ANTONIO CARLOS IGLESIAS RODRIGUES

ANTONIO CARLOS IGLESIAS RODRIGUES

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Analysis and construction of the high density storage racks for spent fuel of the research reactor IEA-R1
2018 - RODRIGUES, ANTONIO C.I.; MADI FILHO, TUFIC; SILVA, DAVILSON G. da
The IEA-R1 research reactor works 40h weekly, with 4.5 Mw power. The storage rack for spent fuel elements has less than half of its initial capacity. Under these conditions, the reactor operating for 32h/week will have 3 spent fuel by year, approximately 3 utilization rate Positions/year; thus, we will have only about six years of capacity for storage. Since the desired service life of the IEA-R1 is at least another 20 years, it will be necessary to increase the storage capacity of spent fuel by doubling the wet storage in the reactor’s pool. 3M’s neutron absorber BoralcanTM was chosen after reviewing the literature about available materials for the construction of a new storage rack. This work presents studies for the construction of new storage racks with double of capacity using the same place of the current ones. Criticality safety analysis was performed with MCNP-5 Monte Carlo code, using two Evaluated Nuclear Data Files (ENDF/B-VI and ENDF/B-VII) in calculations, and subsequently, the results were compared. The full charge of the storage rack with only new fuel elements (maximum reactivity) was considered to calculate the keff. The results obtained in the simulations show that it is possible doubling the storage capacity of the spent fuel elements. Additionally, it complies with safety limits established by International Atomic Energy Agency (IAEA) and Brazilian Commission of Nuclear Energy (CNEN) standards to the criticality criteria (keff <0.95). This is only possible with the use of neutron absorber material.
Analysis and project of the high density storage racks for spent fuel of the research reactor IEA-R1
2018 - RODRIGUES, ANTONIO C.I.; MADI FILHO, TUFIC; SILVA, DAVILSON G. da
The IEA-R1 research reactor works 40h weekly with 4.5 Mw power. The storage rack for spent fuel elements has less than half of its initial capacity. Under these conditions (current conditions of reactor operation 32h weekly will have 3 spend fuel by year, then, approximately 3 utilization rate Positions/year). Thus, we will have only about six years of capacity for storage. Whereas the desired service life of the IEA-R1 is at least another 20 years, it will be necessary to increase the storage capacity of spent fuel. Hence, it is necessary to double the wet storage capacity (storage in the IEA-R1 reactor’s pool). After reviewing the literature about materials available for use in the construction of the new storage rack with absorber of neutrons, the BoralcanTM (manufactured by 3M) was chosen, due to its properties. This work presents studies: (a) for the construction of new storages racks with double of the current capacity using the same place of current storages racks and (b) criticality analysis using the MCNP-5 code. Two American Nuclear Data Libraries were used: ENDF / B-VI and ENDF / B-VII, and the results obtained for each data bases were compared. These analyzes confirm the possibility of doubling the storage capacity of fuel elements burned in the same place occupied by the current storage rack attending to the IEA-R1 reactor needs and attending the safety requirements according to the National Nuclear Energy Commission – CNEN and the International Atomic Energy Agency (IAEA). To calculate the keff new fuel elements (maximum possible reactivity) used in full charge of the storage rack were considered. With the results obtained in the simulation we can conclude that doubling the amount of racks for spent fuel elements are complied with safety limits established in the IAEA standards and CNEN of criticality (keff <0.95). It is mandatory to use neutron absorber material.
Core modeling of the research reactor IEA-R1 with the MCNP-6.2 computational code
2019 - RODRIGUES, ANTONIO C.I.; MADI FILHO, TUFIC; SILVA, DAVILSON G. da
The objective of this work is to develop the modeling of the IEA-R1 reactor core with the MCNP-6.2 computational code that was recently acquired. The main advantage of this new version of the code is the performance of burnup calculations of the fuel elements. This modeling will be valid by comparing the thermal and epithermal neutron flux obtained in the calculations with the MCNP-6.2 and the fluxes measured with the activation of gold foils (Au) with and without cadmium coating (Cd) in the same positions of irradiation and, with the same arrangement of fuel elements in the reactor core. After the validation of this model, the idea is to use it for the burnup calculations of the fuel elements that are fundamental for a correct management of the reactor core. Currently, the management of the core is carried out by deterministic codes that are very old and have many approximations leading to very conservative results, for example, TWODB, HAMMER, and CITATION.
Response of CsI:Pb scintillator crystal to neutron radiation
2018 - PEREIRA, MARIA da C.C.; MADI FILHO, TUFIC; BERRETTA, JOSE R.; CARDENAS, JOSE P.N.; RODRIGUES, ANTONIO C.I.
