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Uranium Hexafluoride (UF 6) Cylinders Monitoring Needs George Eccleston & Ed Wonder Discussion with NMMSS Users Group Meeting Las Vegas, NV May 18, 2010 NNSA UF 6 Cylinder Monitoring Study Authors G. R. J. G. D. J. M. Eccleston Babcock Bedell Cefus Hanks Jo Laughter Oakberg Rosenthal Tape Whittaker Consultant LLNL LANL SRNL BNL ORNL Consultant BNL Consultant ORNL Twelve ton Type 48 Y UF 6 Cylinder 1
Cylinders are used to store, transport and process UF 6 • Filled cylinders can be safely handled at contact without radiation shielding (< 3. 0 mrem/hr). Natural background radiation is ~ 0. 04 mrem/hr • Cylinders are easily handled and moved with the proper lifting equipment Cylinders are manufactured and certified to ISO and ANSI specifications 30 B Cylinder at a feed/withdrawal station 2
UF 6 Cylinder Types* Cylinder Model Nominal Maximum 235 U Diameter UF 6 U Enrichment inches kgs % 235 U kgs 1 S 1. 5 0. 45 0. 30 100 0. 30 2 S 3. 5 2. 22 1. 50 100 1. 50 5 A/5 B 5 24. 95 16. 9 100 16. 9 8 A 8 115. 7 78. 2 12. 5 9. 8 12 A/12 B 12 208. 7 141. 1 5. 0 7. 1 30 B 30 2, 277 1, 540 5. 0 77 48 A/X 48 21, 030 14, 219 4. 5 640 48 F 48 27, 030 18, 276 4. 5 822 48 G 48 26, 840 18, 148 1. 0 181 48 Y 48 27, 560 18, 634 4. 5 839 48 H/HX/OM 48 27, 030 18, 276 1. 0 183 For criticality safety, the cylinder diameter is decreased as the uranium enrichment increases * The UF 6 Manual, USEC-651, Rev. 8, January 1999, page 6 3
Most-Used UF 6 Cylinder Types Type 48 Y Cylinder 48 inch diameter • Used for natural and depleted uranium • Holds 12, 500 kgs of UF 6 (8, 450 kgs U) • A 48 Y cylinder filled with natural uranium contains 60. 1 kgs of 235 U. New 48 Y Cylinders Type 30 B Cylinder 30 inch diameter • LEU is shipped in 30 B cylinders in the form of UF 6 from enrichment plants to fabrication plants to make reactor fuel. • Holds 2, 270 kgs of UF 6 (1, 540 kgs U) • A 30 B cylinder filled with 4% enriched uranium contains 61. 6 kgs of 235 U. 30 B Cylinder 4
UF 6 Cylinder Commerce • Thirteen countries have enrichment production capabilities or nearcapabilities (including Argentina, Brazil, Iran, India, and Pakistan). • Eight countries (China, France, Germany, Japan, Netherlands, Russia, United Kingdom, and United States) provide toll enrichment services and supply enriched UF 6 to the commercial nuclear reactor market. • Enrichment capacity is projected to increase by 20% world-wide in the next 5 -10 years, commensurate with reactor construction plans and a shift to higher fuel burn-ups (requiring higher fuel enrichment) • 90% of the world’s enrichment capacity and civil nuclear commerce exists in the nuclear weapon states; 10% in NNWS. • Based on current plans, the world share of enrichment capacity in NNWSs will double from 10% to 20%. • Potential expansion of UF 6 conversion in NNWSs (e. g. , Kazakhstan) 5
Illustrative Worldwide Cylinder Numbers and Flows Cylinder Shipments per Year Type 48 Y 9, 100 cyl/year (~8, 400 kgs U/cyl) Type 30 B 6, 600 cyl/year (~1, 500 kgs U/cyl) 6
