Sharif Digital Repository

Spent fuel assemblies are kept in spent fuel maintenance pools, designed at the vicinity of the reactor, after consuming. As capacity of these pools are limited, fuel assemblies should be transported to outside of the reactor building for maintenance. Transportation cask is used for this reason which is Russian type, named TUK-13, at Bushehr Nuclear Power Plant. The aim of this project is to ensure proper removal of heat from the transportation cask(TUK-13). For this purpose, numerical computational fluid dynamics method is used. The software used in this study is the Comsol. The temperature range suitable for any part of the chamber is different; but the most sensitive and the most... 

In order to identify the representative radioactive waste streams at Bushehr Nuclear Power Plant (BNPP) for use in Scaling Factor Determination Program for BNPP, all the relevant technical documents of BNPP including the Final Safety Assessment Report (FSAR) and Operation Manuals (OM) were carefully studied. In addition, the waste stream lines were closely examined by frequently visiting the plant and consulting with the responsible technical staff of BNPP.
As a result, twelve distinct waste streams (2 streams of concentrated waste, 3 streams of sludge, 1 stream of spent resin of TC31B001 tank, 1 stream of spent resin of UZ20B001 tank, 1 stream of selective sorbent TR41B001, 1 stream of... 

In this thesis, a Segmented Gama Scanning System for measuring total activity of the low/intermediate level radioactive waste drums is designed and a prototype 3-segmented commercial system is manufactured by using NaI detectors. The optimum distance of detector from drum surface and the optimum number of detectors on reconstruction of the radioactivity of the waste drum were studied by MCNP simulations. In addition, the effects of inhomogeneous distribution of radioactivity, the addition of lead filters to detectors, the change in collimator length and the asymmetrical placement of a drum on the rotary plate were also examined by the MCNP calculations. In the absence of a real radioactive... 

At a unit in zirconium production plant under the supervision of Soure Co. nuclear grade zirconium is produced. In the process it is required that hafnium get separated from Zirconium. Zirconium and hafnium separation are performed by nitric acid (4N) and hydrochloric acid (4N). This isolation environment is considerably corrosive and damaging for the equipment. Powder coating is one of the solutions to deal with the corrosion. To do so, electrostatic powder coating method was used for ECTFE polymer. After the coating, according to spark test, roughness analysis, thickness, elasticity and adhesion; temperature and time of the spraying and the spraying of top coating was determined. In... 

The raw and conditioned operational waste streams of Bushehr Nuclear Power Plant (BNPP) was determined by reviewing numerous plant’s documents (such as FSAR and operational documents) as well as by interviewing with persons in charge of BNPP waste management office. It was found that low/intermediate (type І and ІІ) level operational waste streams generated in BNPP is divided into eight independent streams. By using gamma emitting radionuclides as virtual DTM nuclides and determination of scaling factors for these nuclides, it was concluded that all the 8 waste streams can be grouped into one, that is, a universal scaling factor can be applied for all the 8 waste streams. In addition the... 

The Iranian Nuclear waste management Company is responsible for the safe disposal of the low-level radioactive waste resulting from the various processes of the nuclear fuel cycle and other radioactive-related activities. The safety assessment of waste disposal requires the measurement of transport parameters of radioactive nuclides in the soil around the disposal site.In this project, concentration profiles within a column which filled with Anarak Radioactive Waste Disposal Site soil were obtained using collimated gamma scanning method. Concentration profiles were measured at two different times (69 and 138 hours after injection). Then, using STANDMOD software, the equilibrium... 

The Iranian Nuclear waste management Company is responsible for the safe disposal of the low-level radioactive waste resulting from the various processes of nuclear fuel cycle and other radioactive-related activities. The safety assessment of waste disposal requires the measurement of transport parameters of radioactive nuclides in the soil around the disposal site. In this project, the transport parameters of cobalt nucleus in the Naeein disposal soil were measured using two static (batch) and dynamic (column experiment) methods. In the static method, the distribution coefficient was determined by performing batch adsorption experiments, and then the retardation factor for the soil disposal... 

Safety assessment of the final disposal of radioactive waste is crucial to ensure the waste isolation from the biosphere for long periods of time. There are various scenarios for the radionuclide transport from the disposal site to the environment, among which the ground water scenario is considered as the main scenario of the radionuclides migration. In this scenario, the transport parameters of the radionuclides are very important in the safety assessment of the final disposal of radioactive wastes. These parameters are determined using either dynamic or static methods, which usually the dynamic method leads to more realistic results. In the dynamic method, one of the two approaches of... 

In this thesis, a computer program is produced to measure the activity of 137Cs and 60Co radionuclides in waste packages generated at Bushehr Nuclear Power Plant (BNPP). In this program, the activity of waste drum was calculated by dividing the waste matrix into very small identical cubic cells, and each cell was considered as a point source (in the center of the cell). The activity was calculated using the theory developed by Krings & Mauerhofer. Detection efficiencies were calculated by the developed program at different conditions of a) different detector distance from drum surface, b) different collimator length, c) different cell size and d) up to 4 segment number. The results were... 

Beam diagnostics is an essential constituent of any accelerator. The position information of the electron beam is obtained by a set of Beam Position Monitors (BPMs), which in addition to determining the position, are used to derive information concerning lattice functions and beam dynamics. To design of Button Beam Position Monitor(BPM) for a Synchrotron Light Source, to get beam stabilities on submicron levels, preliminary studies were done to have optimal design. We present an algorithem which caculate all required parameteres for different design of button BPMs. To calculate induced charge and voltage on each button, Poisson's equation has been solved by Green method. For sensivity... 