The helium-3 world crisis requires a development of new methods of neutron detection to replace commonly used 3He proportional counters. In the past decades, great effort was made to developed efficient and fast scintillators to detect radiation. The inorganic scintillator may be an alternative. Inorganic scintillators with much higher density should be selected for optimal neutron detection efficiency taking into consideration the relevant reactions leading to light emission. These detectors should, then, be carefully characterized both experimentally and by means of advanced simulation code. Ideally, the detector should have the capability to separate neutron and gamma induced events either by amplitude or through pulse shape differences. As neutron sources also generate gamma radiation, which can interfere with the measurement, it is necessary that the detector be able to discriminate the presence of such radiation. Considerable progress has been achieved to develop new inorganic scintillators, in particular increasing the light output and decreasing the decay time by optimized doping. Crystals may be found to suit neutron detection. In this report, we will present the results of the study of lead doped cesium iodide crystals (CsI:Pb) grown in our laboratory, using the vertical Bridgman technique. The concentration of the lead doping element (Pb) was studied in the range 5x10-4 M to 10-2 M . The crystals grown were subjected to annealing (heat treatment). In this procedure, vacuum of 10-6 mbar and continuous temperature of 350°C, for 24 hours, were employed. In response to neutron radiation, an AmBe source with energy range of 1 MeV to 12 MeV was used. The activity of the AmBe source was 1Ci Am. The fluency was 2.6 x 106 neutrons/second. The operating voltage of the photomultiplier tube was 1700 V; the accumulation time in the counting process was 600 s and 1800 s. The scintillator crystals used were cut with dimensions of 20 mm diameter and 10 mm height.
Study and project of the new rack with boron for storage of fuel elements burned in the IEA-R1 research reactor
2017 - RODRIGUES, ANTONIO C.I.; MADI FILHO, TUFIC; SILVA, DAVILSON G. da
The IEA-R1 research reactor works 40h weekly with 4.5 Mw power. The storage rack for spent fuel elements has less than half of its initial capacity. Under these conditions (current conditions of reactor operation 32h weekly will have 3 spend fuel by year, then, approximately 3 utilization rate Positions/year). Thus, we will have only about six years of capacity for storage. Whereas the desired service life of the IEA-R1 is at least another 20 years, it will be necessary to increase the storage capacity of spent fuel. Hence, it is necessary to double the wet storage capacity (storage in the IEA-R1 reactor's pool). After reviewing the literature about materials available for use in the construction of the new storage rack with absorber of neutrons, the BoralcanTM (manufactured by 3TMhis) wwaosr kc hporseesne,n dtsu es ttuod iitess :p r(oap) efrotrie tsh. e construction of new storages racks with double of the current capacity using the same place of current storages racks and (b) criticality analysis using the MCNP-5 code. Two American Nuclear Data Library were used: ENDF / B-VI and ENDF / B-VII, and the results obtained for each data bases were compared. These analyzes confirm the possibility of doubling the storage capacity of fuel elements burned in the same place occupied by the current storage rack attending to the IEA-R1 reactor needs and attending the safety requirements according to the National Nuclear Energy Commission - CNEN and the International Atomic Energy Agency (IAEA). To calculate the keff were considered new fuel elements (maximum possible reactivity) used in full charge of the storage rack. With the results obtained in the simulation we can conclude that doubling the amount of racks for spent fuel elements are complied with safety limits established in the IAEA standards and CNEN of criticality (keff < 0.95).
Estudo e projeto de novos cestos com boro para o armazenamento de elementos combustíveis queimados do reator IEA-R1
2016 - RODRIGUES, ANTONIO C.I.
O reator de pesquisas IEA-R1 opera em regime de 40 h semanais à potência de 4,5 MW. Nestas condições, os cestos disponíveis para o armazenamento dos elementos combustíveis irradiados possuem menos de metade da sua capacidade inicial. Assim, nestas condições de operação, teremos apenas cerca de seis anos de capacidade para armazenamento. Considerando que a vida útil desejada do IEA-R1 seja de pelo menos mais 20 anos, será necessário aumentar a capacidade de armazenamento de combustível irradiado. Dr. Henrik Grahn, especialista da Agência Internacional de Energia Atômica sobre o armazenamento molhado (em piscinas de estocagem), ao visitar o reator IEA-R1 (setembro/2012) fez algumas recomendações. Entre elas, a concepção e instalação de cestos fabricados com aço inoxidável borado e internamente revestidos com uma película de alumínio, de modo que a corrosão dos elementos combustíveis não ocorresse. Após uma revisão da literatura sobre opções de materiais disponíveis para esse tipo de aplicação chegamos ao BoralcanTM fabricado pela 3M devido suas propriedades. Este trabalho apresenta estudos sobre a análise de criticalidade com o código computacional MCNP-5 utilizando duas bibliotecas americanas de dados nucleares avaliados (ENDF/B-VI e ENDF/B-VII) comparativamente. Estas análises demonstraram a possibilidade de dobrar a capacidade de armazenamento de elementos combustíveis, no mesmo espaço ocupado pelos cestos atuais, atendendo a demanda do reator de pesquisas IEA-R1 e também satisfazendo os requisitos de segurança da Comissão Nacional de Energia Nuclear (CNEN) e da Agência Internacional de Energia Atômica (IAEA).
Design of a new wet storage rack for spent fuels from IEA-R1 reactor
2015 - RODRIGUES, ANTONIO C.I.; MADI FILHO, TUFIC; SIQUEIRA, PAULO T.D.; RICCI FILHO, WALTER
Borated stainless steel storage project to the spent fuel of the IEA-R1 reactor
2013 - RODRIGUES, ANTONIO C.I.; MADI FILHO, TUFIC; RICCI FILHO, WALTER
Application of prompt gamma source for n-16 detector system calibration
2011 - MADI FILHO, TUFIC; NAHUEL CARDENAS, JOSE P.; RODRIGUES, ANTONIO C.I.
Simulacao dos acidentes de partida a frio e queda de um elemento combustivel no reator IEA-R1m
1999 - RODRIGUES, A.C.I.; TEIXEIRA e SILVA, A.; CABRAL, E.L.L.; MESQUITA, R.N.; CONTI, T.N.