UF 6 Cylinders and Enrichment • UF 6 is direct feed material to enrichment plants and is used to produce LEU for reactor power fuel; in addition – UF 6 can be enriched to produce HEU for nuclear explosives. • HEU production requires: 1. 2. • • An operating enrichment cascade, designed for HEU production or sufficiently flexible for such, and UF 6 feed material. 3. At 90% enrichment one SQ = 27. 5 kg Uranium The theft or diversion of UF 6 will become increasingly attractive to States and perhaps even sub-national groups as the capability to enrich uranium becomes more broadly available. The A. Q. Khan network has disseminated centrifuge enrichment information and the barrier to developing enrichment capabilities continues to be lowered. 7
Enriching LEU (4. 0% 235 U) to produce HEU Illustrative 1000 Machine Cascade A 30 B Cylinder filled with 1, 540 kgs of 4. 0% enriched uranium contains 61. 6 kgs of 235 U Product 90% 235 U 56. 7 kgs 2. 04 SQs 3. 3 months/SQ Cascade stages 30 B Cylinder Feed 4% 1, 540 kgs Takes four 5 A cylinders to hold 56. 7 kgs of HEU. Centrifuges/stage 30 B or 48 Y Cylinder Tails 0. 71% Nat. U 1, 483 kgs 8
Type 5 A (5” Diameter) Cylinders are used for HEU • HEU requires containers that have a critically safe geometry • A 5 A cylinder holds up to 24. 95 kgs of UF 6 (16. 8 kgs U) • Isotopic Content Limit: 100% 235 U 5” • One 5 A cylinder filled with 90% 235 U contains 0. 6 SQs of uranium*. • Two cylinders contain 1. 2 SQs 36” Gross Weight 110 lbs * A significant quantity (SQ) of uranium is the approximate amount of nuclear material in respect of which, taking into account any conversion process involved, the possibility of manufacturing a nuclear explosive device cannot be excluded. At 90% enrichment one SQ = 27. 5 kg Uranium 9
Enriching Natural Uranium (0. 71% 235 U) to Produce HEU Illustrative Enrichment Cascade Product 90% 235 U 43. 4 kgs 1. 56 SQs 13. 9 months/SQ 4. 0% 235 U A 48 Y Cylinder filled with 8, 450 kilograms of natural uranium contains 60. 1 kgs 235 U 48 Y Cylinder 0. 71% 235 U Takes three 5 A type cylinders to hold 43 kgs of HEU Feed 8, 450 kgs 0. 71% Nat. U 48 Y Cylinder Tails 8, 407 kgs 0. 25% Depleted U 10
Enrichment Timeline Illustrative Operational Centrifuge Cascade: ~ 1000 machines, ~ 5 SWU/machine/yr • Filled 30 B and 48 Y cylinders are IAEA indirect use material. • Indirect use material consists of 75 kilograms of 235 U enriched to < 20%. • The IAEA detection time for indirect use material is one year. Time required to enrich LEU and Nat. U in filled 30 B and 48 Y UF 6 cylinders UF 6 Cylinder Uranium Type kg 30 B 1, 540 48 Y 8, 452 Feed Cascade Product SWU/yr kg/yr 4. 0 5000 0. 711 5000 235 U % SQs/yr Months/SQ* 100. 6 3. 62 3. 3 24. 0 0. 86 13. 9
UF 6 Cylinder Identification Problems For Both Operators and Inspectors Identification Problems – – – UF 6 cylinders do not have unique identifiers Identification labels are not consistent across manufacturers Labels are subject to harsh conditions and can be difficult to read Cylinders often have multiple labels and IDs and can be confusing Automated methods do not exist to read and identify cylinders Significant effort is spent locating and verifying cylinders. Cylinders with multiple IDs and difficult to read labels 12
UF 6 Cylinders - Multiple Labels * P. Friend, Urenco, D. Lockwood, DOE/NNSA, and D. Hurt, IAEA, “A concept for a world-wide system of identification of UF 6 cylinders, ” 50 th Annual Meeting of the INMM, Tucson, Arizona, July 2009.
