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1	New Tool for Proliferation Resistance Evaluation Applied to Uranium and Thorium Fueled Fast Reactor Fuel Cycles Metcalf, Richard R. 2009 May 1900 (has links) The comparison of nuclear facilities based on their barriers to nuclear material proliferation has remained a difficult endeavor, often requiring expert elicitation for each system under consideration. However, objectively comparing systems using a set of computable metrics to derive a single number representing a system is not, in essence, a nuclear nonproliferation specific problem and significant research has been performed for business models. For instance, Multi-Attribute Utility Analysis (MAUA) methods have been used previously to provide an objective insight of the barriers to proliferation. In this paper, the Proliferation Resistance Analysis and Evaluation Tool for Observed Risk (PRAETOR), a multi-tiered analysis tool based on the multiplicative MAUA method, is presented. It folds sixty three mostly independent metrics over three levels of detail to give an ultimate metric for nonproliferation performance comparison. In order to reduce analysts' bias, the weighting between the various metrics was obtained by surveying a total of thirty three nonproliferation specialists and nonspecialists from fields such as particle physics, international policy, and industrial engineering. The PRAETOR was used to evaluate the Fast Breeder Reactor Fuel Cycle (FBRFC). The results obtained using these weights are compared against a uniform weight approach. Results are presented for five nuclear material diversion scenarios: four examples include a diversion attempt on various components of a PUREX fast reactor cycle and one scenario involves theft from a PUREX facility in a LWR cycle. The FBRFC was evaluated with uranium-plutonium fuel and a second time using thorium-uranium fuel. These diversion scenarios were tested with both uniform and expert weights, with and without safeguards in place. The numerical results corroborate nonproliferation truths and provide insight regarding fast reactor facilities' proliferation resistance in relation to known standards. Nuclear Nonproliferation Fast Reactors Proliferation Resistance Safeguards
2	Proliferation resistances of Generation IV recycling facilities for nuclear fuel Åberg Lindell, Matilda January 2013 (has links) The effects of global warming raise demands for reduced CO2 emissions, whereas at the same time the world’s need for energy increases. With the aim to resolve some of the difficulties facing today’s nuclear power, striving for safety, sustainability and waste minimization, a new generation of nuclear energy systems is being pursued: Generation IV. New reactor concepts and new nuclear facilities should be at least as resistant to diversion of nuclear material for weapons production, as were the previous ones. However, the emerging generation of nuclear power will give rise to new challenges to the international safeguards community, due to new and increased flows of nuclear material in the nuclear fuel cycle. Before a wide implementation of Generation IV nuclear power facilities takes place, there lies still an opportunity to formulate safeguards requirements for the next generation of nuclear energy systems. In this context, this thesis constitutes one contribution to the global efforts to make future nuclear energy systems increasingly resistant to nuclear material diversion attempts. This thesis comprises three papers, all of which concern safeguards and proliferation resistance in Generation IV nuclear energy systems and especially recycling facilities: In Paper I, proliferation resistances of three fuel cycles, comprising different reprocessing techniques, are investigated. The results highlight the importance of making group actinide extraction techniques commercial, due to the inherently less vulnerable isotopic and radiological properties of the materials in such processes. Paper II covers the schematic design and safeguards instrumentation of a Generation IV recycling facility. The identification of the safeguards needs of planned facilities can act as a guide towards the development of new instrumentation suitable for Generation IV nuclear energy systems. Finally, Paper III describes a mode of procedure for assessing proliferation resistance of a recycling facility for fast reactor fuel. The assessments may be used, as in this case, as an aid to maintain or increase the inherent proliferation resistance when performing facility design changes and upgrades. safeguards proliferation resistance Generation IV reprocessing
