Electron Beam Irradiation Applications Sunil Sabharwal International Atomic Energy Agency IAEA Atoms for Peace
Greetings from the IAEA! 2
Outline of the presentation • Fundamental aspects of radiation processing using electron beam accelerators • Established applications of electron beam accelerators • Emerging applications and the challenges before electron beam technologists for such applications • Role of IAEA in enhancing applications of electron beam accelerators 3
Greenhouse Effect Issues related to conventional techniques High Energy Consumption ! Toxic residues!! 4
Expectations from new technologies • Energy Saving • Must provide superior products • Environment friendly • Cost effective • Public acceptance 5
How is Radiation Different from Thermal energy ? Thermal energy is very strongly coupled to Translational, Rotational and Vibrational modes of the energy absorber. Ionizing Radiation Ionization, bond rupture and other processes leading to chemical reactions occur P. E. only in the high energy region of the Maxwellian tail. Thermal energy Internuclear distance Ionizing radiation is almost entirely absorbed by the electronic structure of absorber which increases the energy level of its orbital electrons. Effective, Efficient generator of reactive Species. Energy in the form of large quanta can have more pronounced chemical effects than energy in the form of small quanta 6
Effects of radiation on a covalent bond Ionizing Radiation A-B Dissociation AB * AB + + e - Recombination A � + B � Radicals Solvated ions 7
What kind of reactions are amiable with radiation (EB) processing? Production rate (kw-hr) = 3.74x10 -4 G.M.f kg where f is efficiency of radiation absorption • G-value (yield) of reaction should be very high • M - (mol. wt. of product) should be high • Small change produced should have very large effect on the properties • Value addition to the product is very high 8
The real dot -com Free radical, R . Mutli- billion dollar industry providing unique high technology products !!
Applications of Radiation Technology • Crosslinking of polymers • Curing of polymer coatings Radiation • Graft polymerization Chemistry based • Flue gas treatment applications • Waste water treatment Radiation • Sterilization of medical products Biology • Food irradiation based applications • Sewage Sludge Hygienization 10
Electron Accelerators: Tools for radiation processing Electron Accelerator (EB): Energy: low (300-700keV), medium (2-3MeV) high (5-10MeV) Power: Medium (20-100kW) High (0.5-1MW) Electron mode X-ray mode (>2000 worldwide) 11
Penetration Depth of � � -ray and e-beam 12
Applications of Medium Energy Accelerators 13
High Performance Price Plastics Performance Engineering Plastics Standard Plastics Volume 14
PEK PE FP LCP HIGH PERFORMANCE PLASTIC PPS PES HDT>100 o COC PSU ENGINEERING PA4,6 PC BLEND PLASTIC PBT PET PPO HDT>100 o PP-GR PMMA ABS UPGRADATION THROUGH PP PP SAN RADIATION STANDARD PE CROSSLINKING PLASTIC PVC HDT<100 o AMORPHOUS CRYSTALLINE 15
Benefits of crosslinking • Increased tensile strength • Increased form stability • Resistance to deformation • Resistance to solvents • Shrink memory • Viscosity or melt flow behavior change 16
Benefits of Electron Beam crosslinking • Can be carried out at any temperature and in any phase • No toxic additives are required • Crystallinity of the material is retained as crosslinking occurs only in the amorphous phase • Only one parameter viz. Radiation dose to be controlled in the process 17
Comparison of Energy Input of Thermal and Radiation Vulcanization of Rubbers Rubber Vulcanization at 80 kGy = 80 J/g Thermochemical vulcanization of rubber at 150 C to achieve the same crosslinking = 281 J/g Radiation vulcanization is 3-6 times more energy efficient! Ref: V.S.Ivanov, Radiation Chemistry of Polymers, Utrecht (1992) 18
�������������� ������� ������������ � � ������������ � � � � � ����������� Radiation Crosslinking Electron beam Polymer chains Crosslinking Radicals Film, Powder Solution Improvement by crosslinking � �� Heat stability � �� High strength � � �� Processability � �� insoluble 19
