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Spent nuclear fuel is received at a storage facility in heavily shielded casks transported by either rail or by truck. Once at the storage facility, the casks are inspected, emptied, decontaminated, and reshipped. Allied-General Nuclear Services' (AGNS) nuclear fuel reprocessing plant in Barnwell, South Carolina, is constructed but not yet licensed for spent nuclear fuel storage or reprocessing. Recently, however, AGNS was granted funds by the Department of Energy to prepare the necessary procedural and regulatory paperwork in order that the Fuel Receiving and Storage Station (FRSS) of the plant can be licensed by 1985. In this paper, the activities involved in the receiving an unloading of casks at the Barnwell FRSS is simulated by computer using IBM's program software package, General Purpose Simulation System (GPSS). The GPSS model is developed and verified, and steady-state output statistics are achieved. Also, several sensitivity analyses are performed such as, changes in expected arrival schedules and decision policies, and changes to the physical characteristics of the existing FRSS to monitor the effect of these changes in the existing system.

A generalized multiple-objective research and development (R & D) capital budgeting model incorporating production-allocation decisions is developed for the analysis of the spent-nuclear-fuel management problem. The generalized model is decomposed into two subproblems. First is a multiple-objective R&D capital budgeting problem and second is a multiple-objective fuel allocation problem. Goal programming is selected as an appropriate modeling technique for both generic models. The spent-nuclear-fuel-allocation problem is further decomposed into a dynamic program with a goal program at each stage. The objectives are to allocate R&D funds to process or technology development and to allocate spent fuel to certain alternatives so as to minimize the weighted and prioritized vector cost. With regard to the objectives of non-proliferation and non-diversion, occupational and population exposure, uranium resource conservation, and fuel cycle economics. the major conclusion is to use the spent fuel for further energy production, preferably via a combination of extended burnup and recycle alternatives. / Ph. D.

Theoretial calculations of critical mass, temperature coefficient, and transient behavior have been made for proposed uranium dioxide and urania-thoria fuel cores for the Virginia Polytechnic Institute UTR-10 Reactor. / Master of Science

The need to extend light water reactor spent-fuel on-site storage requirements and the future need to relieve resulting stockpiles necessitates the determination of optimal spent-fuel-withdrawal patterns under various end-use scenarios. End-use scenarios include no-economic- return throwaway and uranium recycle with and without plutonium recycle. Results from developing, analyzing, and solving a spent-fuel-withdrawal model are used to recommend specific strategies. The spent-fuel-withdrawal problem involves the interaction of spent-fuel generation, time and capacity-dependent reprocessing demand, and expected spent-fuel value. Spent-fuel characteristics based upon burnup history and initial composition, are considered along with uranium, separative work, and storage cost projections to realize profitable spent-fuel disposition. Application of the spent-fuel-withdrawal model is done on a per-reactor basis. Assumptions inherent in the application of the model developed include, 1) unconstrained on-site storage capacity, 2) realizable uranium and plutonium values, and 3) capacity constrained reprocessing demand. Examining supply, demand, and characteristics of spent-fuel during a twenty-year horizon, the model application is developed through, 1) a dynamic programming approach, 2) a Hitchcock problem to be solved similarly to a minimum-cost-flow problem, and 3) a linear program definable as a Transportation problem. In the model analyses, the dynamic programming formulation proved to be computationally infeasible. The analyses of the Hitchcock and linear program problem is done by the use of the Out-Of-Kilter Algorithm and the proprietary mathematical MPS-III system, respectfully. Specific results indicate that the economically optimal withdrawal pattern is: 1) for uranium and plutonium recycle, a Last-In-First-Out pattern, and 2) for uranium recycle only, no discernible pattern. / Master of Science

