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Proposal for a radiation shielding study aiming the implantation of neutrons beam shutter in the J-9 radiation channel of the Argonauta reactor of the Nuclear Engineering Institute.
Get PDFArgonauta, the only nuclear research reactor situated in Rio de Janeiro, located at the Institute of Nuclear Engineering (IEN), regularly serves a network of users focused on research and development, and also provides its infrastructure for experimental classes and completion work course. Due to increasing demand for non-destructive thermal neutron assays and production of radioisotopes, there is a search for new procedures and/or devices that optimize users' exposure to neutrons. The implementation of mechanisms that allow access to the irradiation channels without the reactor being turned off and with a shielding configuration that limits the occupational doses at this location is very useful for the operation of the reactor. In order to achieve this, the present work proposes the establishment of a neutron beam shutter of the J-9 irradiation channel of the IEN’s Argonauta reactor. In a first step, experimental measurements were made in the irradiation channel of the reactor using a BF3 detector, which is coupled to a spectrometer. In this phase, the neutron beam was aligned to the spectrometer, and different materials were used as shields, aiming the attenuation of the beam. To validate and/or change the configuration of the barrier that best meets the material irradiation needs, a second planned phase is involving the neutron flux simulation of the reactor and the various shields with different boundary conditions using the particle transport code, Monte Carlo N-Particle Extended (MCNP- X)
Experimental device for obtaining calibration factor for the total count technique
Get PDFNuclear technologies have widely used on industry plants in order to help to solve troubles processes/design or just obtain information of them. The Total Count technique for flow measurement has as main advantages: being an absolute technique, because it is independent of additional devices readings unless the directly used for recording the radioactive cloud, requiring only a single detector to provide the final result; the independence of the internal volume of the transport duct, can be applied in the presence or absence of obstructions; no restriction as to the nature of the product or material to be conveyed; it is a noninvasive technique which allows real-time diagnostics. To use Total Count Technique, knowledge of a geometric calibration factor is required. Called Factor F, it is obtained in the laboratory using an experimental apparatus to faithfully reproduce the geometry of the detection system and the pipeline that being analyzed and using the same radiotracer, therefore, its value is constant for each specific measuring system under survey. This experimental apparatus for obtaining the factor F consisting by a pipe of 2 "PVC, which simulates a transmission line, where they were deposited 500 ml oil and the use of a specific pipette for use viscous fluids were added sequentially aliquots (50.00 ± 0.01) μl radiotracer (radionuclide photopeak energy of 198 Au 411.8 keV) and analyzing data obtained by three distinct detection systems composed of detectors NaI scintillators 1" x 1" and a data acquisition system
Use of transmission gamma for study of calculation of incrustation thickness in oil pipelines
Get PDFIncrustation can be defined as chemical compounds organic, inorganic and mixed, initially insoluble, and which precipitate accumulating in the internal wall of pipes, surface equipment and/or parts of components involved in the production and transport of oil. These compounds, when precipitating, cause problems in the oil industry and consequently result in losses in the optimization of the extraction process. Although the importance and impact of the precipitation of these compounds in the technological and economic scope, there is still the difficulty in determining methods that enable the identification and quantification of the incrustation at an initial stage. The use of the gamma transmission technique may provide support for a better understanding of the deposition of these compounds, making it a suitable tool for the non-invasive determination of their deposition in oil transport pipelines. The geometry used for the incrustation detection include a 280 mm diameter steel pipe containing barium sulphide incrustation (BaSO4) ranging from 5 to 80 mm, a gamma radiation source with divergent beam and as NaI(Tl) 2x2” scintillation detector. The opening size of the collimated beam was evaluated (2 to 7 mm) to also quantify the associated error in calculating the incrustation. The study was realized with computer simulation, using the MCNP-X code and validated by means of analytical equations that indicate the possibility of using this study for this purpose
Radiopharmaceutical shielding evaluation and dose rate estimate on the package of FDG produced by RDS-111 cyclotron at IEN
No full textIn this work the dose rates on the surface of and one meter far from a standard package of the radiopharmaceutical FDG (fluordeoxyglucose) produced by IEN's RDS111 cyclotron are estimated using two distinct methods: an anlaytic method and a Monte Carlo computer-based simulation method. The values obtained through both methods are then compared with experimental data. The results obtained are analyzed and interpreted, taking into account some features, such as: non-conformities in the measuring procedures, intrinsic errors of the radiation detectors, non-homogeneity of the shielding material, etc. This work is useful to evaluate and anticipate dose rates, as well as to optimize measuring, packing and expedition procedures in order to reduce doses and promote the implementation of ALARA principle
Simulation of fire in a deposit of radioactive waste and the radiological risk associated to this scenario
Get PDFA fire at radioactive waste deposit can result in significant damage as well as serious risks to the environment and the health of the general public. The CNEN (National Commission of Nuclear Energy) norms have fire protection regulations criteria and requirements to prevent the occurrence, neutralize the action and minimize the effects of the fire on the radioactive material present on the plant. These norms it is for to avoid or limit to the lowest possible levels the effects of ionizing radiation or toxic substances on humans and the environment. Before a possible fire containing radioactive material is necessary information that can estimate the dose in which the population will be submitted. In this work the proposal is to simulate a fire scenario containing radioactive material using Hotspot Health Physics simulation code and to identify the radiological risk of cancer in the respiratory system associated with this scenario using the BEIR V model