During various stages of processing uranium in Isfahan’s UCF plant, liquid waste containing uranium compounds, is directed to evaporation lagoons. Gradually, a considerable amount of precipitation will form at the bottom of the lagoons. Since the concentration of uranium in evaporation ponds is relatively high, it seems that in addition to environmental issues, recycling uranium from existing pools is also economical. Uranium may be recovered from an aqueous solution by precipitation, solvent extraction and ion exchange. The solvent extraction is the best option for our purpose because of simple operation without increased consumption of heat or chemicals. It is also preferable when large... 

In Iran, the Iranian Nuclear Waste Management Company (INWMC) is responsible for safe disposal of low-level radioactive waste which results from different processes of nuclear fuel cycle and other radioactive-related activities. The safety assessment program is essential to ensure safe isolation of radioactive waste from the biosphere for long periods of time. Usually, the ground water scenario is considered as the main scenario of radionuclides migration from repository to the biological environment. Thus, it is required to measure the transport parameters of radionuclides in the porous media (soil) around the disposal site. In this research, laboratory scale columns, filled with Nain... 

Nuclear waste management in Iran is the responsibility of the Nuclear Waste Company. The waste company is obliged to bury waste with a certain level of radioactivity, resulting from various processes of the nuclear fuel cycle or other processes such as research projects and medical centers, after the necessary measures, finally at the Anarak landfill site. To evaluate the safety of the site, it is necessary to study the parameters of radioactive nucleation in the soil. Humic substances from natural substances in the soil affect the transport of radioactive nuclei. In this project, to study the effects of the presence of humic acid, the soil of Anarak residue in three weight percent... 

During production process in Uranium Conversion Facility (UCF) plant at Isfahan, the liquid waste containing uranium compounds, is directed to evaporation lagoons. Gradually, a considerable amount of precipitation will form at the bottom of these lagoons. Uranium concentration in this precipitation is very high and can range from tens of ppm to the order of a few weight percent. As such, it seems that uranium recovery from the UCF waste liquid is not only economically advantageous, but also effective for protecting the environment.The liquid waste resulting from the uranium extraction process contains a great amount of Fluoride ( ppm or higher) which cannot possibly be thrown away into... 

During the various stages of uranium processing in Uranium Conversion Facility (UCF) in Isfahan, significant amounts of liquid waste stream is produced which is sent to evaporation ponds. In addition to environmental considerations, uranium recovery from existing pools is also economically feasible due to high concentration uranium in liquid waste. Several methods have been evolved over the years to remove dissolved uranium from uranium bearing solution. These methods are: chemical precipitation, liquid-liquid extraction, ion exchange and membrane processes. The purpose of this study is recovery of uranium from liquid waste of Isfahan UCF plant by using ion exchange method. Although this... 

Magnetic resonance imaging is one of non-invasive methods to measure the hemodynamic and morphologic parameters of tissues, especially brain tissues. Hemodynamic parameters monitoring in brain tissue is of significant importance in many majors such as detection of tumor occurrence, brain abnormalities, and track of treatment procedures. Blood is a suspension, comprised of plasma, red blood cells, white blood cells, platelet, etc. Plasma is a Newtonian fluid which is composed of proteins and has a constant viscosity in body temperature. Rheological properties of blood are highly dependent on mechanical and rheological properties of its cells and this dependence is multiplied in narrow vessels... 

Uranium conversion process is one of the most important stages in nuclear fuel cycle. The Uranium Conversion Facilities (UFC) of Iran is located in Isfahan. In this plant, the Yellowcake (impure uranium oxide, U3O8) is converted to Uranium hexa-fluoride, UF6. During the process, considerable amounts of uranium-containing liquid waste are generated. This liquid waste was collected in evaporation pools inside the UCF Plant. In the course of time, a thick layer of precipitated salt form in bottom of the pools which are collected and stored in drums inside a building. This solid waste contains uranium at concentration levels much higher than that permitted for land disposal of the waste.... 

Steels as structural materials of pressure vessels of nuclear reactors, in addition to high temperatures and pressures, are exposed to ionizing radiation such as neutrons. The primary effects of damage caused by exposing these solids to radiation are the displacement of atoms from their equilibrium positions and the formation of point defects and damage clusters caused by damage accumulation due to displacement cascades produced by transmitting the energy of the incident particle to an atom by interactions such as elastic and inelastic scatterings neutrons with the nucleus. These microstructural changes cause large structural defects such as swelling, cracking, cracking, creep, reducing... 

I-131 isotope is one of the most significant radio medicines for treatments of the thyroid cancer and nuclear tomography of thyroid. As for purification of this radioisotope several methods have been developed among which adsorption-desorption on metallic copper is the most promising. The current study is aimed at elaboration of the kinetics behavior of the different types of metallic copper for adsorption of iodine vapor. The used copper samples included plain and silica-supported Cu nanoparticles as well as micronized copper. The silica-supported Cu nanoparticles were prepared by impregnation of highly porous silica (≈500 m2/g) in Cu(NO3)2 solution, heating of the solution to above... 

Uranium is one of the most important elements in nuclear fuel cycle. Recovery of uranium from wastes that were generated in varrious prosesses of nuclear fuel cycle, is very important not only because of economical values, but also due to their envirolmental. A considerable amount of solid waste have been produced during the fluorination process of in fluorination fludizedbed reactor at UCF plant in Iran. In this thesis, first, the solid waste of UCF floinatin reactor has been characterized. After characterization of waste, the dissolution of waste by different solvents has been studied and optimom condition for dissolution was determinated. Uranium recovery from the solution was tested...