The goal of this research was to identify and fabricate zeolitic membranes that can separate radioisotope krypton-85 (half-life 10.72 years) and xenon gas released during spent nuclear fuel reprocessing. In spent nuclear fuel reprocessing, fissionable plutonium and uranium are recovered from spent nuclear fuel and recycled. During the process, krypton-85 and xenon are released from the spent nuclear fuel as process off-gas. The off-gas also contains NO, NO2, 129I, 85Kr, 14CO2, tritium (as 3H2O), and air and is usually vented to the atmosphere as waste without removing many of the radioactive components, such as 85Kr. Currently, the US does not reprocess spent nuclear fuel. However, as a member of the International Framework for Nuclear Energy Cooperation (IFNEC, formerly the Global Nuclear Energy Partnership), the United States has partnered with the international nuclear community to develop a “closed” nuclear fuel cycle that efficiently recycles all used nuclear fuel and safely disposes all radioactive waste byproducts. This research supports this initiative through the development of zeolitic membranes that can separate 85Kr from nuclear reprocessing off-gas for capture and long-term storage as nuclear waste. The implementation of an 85Kr/Xe separation step in the nuclear fuel cycle yields two main advantages. The primary advantage is reducing the volume of 85Kr contaminated gas that must be stored as radioactive waste. A secondary advantage is possible revenue generated from the sale of purified Xe. This research proposed to use a zeolitic membrane-based separation because of their molecular sieving properties, resistance to radiation degradation, and lower energy requirements compared to distillation-based separations. Currently, the only commercial process used to separate Kr and Xe is cryogenic distillation. However, cryogenic distillation is very energy intensive because the boiling points of Kr and Xe are -153 °C and -108 °C, respectively. The 85Kr/Xe separation step was envisioned to run as a continuous cross-flow filtration process (at room temperature using a transmembrane pressure of about 1 bar) with a zeolite membrane separating krypton-85 into the filtrate stream and concentrating xenon into the retentate stream. To measure process feasibility, zeolite membranes were synthesized on porous α-alumina support discs and permeation tested in dead-end filtration mode to measure single-gas permeance and selectivity of CO2, CH4, N2, H2, He, Ar, Xe, Kr, and SF6. Since the kinetic diameter of krypton is 3.6 Å and xenon is 3.96 Å, zeolites SAPO-34 (pore size 3.8 Å) and DDR (pore size 3.6 Å) were studied because their pore sizes are between or equal to the kinetic diameters of krypton and xenon; therefore, Kr and Xe could be separated by size-exclusion. Also, zeolite MFI (average pore size 5.5 Å) permeance and selectivity were evaluated to produce a baseline for comparison, and amorphous carbon membranes (pore size < 5 Å) were evaluated for Kr/Xe separation as well. After permeation testing, MFI, DDR, and amorphous carbon membranes did not separate Kr and Xe with high selectivity and high Kr permeance. However, SAPO-34 zeolite membranes were able to separate Kr and Xe with an average Kr/Xe ideal selectivity of 11.8 and an average Kr permeance of 19.4 GPU at ambient temperature and a 1 atm feed pressure. Also, an analysis of the SAPO-34 membrane defect permeance determined that the average Kr/Xe selectivity decreased by 53% at room temperature due to unselective defect permeance by Knudsen diffusion. However, sealing the membrane defects with polydimethylsiloxane increased Kr/Xe selectivity by 32.8% to 16.2 and retained a high Kr membrane permeance of 10.2 GPU at ambient temperature. Overall, this research has shown that high quality SAPO-34 membranes can be consistently fabricated to achieve a Kr/Xe ideal selectivity >10 and Kr permeance >10 GPU at ambient temperature and 1 atm feed pressure. Furthermore, a scale-up analysis based on the experimental results determined that a cross-flow SAPO-34 membrane with a Kr/Xe selectivity of 11.8 and an area of 4.2 m2 would recover 99.5% of the Kr from a 1 L/min feed stream containing 0.09% Kr and 0.91% Xe at ambient temperature and 1 atm feed pressure. Also, the membrane would produce a retentate stream containing 99.9% Xe. Based on the SAPO-34 membrane analysis results, further research is warranted to develop SAPO-34 membranes for separating 85Kr and Xe.

The Reverse Osmosis (RO) process has been considered to be one of the most widely utilised techniques for brackish water desalination for its capabilities to produce high-quality water. The RO process characterised by its low energy consumption compared to thermal distillation processes, leading to reduced overall water production cost. To systematically understand the transport phenomena of solvent and solutes via the membrane texture, several mathematical models were developed. This interestingly aids to conduct a huge amount of simulation and optimisation studies to judge the influence of control variables on the performance indexes and to adjust the key variables at optimum values to realise optimum production indexes. In this research, a specific accurate model for a single spiral wound RO process has been successfully developed and used to build accurate models for the multistage brackish water RO desalination process of two different designs. The robustness of the model developed was confirmed via validation against the experimental data collected from simple design of RO system and complicated design of RO system of Arab Potash Company (APC). This is followed by a thorough simulation of the RO process to explore the influence of operating conditions on the process performance indicators. Recently, several contributions were made in this thesis that specifically comprises the improvement of the original design of brackish water RO desalination process. The influence of a retentate recycle design is investigated on the process performance. Moreover, evaluation and minimisation of specific energy consumption (expressed in kWh/m3 of freshwater production) is carried out on the simple and complicated designs of RO process by implementing an energy recovery device. Also, the most suitable brand of membranes was explored for the RO system from a set of different brands of membrane to attain the highest-performance rejection at lowest energy consumption compared to the original membrane. Furthermore, a single optimisation framework was developed to mitigate the specific energy consumption of simple and complicated designs of brackish water RO desalination process. Finally, a thermodynamic limitations and exergy analysis of the complicated design of RO system are outlined via a thoroughly study to investigate the locations of high exergy destruction. These contributions were verified as they promoted the separation performance at a significant energy saving. / Mutah University, Jordan

