactive Tritium-containing Metal Waste in Concrete
US6143944A (en) Consolidation process for producing ceramic waste forms
JP2003121590A (en) Aluminium-base complex material, production method therefor and complex product therewith
JPS5817399A (en) Method of processing radioactive waste
Geel et al. Embedding of solid high-level wastes into metal and non-metal matrices
JPS58146898A (en) Method of processing radioactive waste
JPS6331758B2 (en)
RU2065221C1 (en) Method for radioactive waste solidification
Lokken Thermal conductivity of multibarrier waste form components

Legal Events

Date Code Title Description
PCNP Patent ceased through non-payment of renewal fee

Effective date: 19940513