electron beam irradiation and its...
TRANSCRIPT
Electron beam irradiation and its applications
Siriwan Krainara
Beam dynamics group
Accelerator Technology Division
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EB irradiation Tasks
Motivation
Introduction
Electron beam source
Electron beam irradiation
Irradiation applications
Summary
Motivation
A filling time of the storage is approximately 1 hour and 2 times per day
The booster is available about 22 hours daily.
Beam Test Facility (BTF) at Booster Synchrotron
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Introduction: History of irradiation
1930: Electron beam source (DC high voltage generator, Van der Graaff)
1950: E-beam irradiation was developed for Nuclear irradiation A commercial use for nuclear power plants (cobalt-60 has to be manufactured in a
nuclear reactor)
1950: First commercialized e-beam sterilization by Ethicon, a division ofJohnson & Johnson
1952: Dr. Arthur Charlesby found the cross-linking of polyethylene
1961: The production of polyethylene wire in Japan.
1970: Industrial radiation processing with electron beams
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Introduction: Irradiation applications
The irradiation of materials with electron beams or X rays Physical properties
Chemical properties
Biological properties
Cover a very wide range of accelerators technology. Curing ink
Coatings
Sterilization of medical products
Disinfection and preservation of food
The emerging applications include treatment of waste waters andflue gases
IAEA, 2011
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Introduction: Energy range for application
IAEA, 2013
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Introduction: Around the World
EB Facilities South America
Brazil USA China Japan World
(200 keV – 10 MeV) 20 18 >500 >140 >300 >1800
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Introduction: In Thailand
Energy range: 20 MeVMaximum beam power: 10 kWDose rate: 25 kGyPrice: 270 million baht from Mevex Corporation Ltd. company Food Gemstone
Profit/year: 120 million baht/year
http://www.tint.or.th/
Current particle accelerators used in Thailand about 30machines with the beam energy more than 6MeV (http://www.ams.cmu.ac.th)
Electron beam therapy (EBT)
Electron: Internal mammary, Breast cancer, Skin cancer
X-ray: Brain tumor, Head and neck cancer, Cervical cancer,Ovarain cancer, Spinal metastasis, Prostate cancer, Lungcancer
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Name of organizations Accelerator
energy
Beam
power
Purpose
TINT 20 MeV 10 kW Coloring of gemstone
Thai Klinipro Co. Ltd. 1.8 - 2.4 MeV 10 kW Sterilization of doctor gown
IBA S&I (Thailand) Ltd. 15 MeV 8.5 kW Upgrading of gemstone
Synergy Health (Thailand) Ltd. 3 - 10 MeV 1 - 50 kW Sterilization of medical devices and
packaging, polymers improvement, and
gemstone coloring
Electron beam sources
http://www.iba-industrial.com/accelerators
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Dynamitron
Van der Graaf
Rhodotron
Linac
High voltage
Electron beam irradiation
Energy = penetration
Up to 10 MeV: No radioactivity induced
Electron beam properties Beam directed toward products
Finite product penetration
Controlled treatment zones
High dose delivery giving short treatment
Wide range of energy and power ratings
Equipment can be switched on and off Power = treatment speed P (kW) = E (MeV) x I (mA)
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X-ray processing
Generated by electrons decelerated in high atomic number material (Tantalum, Gold,…)
Bremsstrahlung (braking or deceleration radiation)
High penetration compared to electrons
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EB or X-rays ? Required penetration?
Depends on product density/thickness to be treated
Required throughput? Depends on power of equipment
Required homogeneity of treatment? X-ray better than electron beam
(especially for high density products)
IBA and IPEN-CNEN/SP
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Units of radiation dose
The absorbed dose (D), is the amount ofenergy absorbed per unit mass of irradiatedmatter at a point in the region of interest.
Dose absorbed by the irradiated materialaccompanied by 1 joule (100 ergs) ofenergy.
Treatment dose = quantity of electrons per surface unit measured in Gray The original unit is the rad [100 erg/g]; it is now being widely replaced by the
SI unit, the gray (Gy) 1 Gray = 1 Joule / kg = 1 W.s / kg = 100 rad Dose = k . beam current / scan . product speed (at given energy)
Applications Dose requirements
Environments uGy
Sterization of food 15-30 kGy
Polymerizing 25-50 kGy
Grafting 25-50 kGy
Crosslinking 50-150 kGy
Degrading 500-1500 kGy
Gemstones >> 1500 kGy
Therapy 1-100 Gray
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Electron beam irradiation processing
Applications
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Electron interaction
Ionization radiation is almost entirely absorbed by theelectronic structure of absorber which increases theenergy level of its orbital electron
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Electron beam irradiation processing
Cross-linking
Curing
Grafting
Degradation
Stephen C. Lapin, 2014
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Electron beam irradiation processing (continue...)
Cross-linking
Curing
Grafting
Chain session or Degrading
Energy: 0.5 - 3 MeVBeam current: 50 - 100 mAMaterial: Polymer ( Polyethylene, EVA or EPDM), rubberApplication: Wire, cable
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Electron beam irradiation processing (continue...)