Thesis (MEdPsych)--University of Stellenbosch, 2005. / ENGLISH ABSTRACT: As I engaged in a therapy journey with a single client, the possibilities for research on the integrative use of narrative therapy and EMDR unfolded. I investigated recent literature and realised that much had been written about narrative therapy as single approach to therapy within the postmodern paradigm. There was also extensive writing on EMDR and its integrative use with other therapies in assisting people who struggle with upsetting memories of trauma. Since I was unable to find any literature to date on the integrative use of narrative therapy and EMDR, I realized that there was much to be discovered and learned on such an integrative research journey. The client's experiences and descriptions of overwhelming emotional distress (as the problem in her life) during the process of integration was the main focus of this qualitative case study. During our therapy conversations knowledges were gathered and deconstructed. Video or tape recordings, photographs, work with clay, sketches, letters and other documents were useful in keeping track of the research journey. A reflecting team and the participation of the client's boyfriend contributed and enriched both the therapy and research journeys. / AFRIKAANSE OPSOMMING: Tydens terapeutiese werk met 'n enkele kliënt het die moontlikhede van navorsing oor die integrasie van narratiewe terapie en EMDR vir my 'n werklikheid geword. Ek het onlangse navorsing bestudeer en besef dat narratiewe terapie as 'n enkele benadering tot terapie binne die post-moderne paradigma, al 'n geruime tyd lank nagevors is. Daar bestaan ook literatuur oor EMDR en die integrasie daarvan met ander terapeutiese benaderings in die ondersteuning van persone wat probleme ondervind met ontstellende herinnerings van trauma. Aangesien ek tot op hede geen literatuur oor die integrasie van narratiewe terapie en EMDR kon vind nie, het ek vermoed dat 'n navorsingsreis op hierdie terrein verskeie ontdekkings en die ontginning van nuwe kennis moontlik sou maak. Die fokus van hierdie kwalitatiewe gevallestudie val op die kliënt se belewing en beskrywings van oorweldigende emosies (as probleem in haar lewe) tydens die terapeutiese integrasieproses. Waarhede of kennis is tydens terapiegesprekke versamel en gedekonstrueer. Video- of bandopnames, foto's, kleiwerk, sketse, briewe en ander dokumente was waardevol om die koers van die navorsingsreis aan te dui. Insette en deelname van 'n refekterende span, asook die kliënt se kêrel, het beide die terapie- en navorsingsreise verryk en uitgebrei.

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The plastics industry is one of the fastest growing major industries in the world. There is an increase in the amount of plastic used for all types of products due to its light weight and ability to reprocess. For this reason, the reprocessing of thermoplastics and the usability of reprocessed materials are gaining significance, and it is important to produce and consume plastic materials in an environmentally friendly way. In addition, rising raw material cost linked to the increased oil prices encouraged for reusing of the plastic materials. The aim of this research was to study and optimize the injection moulding process parameters to achieve a trade-off between the product cost and product quality, measured through mechanical properties and geometry, based on using regrind ratios. The work was underpinned by a comprehensive study of multiple reprocessing effects in order to evaluate the effect of process parameters, material behaviour, reprocessing effects and possible links between the processing parameters and key properties. Experimental investigations were carried out, in particular, focused on the melt preparation phase to identify key process parameters and settings. Multiple reprocessing stages were carried out; using two types of PP material: unfilled and short glass filled. A series of tests were used to examine product quality (mass, colour and shrinkage) and physical properties (density, crystallinity, thermal stability, fibre length, molecular weight, in-line and off-line viscosity, tensile strength, modulus of elasticity, elongation (%) and flexural strength). This investigation showed that the mouldability of the filled and unfilled PP materials, through the successive reprocessing stages (using 100 % regrind), was observed to be relatively consistent. Given the link between the processing parameters and key product and material properties, it is possible to manufacture products with minimal loss to part quality and mechanical properties. The final phase of the work focused on process optimisation study for short glass fibre filled PP material and the identified key process parameters (melt temperature, screw rotational speed, holding pressure, holding time and injection rate). A response surface experiment was planned and carried out for three reprocessing stages (0 %, 25 % and 50 % regrind). The fitted response surface models were utilised to carry out the trade-off analysis between the operating cost (material cost, energy cost and labour cost) and product quality (dimensions and tensile strength) Based on the optimal moulding conditions, the operating cost was reduced (from stage I as a reference), by 24% and 30 % for stage II and stage III respectively. A small, perhaps undetectable, change in product dimensions was noted. In addition, a small reduction in tensile strength was noted (from stage I as a reference), by 0.4% and 0.1 % for stage II and stage III respectively. The same data was applied in other countries (Australia, USA, Brazil, Libya and China) to manufacture the same product; and it was observed that the cost was reduced with increasing of regrind ratio. But the significant reduction of the cost, essentially, depended on those countries which have low wage rates (e.g. Brazil, Libya and China). For example, the cost of moulded product manufactured in China is £ 0.025 (using 50% of regrind), while the cost of the same product produced in Australia is £ 0.12, hence giving a total saving of 79 % and making it a valuable issue to be considered in industry.