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Resultados preliminares no desenvolvimento de sistema para mapeamento remoto de radiação
Get PDFInstalações nucleares exigem monitoração continua da radiação ionizante no ambiente para fins de proteção
radiológica. Em alguns ambientes é desejável que essa monitoração não seja feita a partir de um monitor em
lugar fixo, considerando que esses materiais radioativos podem ser movidos de lugar, acrescentados ou
reagrupados no ambiente. Neste casos é comum que um trabalhador seja designado para fazer a monitoração do ambiente, carregando consigo o monitor de radiação para mapear o ambiente. Este trabalho apresenta o
desenvolvimento de um sistema para mapeamento remoto de radiação, com o objetivo de diminuir o tempo de
exposição de trabalhadores em instalações nucleares
Financial compensation due to municipalities that host radioactive waste deposits
Get PDFThis work aims to perform calculation about the financial compensation due to municipalities where there is viability for construction of radioactive waste deposits from low and medium activity. Were used like base structure de Resolution No. 96 of August, 10, 2010, entitled “Model of Calculation For Financial Compensation to Municipalities” where are determinate those principal characteristics by the waste and deposits, such as the half-life, activity level, type of deposits (initial, intermediate or final), costs for construction and maintenance of deposits, demography, between others. The calculation was made according to the temporally or definitive storage for solids waste like personal protection equipment (gloves, shoes, masks, etc) resins and filters used in wastewater treatment, between others, from of nuclear and radioactivity facilities. There are presented some countries that do the compensation, financial or not, for some municipalities for the construction of waste deposits and in some cases, the way that occurred the negotiation between the stakeholders, in other words, the local population and the companies. Also are presented others forms of financial compensation in Brazil in consequence of activities in large scale which result in potential risk for the surrounding population and for the environment, like compensation for oil and natural gas, hydropower plants and mining. Were used on methodology the inventory of waste presented on RMBN project (Repository of Waste of Low and Medium Activity) developed by the CDTN which present the implementation of a repository for final storage to radioactive waste. With this was possible to develop a case study with the creation of four scenarios. Values were found which initially range from R79,8 mil for month. Finally are analyzed the possible influences which that values may have on the municipality budget revenue and som
Gestão do conhecimento nuclear: preservação, disseminação e compartilhamento do conhecimento produzido no IEN
No full textDesenvolvimento de um código computacional 3-D para estudos de transferência de calor em varetas combustíveis, em situações não usuais
No full textEstudos de transferência de calor em varetas combustível são de grande importância na indústria nuclear. Isso se evidencia pela necessidade da predição de temperaturas limite para otimizar o projeto de varetas combustível. O presente trabalho tem por objetivo o desenvolvimento de um código computacional em linguagem fortran, no qual estão reunidas ferramentas como o Método de Elementos Finitos. Equações e correlações termo-hidráulicas foram implementadas no código com vistas a uma investigação profunda da transferência de calor entre a vareta combustível e o canal refrigerante, buscando, assim, entender o comportamento de ambos em regime transiente (como, por exemplo, nas situações de acidente). Foi feita uma análise sobre a validade da aproximação que desconsidera o fluxo axial de calor nas soluções analíticas. Comparações entre as soluções utilizando as propriedades constantes e propriedades dependentes da temperatura forma contempladas nesse trabalho. Estudos transientes envolvendo o desligamento do reator, considerando aspectos como a temperatura limite do combustível e o Departure from Nucleate Boiling Ratio (BNBR), foram realizados produzindo resultados que podem demonstrar o desempenho do código computacionalStudies on heat transfer fuel rods are of great importance in the nuclear industry . This is evidenced by the need for prediction of temperature limits to optimize the design of fuel rods . This work aims to develop a computer code in FORTRAN language, in which are gathered tools such as Finite Element Method . Equations and thermo- hydraulic correlations were implemented in the code with a view to a thorough investigation of heat transfer between the fuel rod and coolant channel , seeking thereby to understand the behavior of both in transient ( eg , in cases of accident ) . An analysis of the validity of the approach that disregards the axial heat flow in the analytical solutions was taken . Comparisons between solutions using constant properties and temperature dependent properties manner contemplated in this work . Transient studies involving the reactor shutdown , considering aspects such as limit the fuel temperature and Departure from nucleate Boiling Ratio ( BnBr ) , were performed yielding results that can demonstrate the performance of the computer cod
Experimental and numerical investigation of stratified gas-liquid flow in inclined circular pipes
No full textA methodology for macroscopic multigroup constants for accelerator driven system core calculation
No full textNumerical matlab routine evaluation of mass and heat of evaporation in an air-water surface interface
No full textStability of a Nanofiltration Membrane After Contact with a Low-Level Liquid Radioactive Waste
Get PDFThis study investigated the treatment of a liquid radioactive waste containing uranium (235U + 238U) using nanofiltration membranes. The membranes were immersed in the waste for 24–5000 h, and their transport properties were evaluated before and after the immersion. Surface of the membranes changed after immersion in the waste. The SW5000 h specimen lost its coating layer of polyvinyl alcohol, and its rejection of sulfate ions and uranium decreased by about 35% and 30%, respectively. After immersion in the waste, the polyamide selective layer of the membranes became less thermally stable than that before immersion