3	Proliferation resistance evaluation of CANDU reactor systems with different fuel cycles Wang, Xiaopan January 2016 (has links) In the process of exploring the thorium fuel application in CANDU reactors, it is important to consider the proliferation resistance level as a parameter for comparison with current natural uranium fuel. The concept of a whole fuel cycle was introduced to show the variations in the proliferation resistance level as the material is flowing through the cycle. The depletion and decay histories were simulated with SCALE 6.1 code and the results such as isotopes composition, decay heat, and radioactivity were used to analyze the material attractiveness of pure heavy metal for weapon production. They also served as the intrinsic features during the proliferation resistance level calculation. The Multi-Attribute Utility Analysis (MAUA) method developed by Chalton was used to compare different CANDU fuel cycles with quantified values (PR) from the viewpoint of proliferation resistance. To improve the biased MAUA results that gave a PR of 0.76 to CANDU while 0.93 to PWR, the attributes of size/weight and refueling scheme were reconsidered. In addition, the sensitive technology involved was added for the proliferation resistance recalculation. The results showed an increased PR value of 0.82 for natural uranium CANDU reactor as well as a decreasing trend of PR at the back end. PWR has a PR of 0.82 with revised MAUA method. The PR comparison of thorium and natural uranium fuel indicated that Th/Pu fuel has a slightly higher PR value in the reactor. The Figure of Merit (FOM) method developed by Bathke was used to validate the PR results from another perspective: the attractiveness of pure heavy metals that are suitable for nuclear weapon production. The results showed that FOM of plutonium keeps increasing with decay time and the trend becomes more significant after disposal in the deep geological repository. The FOM of uranium from Th/Pu cases is higher than that of Pu within several hundred years but maintains a decreasing trend. The decreasing FOM of uranium is preferred for direct disposal in deep geological repository. The decreased PR level and the increased FOM value of plutonium at the back end of a fuel cycle indicate the importance of implementing the security and safeguard for each facility dealing with nuclear materials. The comparison results of PR and FOM values for different fuel provided feedback and suggestions for the new fuel application. / Thesis / Master of Applied Science (MASc) proliferation resistance CANDU fuel cycle thorium application
4	Development of the fundamental attributes and inputs for proliferation resistance assessments of nuclear fuel cycles Giannangeli, Donald D. J., III 17 September 2007 (has links) Robust and reliable quantitative proliferation resistance assessment tools are critical to a strengthened nonproliferation regime and to the future deployment of nuclear fuel cycle technologies. Efforts to quantify proliferation resistance have thus far met with limited success due to the inherent subjectivity of the problem and interdependencies between attributes that contribute to proliferation resistance. This work focuses on the diversion of nuclear material by a state and defers other threats such as theft or terrorism to future work. A new approach is presented that assesses the problem through four stages of proliferation: the diversion of nuclear material, the transportation of nuclear material from an internationally safeguarded nuclear facility to an undeclared facility, the transformation of material into a weapons-usable metal, and weapon fabrication. A complete and concise set of intrinsic and extrinsic attributes of the nation, facility and material that could impede proliferation are identified. Quantifiable inputs for each of these attributes are defined. For example, the difficulty of handling the diverted material is captured with inputs like mass and bulk, radiation dose, heating rate and others. Aggregating these measurements into an overall value for proliferation resistance can be done in multiple ways based on well-developed decision theory. A preliminary aggregation scheme is provided along with results obtained from analyzing a small spent fuel reprocessing plant to demonstrate quantification of the attributes and inputs. This quantification effort shows that the majority of the inputs presented are relatively straightforward to work with while a few are not. These few difficult inputs will only be useful in special cases where the analyst has access to privileged, detailed or classified information. The stages, attributes and inputs of proliferation presented in this work provide a foundation for proliferation resistance assessments which may use multiple types of aggregation schemes. The overall results of these assessments are useful in comparing nuclear technologies and aiding decisions about development and deployment of that technology. nuclear nonproliferation nuclear security proliferation resistance nuclear power reprocessing uranium enrichment nuclear weapons nuclear terrorism