Cross-linking
Curing
Grafting
Chain session or Degrading
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InksPrintingPackagingCoating on metal, wood, glass.
Low energy
Electron beam irradiation processing (continue...)
Cross-linking
Curing
Grafting
Chain session or Degrading
Grafting
Battery separator membranes Fuel cell membranes Absorbents for metal ions Substrates for cell tissue growth Ion exchange membranes
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Electron beam irradiation processing (continue...)
Cross-linking
Curing
Grafting
Chain session or Degradation
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PTFE (Polytetrafluoroethylene or Teflon)CelluloseWood
M. S. Khan et al., 2008
Improvement of properties
Biological and medical sterilization
Food irradiation
Gemstone coloring
Environment treatment
Others
Applications of Radiation Technology20/33
Polymer modification Common polymers (Polyethylene ….)
Monomer, oligomer
Rubber
Commercial products Wire and cable stand higher temperature
Jacketing for central heating and plumbing
Heat-shrinking products are given a memory
Gaskets, seals & other molded parts
Piping and tubing
Polyethylene foam sheet
Hydrogels
Improvement of properties21/33
Robert, W.H, Maranne, E.H, 2012
Improvement of properties (Continue…)
Vulcanization: Convert natural rubber or related polymers into more
durable materials via the addition of sulfur or otherequivalent curatives or accelerators.
Viscosity, stress, relaxation
Treatment of Tires Reduction in material
Higher production rates
Construction of green tiresChakraborty, S.K., 2010
Heat and pressure
Heat and pressure
EB irradiation
Vulcanized rubber
Rubber compound
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Improvement of properties (Continue…)
Semiconductor (> 100 kGy): The fast recovery diodes, power diodes, bipolarpower transistors, power MOSFETs, power rectifiers, IGBT’s, thyristors, and silicon-controlled rectifiers. Decrease the minority carrier diffusion length
Increase electrical property
Improves switching speed
Battery: Surface grafting of acrylic acid creates films Control the ion flow between the cathode and anode of small lithium
Longer useful life than films
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Biological and medical sterilizations
Formed polymers and composite structures and even ceramics for medical products while not losing flexibility.
The sterilization of packaged devices in packaging operations.
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Syringes Catheters DrainsTubing Culture tubes Drain pouchesBandages Absorbent GlovesSurgical gowns Hand towels Lab ware
Food irradiation1. Radappertization:
Reduce the levels of pathogenic and spoilage microorganisms
2. Radurization: Reduce the need for preservatives and fumigation
treatments,
Extend shelf life
3. Radicidation: Pasteurization
4. Radiation disinfestation: Destroy insects or pests
5. Radiation sprout inhibition: Delay the onset of natural processes such as fruit
ripening and sprouting of bulbs and tubers.
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Food irradiation (Continue…)
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Range Applications
Low
(<1
kGy) Sprout inhibition in bulbs and tubers 0.03-0.15 kGy
Delay in fruit ripening 0.25-0.75 kGyInsect disinfestations 0.07-1.00 kGy
Med
ium
Dos
e(1
-10
kGy)
Reduction of spoilage microbes in meat, poultry and seafood under refrigeration 1.50-3.00 kGyReduction of pathogenic microbes in fresh and frozen meat, poultry and seafood 3.00-7.00 kGyReducing microorganisms in spices 10.00 kGy
Gemstones coloring
Improving the color of glass and gemstones: 50-10000Gy
Topaz Peal Citrine Ametista Diamond Quartz Spodumene (LiAlSi2O6)
Topaz
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Ti, V, Cr, Mn, Fe, Co, Ni, Cu, … Color centers
Environments treatment
IAEA, 2013
Flue Gas Cleaning
Wastewater
Sludge treatment
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Phase Objects Additives ProcessingGas Flue gas Sox, NOx Removal
VOC Organic compounds Degradation removalLiquid Drinking water Chemical pollutants Degradation removal
Wastewater Bacteria, viruses, parasites HygenizationIndustrial waste Organic and nonorganic
compoundsDegradation removal
Solild Sewage sludge Bacteria, viruses, parasites Degradation removalSolid material Architure wastes Transformation
Flue Gas Cleaning
Summary
Applications Energy PowerX-ray sterilization 10 MeV 130 kWSurface sterilization Low energy 1 kWMedical product sterilization, food 2 - 10 MeV 5 - 25 kWPolymer pipes cable 5 MeV 50 kWPolymerization 10 MeV 130 kWDiodes of BHEL power reduce time 2-10 MeV 0.5 kWGemstones 3 - 50 MeV 10 - 500 kWEnvironment 0.5 - 2.5 MeV 100 kW
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SPS electron beam parameters at SLRI
Beam parameters LBT HBT
Energy 40 MeV 1.0 GeV
Beam current 50 mA 15 mA
Pulse width 2 us 8.5 ns
LBT
HBT
(SLRI Tech. 2006)
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Thank You