2010 NGSI Summer Interns: Non-Destructive Assay (NDA)

1. 2010NGSI Summer Interns:Non-Destructive Assay (NDA) May-July 2010 Jeff Chapman NDA Team Lead

2. The Non-Destructive Assay (NDA) department is pleased to have: • Three summer interns working on the installation of the Hybrid K-Edge Densitometer (HKED)system at the Radiochemical Engineering Center (REDC) • One summer intern assisting with our understanding in uranyl fluoride deposit formation in uraniumenrichmentfacilities • Interns supporting Safeguards Engagement projects in South Africa, Ukraine, and Kazahkstan(for C. Behan) • For more details on the summer internship programs, refer to Ed Wonder’s August 2009 paper posted at: http://events.energetics.com/univworkshop10/presentations/Ed_Wonder.pdf

3. ORNL Organization (NGSI/NESLS)

4. By way of introduction… Taking a closer look at the students and what they are working on…

5. Alice Begovich Enrolled at UTK for Master of Science in Environmental Engineering To obtain a complete chemical understanding of deposit formation in enrichment plants Graduated from the University of Dayton in May 2010 with a Bachelor of Chemical Engineering I am a vegan Played rugby all four years of my undergraduate education • About Me • My Project • Will provide increased knowledge to NDA developers that may lead to improvement in techniques to measure holdup • Hometown of Knoxville, TN • Working with Jeff Chapman at ORNL • Unique Facts about Me • Future Plans • I play the flute with a band of friends • I have been to Spain and Italy and would love to go back • Want to work toward improving the state of the environment through the use of more nuclear power while also maintaining and improving the safety of nuclear materials

6. Ben Farr PROJECT: Hybrid K-Edge Densitometer This system is used to verify uranium and plutonium concentrations in nuclear fuel reprocessing plants in order to guard against the threat of the diversion of SNM. Undergraduate Senior in Nuclear Engineering at the University of Tennessee The HKED improves safeguards by providing measurements using faster and simpler methods than traditional chemical analyses. Organizations: At UT, I work for Dr. Howard Hall, UT-ORNL Governor’s Chair for Nuclear Security ASSIGNMENT: Create an MCNP model of the system to be used to identify and simulate future improvements. UNIQUE ABOUT ME: FUTURE PLANS: I am getting married this August. I was the UT Drum Major for the 2008 and 2009 football seasons Chelsea, my Fiancée Sophie, our mini Australian Shepherd After graduation, I plan to immediately continue on with my education and earn a Master’s degree in Nuclear Engineering. I hope to contribute to the area of Nuclear Safeguards and Security by pursuing a career in this field.

7. Erik Ellis Living a balanced life between work and recreation Learning about the present and future technologies for safeguarding nuclear material Education is the cornerstone of triumph or failure Career in Engineering Oak Ridge High School Tennessee Tech

9. Key Objectives • Take a part of these various projects, and make it your own: • Radiation Transport Modeling • Chemical Engineering Processes (uranium, recycle) • Electro-mechanical engineering of HKED Subsystems • Algorithms and IC software.

10. Uranium Enrichment: Chemical Reactions Involved in Holdup When moist air infiltrates the system: When oxides or hydroxides are on inner surfaces of metals: With pure metal: (U2F9, UF4 are also possible products)

11. Deposition Characteristics • Deposits increase with time • After initial exposure, rate of deposit generally decreases • Quantities and rates of deposit depend on cleaning procedures, plant operation, and location of deposition site in the facility

12. Uranyl Fluoride Hydrate • UO2F2∙nH2O where • UO2F2= hygroscopic (readily absorbs moisture from air) • Continues to form hydrates until stable compound UO2F2∙2H2O is reached • Then can continue to absorb excess moisture until

13. Participation in the Hybrid K-Edge Densitometer Factory Acceptance Test • Familiarity with performing a vendor’s inspection and test, including quality assurance. • Hands-on use of a working system (3-continuous days) • How to identify performance issues. • How to operate an x-ray machine along with the precautions necessary for safe operation • Specific application or skill learned • Performed calibration verification tests for the XRF, KED, and hybrid KED/XRF. • Mechanical maintenance and upkeep • Acquired detailed information to be used for modeling purposes • Had first-hand access to experts

14. MCNPX for Modeling KED/XRF Systems • Setup of system geometries • More components and detail to be added • Define material composition of components with focus on the sample solution • Need verification of material assumptions and chemistry calculations 3D Rendition of HKED • Define X-ray source energy distribution and beam characteristics • Input distribution from spectrum calculated by program such as SpekCalc (Institute of Cancer Research, UK) or model the x-ray generating tube in MCNP Example Spectrum Generated by SpekCalc

15. Hybrid K-Edge Densitometer System Design for Non-Destructive Assay of Nuclear Materials Hybrid K-Edge Densitometry Electro-Mechanical Design Erik Ellis Tennessee Technological University ■ The X-ray tube(pictured beneath the lead shielding) requires a high voltagegenerator to produce the X-rays ■ The generator then requires acooler to keep the generator operating efficiently and without overheating The radiation detectors require operation at a very low temperature for accurate measurements so they are each paired with a liquid nitrogen dewar Around 77K(-195 C) inside Utilizes x-ray’s for non-destructive assay of nuclear materials (Uranium and Plutonium) CANBERRA Cryo-Cycle Cryostat Nitrogen Cryo-Cycle This Hybrid K-Edge Densitometer uses self-replenishing dewars ■ The built-in power controller keeps the cooler operating within safe limits. The efficiency of the cryocooler and the power controller are very high so the total power consumption is typically 150 –200 watts. ■ Unit makes very little audible noise (<70 dB at 1 m). ■ AMBIENT TEMPERATURE RANGE – 10–35 °C (50–95 °F). ■ The expected life of the cooler is greater than five years in continuous operation. ■“Cryogenic”– Of or relating to low temperatures ■ The Cryo-Cycle Cryostat is a Revolutionary innovation in the field of cryogenically cooled radiation detectors ■ Described as “hybrid” because it utilizes both conventional LN2(liquid nitrogen) and electric cooling First Hybrid K-Edge Densitometer with this technology ■ LN2 CAPACITY – 22 liters (39 lb) ■ LN2 LOSS RATE – <3 liters/day typically (with cryocooler off) ■ COOLING – Forced Air (internal fan). ■ LEVEL INDICATORS – LEDS on central panel indicate high and low LN2 levels. ■ No external hardware, hoses, or cables are required. The Cryo- Cycle Cryostat simply plugs into an AC (90-240 V, 50-60 Hz) power outlet. ■ This cooling system is unique because the boil-off nitrogen no longer has to be replaced but is condensed back into useable liquid N2 using the built in cryocooler ■ It provides the convenience of electric cooling with the reliability of liquid nitrogen (immune to power failure) Traditionally, Liquid nitrogen is placed in a dewar and simply refilled after a month or so when it boils away at room temperature…

16. Detailed Presentations and Posters will be provided • NDA students will host a brown-bag lunch seminar to present the results of their projects. • NDA students will prepare a poster session to be given in August, laboratory wide. • We continue to work with the ORNL program office, Howard Hall, University of Tennessee, Georgia Tech, and SRNL to provide ongoing graduate students to support these NDA and SST endeavors.