Courtesy: Dr Bumsoo Han, EB Tech 20
Value addition to materials using electron beams 21
Unique advantage of electron beam (selective crosslinking) 22
EB crosslinked HDPE 23
Shrinkable Tubes (b) (a) Irradiation Heating for expansion Fix after expansion PE&PP Re-heating for shrink Poly(lactic acid) Expanded size Expanded after irra. Original size Bundled wire 24 Courtesy: Dr M.Tamada, JAEA
Electron Beam Crosslinked Heat-Shrink Products Packaging Tubing Sheets 25
Car Parts Produced by Radiation Crosslinking Technology • Wire and Cable • Foam • Shrinkable Tube • Tire • Polyswitch 26
Applications of Low Energy Accelerators 27
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Electron Beam Curing for Surface Modification Bar Coater Liquid polymer layer EB irradiation Final Cured Surface Substrate (Abrasion, Packaging scratch Sheets resistance, Coating on metal, hardness, wood, glass.. glossy coatings) 30
Energy Demand to Dry/Cure Coatings System Solvent Solvent Water EB cure Solids 30% 40% 40% 100% Diluent heptane toluene water none 98 0 C 111 0 C 100 0 C Boiling - Point, Vapour 35 mm 22 mm Hg 17 mm Hg - pressure at Hg 20 0 C Heat of 76 88 540 - vapourization (cal/gm diluent) Energy to dry 740 555 3390 30 at 1g dried 30 kGy coating Ref: A.J.Berejka, IAEA-TECDOC-1386, 2004, 6 65-72 31
Applications of High Energy Accelerators 32
Electron Beam Sterilization of Life Saving Equipment 33
Enhancing food safety and security Over half the food produced globally is lost, wasted or discarded as a result of inefficiency in the human-managed food chain. 34
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Ref: R.Eustice, NIC-2010, Mumbai 36
Radiation Treatment of Bio-hazards Electron Beam accelerator for treatment of postal mail in US Irradiate packaged goods for sterilization 37
Scale of utilization of radiation in various industries 7% SURFACE CURING 6% 5% 32% WIRE, CABLE, TUBING SHRINK FILM 17% TIRES OTHER 33% SERVICE Over US$ 85 Billion industry! 38
Emerging Applications And New Challenges 39
Electrons Beam Applications for Protection of the Environment Flue gas Purification Wastewater Treatment Sludge Hygienization 40
Tackling environmental challenges Acid rain 41
Electron Beam Flue Gas Treatment (EBFGT) Air Preheater GGH Air Dry ESP Electron Beam Boiler Fertilizer Flue Gas By product By Product Collector Stack Spray Cooler Fertilizer NH 3 Process Vessel 42
SO 2 and NO x removal mechanism HNO 2 OH OH O, OH OH NH 3 NO NO 2 HNO 3 NH 4 NO 3 OH O 2 , OH H 2 O SO 2 HSO 3 SO 3 H 2 SO 4 NH 3 NH 3 O 2 , H 2 O (NH 3 ) 2 SO 2 (NH 4 ) 2 SO 4
��������������������������������������� ������������������ �������������������������������� � � � ���������������������������������������� � ��������������������������������� � ������������������������������������� � ���������������������������������������� � �������������������������������������� � ����������������������������������� Courtesy: Prof A.Chmielewski 44 Set up in collaboration with IAEA
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Polluted industrial and municipal wastewater Dye Detergents Solid waste Pharmaceutical residues Toxic waste…. 46
� ��� ���� ��� � � � �� Principles of Wastewater treatment with e- beam Complete H 2 O,CO 2 Decomposition Harmful Partial Organic Decomposition in Coagu Suspended Waste lation solid Water like Monomer to O H dyes, Polymerization H POPs, Bio- Removal of Drugs Treat Toxic group Water Molecule Removal of Active Radicals Color, Odor IAEA CRP on “Radiation Treatment of 47 W aste Water for Reuse”
DYETEC KAERI EB-TECH Radiolysis Study - Plant Design - P Pl and Installation Lab. Analysis IAEA Korean City of DYECEN BINP Government Daegu IPC - Technical Support - Research Project - Analysis of Economy - Funding from - Consulting - Peaceful use of - Electric Power Local Gov. Budget Radiation Technology - Bio-treatment Established in Collaboration with IAEA 48
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