5	Performance and Safety Analysis of a Generic Small Modular Reactor Kitcher, Evans Damenortey, 1987- 14 March 2013 (has links) The high and ever growing demand for electricity coupled with environmental concerns and a worldwide desire to shed petroleum dependence, all point to a shift to utilization of renewable sources of energy. The under developed nature of truly renewable energy sources such as, wind and solar, along with their limitations on the areas of applicability and the energy output calls for a renaissance in nuclear energy. In this second nuclear era, deliberately small reactors are poised to play a major role with a number of Small Modular Reactors (SMRs) currently under development in the U.S. In this work, an SMR model of the Integral Pressurized Water Reactor (IPWR) type is created, analyzed and optimized to meet the publically available performance criteria of the mPower SMR from B&W. The Monte Carlo codes MCNP5/MCNPX are used to model the core. Fuel enrichment, core inventory, core size are all variables optimized to meet the set goals of core lifetime and fuel utilization (burnup). Vital core behavior characteristics such as delayed neutron fraction and reactivity coefficients are calculated and shown to be typical of larger PWR systems, which is necessary to ensure the inherent safety and to achieve rapid deployment of the reactor by leveraging the vast body of operational experience amassed with the larger commercial PWRs. Inherent safety of the model is analyzed with the results of an analytical single channel analysis showing promising behavior in terms of axial and radial fuel element temperature distributions, the critical heat flux, and the departure from nucleate boiling ratio. The new fleet of proposed SMRs is intended to have increased proliferation resistance (PR) compared to the existing fleet of operating commercial PWRs. To quantify this PR gain, a PR analysis is performed using the Proliferation Resistance Analysis and Evaluation Tool for Observed Risk (PRAETOR) code developed by the Nuclear Science and Security Policy Institute at Texas A&M University. The PRAETOR code uses multi-attribute utility analysis to combine 63 factors affecting the PR value of a facility into a single metric which is easily comparable. The analysis compared hypothetical spent fuel storage facilities for the SMR model spent fuel assembly and one for spent fuel from a Westinghouse AP1000. The results showed that from a fuel material standpoint, the SMR and AP1000 had effectively the same PR value. Unable to analyze security systems and methods employed at specific nuclear power plant sites, it is premature to conclude that the SMR plants will not indeed show increased PR as intended. Assessment Proliferation Resistance Single Channel Analysis Neutronics Analysis Water Reactor Integral Pressurized Small Modular Reactor
6	Safeguards for Uranium Extraction (UREX) +1a Process Feener, Jessica S. 2010 May 1900 (has links) As nuclear energy grows in the United States and around the world, the expansion of the nuclear fuel cycle is inevitable. All currently deployed commercial reprocessing plants are based on the Plutonium - Uranium Extraction (PUREX) process. However, this process is not implemented in the U.S. for a variety of reasons, one being that it is considered by some as a proliferation risk. The 2001 Nuclear Energy Policy report recommended that the U.S. "develop reprocessing and treatment technologies that are cleaner, more efficient, less waste-intensive, and more proliferation-resistant." The Uranium Extraction (UREX+) reprocessing technique has been developed to reach these goals. However, in order for UREX+ to be considered for commercial implementation, a safeguards approach is needed to show that a commercially sized UREX+ facility can be safeguarded to current international standards. A detailed safeguards approach for a UREX+1a reprocessing facility has been developed. The approach includes the use of nuclear material accountancy (MA), containment and surveillance (C/S) and solution monitoring (SM). Facility information was developed for a hypothesized UREX+1a plant with a throughput of 1000 Metric Tons Heavy Metal (MTHM) per year. Safeguard goals and safeguard measures to be implemented were established. Diversion and acquisition pathways were considered; however, the analysis focuses mainly on diversion paths. The detection systems used in the design have the ability to provide near real-time measurement of special fissionable material in feed, process and product streams. Advanced front-end techniques for the quantification of fissile material in spent nuclear fuel were also considered. The economic and operator costs of these systems were not considered. The analysis shows that the implementation of these techniques result in significant improvements in the ability of the safeguards system to achieve the objective of timely detection of the diversion of a significant quantity of nuclear material from the UREX+1a reprocessing facility and to provide deterrence against such diversion by early detection. nuclear material safeguards UREX UREX+1a Uranium Extraction proliferation resistant proliferation resistance reprocessing PUREX Plutonium Uranium IAEA TMFD Tension Metastable Fluid Detector detection probability nondetection probability non-detection probability nuclear material accountancy containment and surveillance solution monitoring process monitoring false alarm probability real-time measurement material balance area material balance period key measurement point significant quantity timely detection defense in depth detector non-destructive assay NDA front-end measurement material unaccounted for CCD-PEG TRUEX TALSPEAK

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