Thermal-Mechanical Response of Non-Uniformly Heated LEU Foil Based Target

2011 ◽  
Author(s):  
Kyler K. Turner ◽  
Gary L. Solbrekken ◽  
Charlie W. Allen
Keyword(s):  
Mechanical Response ◽  
Metal Foil ◽  
Transfer Coefficients ◽  
Technetium 99M ◽  
Heat Transfer Coefficients ◽  
Plate Design ◽  
Enriched Uranium ◽  
Aluminum Plates ◽  
Sandwiched Structure ◽  
Global Threat

Technetium-99m is a diagnostic radiopharmaceutical that is currently used in 80% of the global nuclear diagnostic imaging procedures. The parent isotope for technetium-99m is molybdenum-99, most commonly obtained through the irradiation of high enriched uranium (HEU) targets. In accordance with the Department of Energy’s Global Threat Reduction Initiative (GTRI) an effort is underway to develop a process to produce molybdenum-99 using low enriched uranium (LEU) targets to maintain production yield relative to HEU targets. Conversion of targets to LEU material effectively mandates that the most efficient process is to cast LEU in the form of a metal foil as opposed to current powder based dispersion designs for HEU. Using a foil requires a significant modification to the current target design. One design concept uses an LEU foil sandwiched between two nominally flat aluminum plates. The LEU is enclosed in the sandwiched structure by welding the aluminum plates together about their edges. The plate design is inspired by high density monolithic LEU fuel plates with the exception that the LEU is not bonded to the aluminum plates nor is it necessary to clamp the plate edges to prevent lateral translation. The lack of bonding between the LEU foil and the plates allows the edges of the plate to be cut off so the foil can be removed after irradiation to be chemically processed. The un-heated edges of the plate target produce 3-D temperature gradients that induce plate deformations. This paper will review thermal mechanical response of an LEU foil based molybdenum-99 plate target geometry. This study describes the effect of various edge holding conditions, thermal loads, and heat transfer coefficients on the thermal-induced deflection and stress in the plates.

Thermal-Mechanical Response of Non-Uniformly Heated Nominally Flat and Curved LEU Foil Based Target

2012 ◽  
Author(s):  
Kyler K. Turner ◽  
Gary L. Solbrekken ◽  
Charlie W. Allen
Keyword(s):  
Mechanical Response ◽  
Three Dimensional ◽  
Department Of Energy ◽  
Transfer Coefficients ◽  
Technetium 99M ◽  
Plate Design ◽  
Enriched Uranium ◽  
Aluminum Plates ◽  
Sandwiched Structure ◽  
Global Threat

Technetium-99m is a radiopharmaceutical currently used in 85% of all diagnostic imaging procedures. The relative long lived parent isotope of technetium-99m is molybdenum-99, which is commonly produced by irradiating highly enriched uranium. In accordance with the Department of Energy: National Nuclear Security Administration’s Global Threat Reduction Initiative an effort is underway to develop low enriched uranium based molybdenum-99 production concepts. Achieving comparable molybdenum-99 yields in a low enriched uranium target effectively mandates the use of a high density metal low enriched uranium foil. Using a foil requires a significant modification to the current highly enriched uranium dispersion target designs. One design concept uses a low enriched uranium foil sandwiched between either two flat or curved aluminum plates. The low enriched uranium is enclosed in the sandwiched structure by welding the aluminum plates together about their edges. The plate design is inspired by low enriched uranium fuel plates with the exception that the low enriched uranium is not bonded to the aluminum plates nor is it necessary to clamp the plate edges to prevent lateral translation. The lack of bonding between the low enriched uranium foil and the plates allows easy removal of the foil after irradiation for chemically processing and separation. The un-heated edges of the plate target produce three-dimensional temperature gradients inducing deformations and stress. This paper will review the thermal mechanical response of a low enriched uranium foil based molybdenum-99 production target. This study describes the effect of various curvatures, thermal loads, and heat transfer coefficients on the thermal-induced deflection and stress.

Experimental Testing of Annular Target Surrogates for the Production of Molybdenum-99

2012 ◽  
Author(s):  
Philip F. Makarewicz ◽  
Srisharan Garg Govindarajan ◽  
Gary L. Solbrekken
Keyword(s):  
Experimental Testing ◽  
Thermal Contact ◽  
Cooling Water ◽  
High Volume ◽  
Metal Foil ◽  
High Volume Production ◽  
Volume Production ◽  
Enriched Uranium ◽  
Global Threat ◽  
Target Design

