NuRAD 8200 – Composite Radiation Shielding

Transcription

NuRAD 8200 – Composite Radiation Shielding
NuRAD 8200 – Composite Radiation
Shielding Construction Materials
Special modular shielding material from low-background and high-density
concrete in unified segments, modules and related building components with
unique features dedicated for nuclear industry, safety and laboratory application.
> Product features
QUALIFICATIONS
Unique composite lead-free building materials based on aggregate with a
very low internal content of radionuclides have been developed specifically
for dry construction of objects with a low internal level of ionizing radiation.
Another composition with very high bulk density in turn enables the
application in the field of radiation safety for shielding both neutron and
gamma radiation in a variety of environments.
Key Features and Benefits:
- effortless, fast, dry masonry and clean construction
- shielding performance / thickness optimization
- robust, solid and self-supporting construction
- rigidity and firm mechanical properties
- variety of surface finishing
- no health hazard, easy decommissioning
The shielding material is protected by
patent, utility and industrial design.
REFERENCES
2013, NuRAD LB235, NuWM MUM,
Low background measuring cell
(tunnel) for free release measurement
of the radioactive waste, ÚJV Řež,
a. s. (Nuclear research institute), Czech
Republic, 1613 bricks in total.
2014, NuRAD HD325, shielding layer
inside the safety entrance door to the
room with the experimental (research)
cyclotron, UJF AV ČR (Nuclear physics
institute, The Academy of sciences of
the Czech Republic), 2 cubic meter
in total.
- special shapes and dimensions available on request
- cost-saving shielding solution
Ref : NUV_PDT_2014_001
The Modular Composite Shielding Construction Material is designed
especially for construction of low background measuring cells, chambers
or rooms. Due to properties of this special shielding system is achieved an
excellent shielding of natural and/or ambient background with significantly
increased sensitivity of the integrated measuring systems necessary for
gamma counting laboratories or for free release measurement (detection
limits easily meet laboratory standards or free release levels). Components of
the materials allow the construction of shielding of different geometries, the
optimization of the number of block layers and the construction of very large
shielding and low-background rooms, where the use of lead is impossible
due to the price or other reasons (shielding of the entire spectrometric
laboratory room).
The other important field in which this system can be applied is radiation
protection or emergency situation - wide variety of shielding walls, floors,
ceilings, vaults, partitions and sleeves (minimize the effects of ionizing
radiation on workers and / or technology - radiation shielding, absorbers and
protection against technological sources of ionizing radiation).
Nuvia - NuRAD 8200 – Composite Radiation Shielding Construction Materials
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Low-background blocks performance: total photon fluence attenuation in lead and in low-activity blocks.
Thickness of pure polyethylene and doped polyethylene equivalent to attenuation of NuRAD8200: Spectrum of CF-252 (mean energy 2MeV).
Half-value layer thickness of high-density material dependence on gamma radiation energy.
All complementary and other construction materials (metal or plastic parts) are carefully
selected to minimize influence of naturally occurring gamma emitters.
System allows the shielding thickness optimization (according to the required application and
parameters) with capability of the additional fortification.
This composite system is a great cost-effective solution (excellent price / value ratio) in
relation to the conventional lead (tungsten, steel) shield solutions and systems.
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> Operational Information
The shapes of individual concrete segments assure easy assembly and installation (easy, dry and clean
construction). A system of locks ensures the stability of the shielding and the simple assembly and disassembly
makes the whole shielding easily transportable. The big shielding walls could be reinforced inserting of
reinforcement rods.
The segment shield is built in accordance with the laying plan in the thickness and the structure of the given
application (calculation).
For manipulation and fixation of individual segments and bricks there are fixturing components, mounts and
holders available.
> Specification data
Types / bulk density
TypeDescriptionBulk density (kg/m3)
LB35Low-background2 350
HD260
High density shielding protection (basalt)
2 600
HD325
High density shielding protection (barite)
3 250
HD400
High density shielding protection (magnetite)
4 000
NS235
Neutron shielding material with high internal hydrogen volume
2 350
Natural contamination
K-40: 10,6 Bq/kg, Ra-226: 1,0 Bq/kg, Th-228: 0,7 Bq/kg (type LB235)
Construction
Blocks with locks, dry walling without fasteners. Self-supporting construction.
Composition
Aggregates and mineral components of cement are made from materials paleozoic geological formations.
Aggregates (grain fraction 0-2 mm, 4-8 mm, 8-11 mm), cement, plasticizer, epoxy resin (low background lintel).
No health hazard, no toxicity, environmentally friendly.
Blocks types
Wall bricks, floor bricks, door bricks, ceiling lintels.
Standard blocks dimensions (width x depth x height)
Wall bricks
Dimensions (w x d x h [mm])
Bulk density [kg/m3]
400 x 200 x 100
2 350
2 600
3 250
4 000
200 x 200 x 100
2 350
2 600
3 250
4 000
400 x 100 x 100
2 350
2 600
3 250
4 000
200 x 100 x 100
2 350
2 600
3 250
4 000
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> Options and ACC
Surface
Variety of surface finishing (application in clean-rooms, decontamination, hydrophobization ...).
Block types
Special sizes/dimensions and block types (corner, top, bottom or lintel elements) are available on user request
and special order on project base.
Auxiliary components
Holders and manipulators for handheld bricks manipulation.
> Performance data
FRMC application
FRMC (free release measurement chamber) application. Low-activity blocks with density of 2,35 g/cm3, inner
cavity dimensions: 1200 (w) x 3000 (d) x 2000 (h) mm. Shielding chamber thickness: walls 400 mm, floor 600
mm, doors 200 mm, ceiling 500 mm.
Decline of the photon ambient dose rate from 101 nSv/h to 33 nSv/h.
Shielding effects of the FRMC chamber for an HPGe detector with Eff 50%:
- The total background count rate decreased to 3%
- The background count rate in the Cs-137 (661 keV) ROI decreased to 2,5%
- The background count rate in the Co-60 (1332 keV) ROI decreased to 3%
Minimum detectable activities (MDA) for HPGe detector with Eff 50%:
- MDA(Cs-137) = 30 Bq
- MDA(Co-60) = 30 Bq
Lead comparison
Low-activity block thickness equivalent to the same photon fluence attenuation as in lead:
- 50 mm of lead: 290 mm for 662 keV (Cs-137), 220 mm for 1332 keV (Co-60)
- 100 mm of lead: 580 mm for 662 keV (Cs-137), 440 mm for 1332 keV (Co-60)
Application
- Shielding chambers, rooms, tunnels - low-level activity measurement (nuclear industry, laboratory, medicine radiotherapy, radiopharmacy, nuclear medicine).
- Shielding wall, maze, floor, ceiling, vault and building components, neutron barriers and layered shielding
systems - radiation protection (working and technological safety).
- Additional shielding layer of a current lead detector shielding and shielding of hot-cells.
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