Fluid flow profile in a packed bead column using residence time curves and radiotracer techniques
Get PDFFilling columns are extremely important in the chemical industry and are used for purification, separation and treatment processes of gas or liquid mixtures. The objective of this work is to study the hydrodynamics of the fluid for a characterization of aqueous phase flow patterns in the filling column, associating with the methodology of the Curves of Residence Time Distribution (RTD) to analyze and associate theoretical models that put as conditions column operating. RTD can be obtained by using the pulse-stimulus response technique which is characterized by the instantaneous injection of a radiotracer into the system input. In this work, 68Ga was used as radiotracer. Five shielded and collimated NaI (Tl) 1x1" scintillator detectors were suitably positioned to record the movement of the radiotracer's path in the conveying line and filling column. Making possible the analysis of the RTD curve in the regions of interest. With the data generated by the NaI (Tl) detectors with the passage of the radiotracer in the transport line and inside the column, it was possible to evaluate the flow profile of the aqueous phase and to identify operational failures, such as internal conduit and the existence of a retention zone in the inside the column. Theoretical models were used for different flow flows: the piston flow and perfect mixing
Field dose radiation determination by active learning with gaussian process for autonomous robot guiding
Get PDFThis article proposes an approach for determination of radiation dose pro le in a radiation-susceptible
environment, aiming to guide an autonomous robot in acting on those environments, reducing the human
exposure to dangerous amount of dose. The approach consists of an active learning method based on
information entropy reduction, using log-normally warped Gaussian Process (GP) as surrogate model,
resulting in non-linear online regression with sequential measurements. Experiments with simulated
radiation dose elds of varying complexity were made, and results showed that the approach was e ective
in reconstruct the eld with high accuracy, through relatively few measurements. The technique was
also shown some robustness in presence measurement noise, present in real measurements, by assuming
Gaussian noise
Posicionamento em ambientes internos com dispositivos wi-fi de baixo custo
Get PDFO ritmo de desenvolvimento da pesquisa ligada ao rastreamento de localização está altamente vinculado com o avanço da rede de sensores sem fio e tecnologias sem fio, sendo explorado em muitas áreas. Um exemplo clássico é o Sistema de Posicionamento Global (GPS), onde satélites são usados para enviar sinais para receptores na Terra que usam estes sinais para computar informações de navegação. Entretanto, como a comunicação entre os satélites e receptores GPS exige a propagação de rádio em linha de visada, o sistema GPS geralmente só funciona em ambientes externos. Para o crescente interesse em pesquisas para rastreamento de posição em ambientes internos (indoor), é preciso utilizar dispositivos sem fio baseados em tecnologia Bluetooth ou Wi-Fi (IEEE 802.11). O objetivo deste trabalho é mostrar o desenvolvimento de aplicações utilizando novos dispositivos Wi-Fi (ESP8266) para a estimativa de posicionamento e localização em ambientes internos (indoor)
Avaliação dos critérios de quantificação de extintores de incêndio: reflexões sobre a aplicabilidade do critério da carga de incêndio
Get PDFThe quantification of the fire protection system for portable extinguishers, based on the legal and technician rules of the insurance agency, fire department and the ABNT (Brazilian Technician Standards Association), use extinguisher capacity and the extinguisher unit and apply on the isolated risks of the Brazilian Fire Tariff Insurance-TSIB, that in accordance with the three occupation class, are classified in risk class A (small risk), risk class B (average risk) and risk class C (great risk). This work has the objective to consider a reflection on the possibility of adoption of an alternative of extinguishers quantification system, that are based, independent of the place that has to protect, in the isolated fire load risk.A quantificação de extintores portáteis nas edificações toma como base as normas do órgão segurador, do corpo de bombeiros e da ABNT, cuja fundamentação técnica está na capacidade extintora e na unidade extintora dos extintores de incêndio aplicados aos riscos isolados constantes na Tarifa de Seguro Incêndio do Brasil – TSIB, que de acordo com as três classes de ocupação, são identificados em risco classe A (risco pequeno), classe B (risco médio) e classe C (risco grande). Este trabalho tem o objetivo de propor uma reflexão sobre a possibilidade de adoção de um sistema alternativo de quantificação de extintores, que se baseie, independente da utilização a que se destina o ambiente a proteger, na carga de incêndio específica do risco isolado
Projeto Memória-IEN: a fotografia contando os 40 anos de história do Instituto
Get PDFNo ano de 2002, por ocasião das comemorações do aniversário do Instituto de Engenharia Nuclear (IEN), foi montada a exposição itinerante “IEN - 40 Anos” que, em 2003, chegou ao Museu de Astronomia e Ciências Afins (MAST). Na solenidade de abertura foi feita a doação, para a guarda pelo MAST, do processo de criação do IEN e de um conjunto de instrumentos científicos que foram expostos. Também foi feito o
empréstimo de centenas de fotos P&B e coloridas que registravam desde o processo de criação do IEN até outros registros históricos importantes, ocorridos no período de seus primeiros 40 anos. O conjunto de fotos que conta parte da história do IEN, desde sua fundação até a década de 1990, retornou para o Instituto no final de 2013, sendo direcionado aos cuidados da biblioteca. Diante da necessidade de se encontrar uma
solução para a guarda do material, sem identificação e necessitando de higienização e organização, foi elaborado o Projeto Memória-IEN. A decisão sobre a preservação das fotos que retornaram foi de digitaliza-las para alimentar o repositório institucional (RI) CarpedIEN, que foi desenvolvido com a finalidade de armazenamento, preservação e disseminação do conhecimento produzido no Instituto. Considerando que essas fotos revelam muito sobre as atividades de pesquisas desenvolvidas no IEN, ações relacionadas à curadoria dessas imagens tomaram corpo ao ser desenvolvido o Projeto Memória-IEN, que visa preservar digitalmente este conjunto de fotos através do desenvolvimento de metodologia para curadoria de imagens digitais e do seu armazenamento no RI