Technetium-99m (Tc-99m) is a diagnostic radiopharmaceutical that is currently used about 100,000 times daily for diagnostic imaging procedures globally [1]. The parent isotope for Tc-99m is molybdenum-99 (Mo-99), most commonly obtained through the irradiation of high enriched uranium (HEU). In accordance with the Department of Energy’s Global Threat Reduction Initiative (GTRI), an effort is underway to develop a process to produce Mo-99 using low enriched uranium (LEU). One method utilizes LEU cast in the form of a metal foil as opposed to current powder based dispersion designs for HEU. New high-volume production LEU target concepts need to be analyzed to assure safe, reliable operation during all stages of production as use of a foil requires a significant modification to the current target design. Analytic and numeric models have been built to simulate the thermal-mechanical behavior of LEU-foil based targets under irradiation conditions. Experimental testing is being used to validate the models. Heating conditions are controlled by heater placement and cooling water circulation to place the target interfaces into controlled states of compression and tension. Thermocouples are used to measure the temperature at key locations so that the thermal contact resistance can be evaluated and compared with the predictions.

Thermal-Mechanical Analysis of Varying Boundary Conditions on a LEU Foil Based Molybdenum-99 Plate Processing Target

2010 ◽  
Author(s):  
Kyler K. Turner ◽  
Gary L. Solbrekken ◽  
Charlie W. Allen
Keyword(s):  
United States ◽  
Boundary Conditions ◽  
Nuclear Reactor ◽  
The United States ◽  
Mechanical Analysis ◽  
Metal Foil ◽  
Enriched Uranium ◽  
Aluminum Plates ◽  
Thermal Mechanical Analysis ◽  
The Impact

Technetium-99m is a diagnostic radio-pharmaceutical that is currently used in 85% of the United States diagnostic imaging procedures [1]. All supplies of technetium-99m’s parent isotope molybdenum-99 currently originate from the irradiation of high enriched uranium (HEU) in nuclear reactor facilities located outside the United States. In accordance with the Global Threat Reduction Initiative all uranium used in future molybdenum-99 production will use low enriched uranium (LEU). Conversion to LEU material effectively mandates using LEU in the form of a metal foil as opposed to current powder based dispersion designs for HEU. Using a foil requires a significant modification to the current target design. One design approach uses an LEU foil sandwiched between two nominally flat aluminum plates. The LEU is enclosed in the sandwiched structure by welding the aluminum plates together about their edges. The plate design is inspired by LEU fuel plates with the exception that the LEU is not bonded to the aluminum plates nor is it necessary to clamp the plate edges to prevent lateral translation. This paper will review the thermal-mechanical analysis of an LEU based molybdenum-99 target with plate geometry. This study describes the impact of boundary conditions on the thermally-induced stress and strain in the aluminum plates.

A Novel Method for Molybdenum-99/Technetium-99m Recovery via Anodic Carbonate Dissolution of Irradiated Low-Enriched Uranium Metal Foil

2015 ◽  
Vol 54 (2) ◽  
pp. 712-719 ◽  
Author(s):  
M. Alex Brown ◽  
Artem V. Gelis ◽  
Jeffrey A. Fortner ◽  
James L. Jerden ◽  
Stan Wiedmeyer ◽  
...  
Keyword(s):  
Metal Foil ◽  
Carbonate Dissolution ◽  
Uranium Metal ◽  
Technetium 99M ◽  
Novel Method ◽  
Enriched Uranium

Exergy and sensibility analysis of each individual effect in a kraft multiple effect evaporator

TAPPI Journal ◽  
2019 ◽  
Vol 18 (10) ◽  
pp. 607-618
Author(s):  
JÉSSICA MOREIRA ◽  
BRUNO LACERDA DE OLIVEIRA CAMPOS ◽  
ESLY FERREIRA DA COSTA JUNIOR ◽  
ANDRÉA OLIVEIRA SOUZA DA COSTA
Keyword(s):  
Optimization Problem ◽  
Real Data ◽  
Kraft Pulping ◽  
Steam Temperature ◽  
Input Flow ◽  
Transfer Coefficients ◽  
Heat Transfer Coefficients ◽  
Multiple Effect ◽  
Sensibility Analysis ◽  
Exergetic Analysis

The multiple effect evaporator (MEE) is an energy intensive step in the kraft pulping process. The exergetic analysis can be useful for locating irreversibilities in the process and pointing out which equipment is less efficient, and it could also be the object of optimization studies. In the present work, each evaporator of a real kraft system has been individually described using mass balance and thermodynamics principles (the first and the second laws). Real data from a kraft MEE were collected from a Brazilian plant and were used for the estimation of heat transfer coefficients in a nonlinear optimization problem, as well as for the validation of the model. An exergetic analysis was made for each effect individually, which resulted in effects 1A and 1B being the least efficient, and therefore having the greatest potential for improvement. A sensibility analysis was also performed, showing that steam temperature and liquor input flow rate are sensible parameters.

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