Cylinder Shipments and Timely Reporting • Shipments from one site to another can take several months and involve a variety of transportation modes and handling of cylinders and overpacks. – Cylinder shipments typically have few problems but unusual events have occurred. – In unusual cases, when a shipping problem occurs and nuclear material is involved there is detailed follow up and reporting to regulatory agencies. • Implementation of a cylinder monitoring system would aid resolution of problems and enhance safeguards (e. g. , timeliness of detection) and security oversight (e. g. locations and status of cylinders). SHIPS DO GO MISSING Last year the Russian-manned cargo ship had vanished in the Atlantic and was finally located after over a month near Cape Verde off the coast of West Africa, according to French and Russian officials, some 2, 000 miles from its intended port. * *BBC News, Russia Finds Missing Cargo Ship, August 17, 2009 14
Solving the UF 6 Cylinder Identification Problem Industry* is proposing formation of an international working group to: • Develop a global, unique identification (UID) number system for UF 6 cylinders • Develop a method of attaching tamper indicating UID on cylinders • Develop technology to read cylinders • Gain international agreement • Implement UID for existing stocks • Incorporate UID on newly manufactured cylinders • Incorporate into ANSI N 14. 1 and ISO 7195 standards The industry* proposal is limited to UIDs and does not include considerations necessary for cylinder monitoring * P. Friend, Urenco, D. Lockwood, DOE/NNSA, and D. Hurt, IAEA, “A concept for a world-wide system of identification of UF 6 cylinders, ” 50 th Annual Meeting of the INMM, Tucson, Arizona, July 2009. 15
Identifying UF 6 Cylinders • UIDs that enable electronic identification will reduce time and effort in locating cylinders plus decreasing personnel radiation exposure to the benefit of industry and safeguards personnel. • A small number of cylinders (< 20, 000) will need to be monitored. – EZPass routinely monitors and automatically deducts charges for millions of cars passing toll points each year. • A cylinder monitoring system can be slowly implemented and scaled up over time. 16
Beyond Cylinder Identification What is needed to Monitor Cylinders? 1. Each UF 6 cylinder will require a unique identifier (UID). 2. Permanently attach the UID with an integral container to each cylinder – The container would securely hold monitoring electronics. 3. Establish a global cylinder monitoring organization 4. Implement a central registry database of cylinder UIDs 5. Develop robust monitoring and tracking technologies 6. Gain international agreement to implement cylinder monitoring 17
Universal Cylinder Identification Global cylinder monitoring will require implementing universal identification labels and registration of cylinders Cylinder UIDs will benefit both Industry and Safeguards – Enable automated location, identification and verification of cylinder labels. – Safeguard inspections could integrate UIDs into IAEA and State systems to verify shipper/receiver records and correlate cylinders with UF 6 content. – Expanding UIDs to include monitoring capabilities could provide additional cylinder information such as the location, weight, UF 6 content, seals status, etc. 18
Cylinder Registration and Monitoring Benefits Reduce the risk of diversion by States and theft by sub national groups. • Assure positive identification of cylinders and provide timely verification of shipments between shipper and receiver sites; • Reduce personnel effort and improve safeguards and industrial efficiency by automating inventory taking and transit matching; • Enhance safeguards effectiveness through more timely detection of diversion and discourage the use of unregistered cylinders to conceal undeclared production of enriched uranium; and • Augment IAEA State level assessments and support global information analysis in verification of UF 6 commerce and cylinder shipments between States. 19
Conclusions and Recommendations Steps to develop and implement a global cylinder monitoring system: – Participate with industry in an international working group work to define and implement cylinder UIDs that will benefit both industry and safeguards and; – Gain agreement to fabricate a container on each cylinder to hold a monitoring system; – Demonstrate reliable monitoring methods to read, locate and track cylinders; and – Work toward implementation of cylinder monitoring. An effective cylinder monitoring system will require: – – – Cylinder UID’s with a monitoring container that is tamper indicating; A cylinder UID registration database; A global cylinder monitoring organization; Robust monitoring technology to track and provide cylinder information Encryption and other protection to preclude hacking and unauthorized access of the monitoring system; and – Analysis capabilities to verify cylinder locations, shipments and to identify anomalies for inspection follow-up. 20
Seeking Industry Advice and Approaches to the Implementation of Cylinder Monitoring Questions • What are the perceptions and concerns of the UF 6 industry on the impact to operations? • How might cylinder monitoring benefit industry? • What are implications of UIDs, cylinder registry, and tracking cylinders for users of NMMSS? • Other?
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What is Uranium Hexafluoride (UF 6)? • A white crystalline solid at room temperature. • UF 6 is stored and transported in solid form. • UF 6 sublimes (converts from a solid to a gas) at operating pressures below about 21. 9 psia (1. 48 atm) • UF 6 gas is feed material to uranium enrichment plants and to conversion/ fuel fabrication plants, and is used at over 40 commercial nuclear sites world-wide. 23
UF 6 Cylinders Shipments per year by Country and Facility 24
Global Enrichment Plants and SWU capacity 25