BIANCA GERALDO
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Capítulo IPEN-doc 29463 Opening the Goiânia accident unburied waste packages2021 - TESSARO, ANA P.G.; GERALDO, BIANCA; SOUZA, DAIANE C.B. de; SMITH, RICARDO B.; VICENTE, ROBERTOThe year 2017 marks 30 years since the radiological accident in Goiânia, Brazil, which resulted from the leakage of Cs-137 from a teletherapy equipment. The contaminated material collected during the response to the accident was disposed of in Abadia de Goiás, about 20 km from Goiânia. However, in the initial 15-day period before the authorities were notified, contaminated paper bales and scrap metal were sold and transported to material recycling facilities in the State of São Paulo, one thousand kilometers away. These materials were later collected in steel boxes and drums, and stored in the intermediate waste storage facility of the Nuclear and Energy Research Institute - IPEN, in São Paulo. The objective of this paper is to describe the work performed to check the present condition of the paper bales waste boxes, reassess the reported Cs-137 activities, and evaluate possible treatment methods that can be applied to reduce the volume of waste. Prospective waste treatment methods are discussed.Livro IPEN-doc 28394 Essays on nuclear energy and radioactive waste management2021 - TESSARO, ANA P.G.; GERALDO, BIANCA; SOUZA, DAIANE C.B. de; ROMERO, FERNANDA; BISURI, INDRANIL; MARUMO, JULIO T.; CHEBERLE, LUAN T.V.; SACHDEVA, MAHIMA; ROSA, MYCHELLE M.L.; ROLINDO, NATALIE C.; SMITH, RICARDO B.; VICENTE, ROBERTO; SALVETTI, TEREZA C.Artigo IPEN-doc 27429 Radioanalytical methods for sequential analysis of actinide isotopes in activated carbon filter‑bed waste2020 - GERALDO, BIANCA; ARAUJO, LEANDRO G. de; VICENTE, ROBERTO; TADDEI, MARIA H.T.; CHEBERLE, SANDRA M.; MARUMO, JULIO T.In this work, we compare methods for the sequential determination of U and the transuranium elements Np, Pu, Am, and Cm. The chemical yield, the time spent in the analysis, the amount of secondary waste, and the costs of each method are the aspects of interest. Two methods were compared: extraction chromatography (EC) and ion exchange plus extraction chromatography (IE + EC). The chemical yields of (EC) and (IE + EC) were similar for all radionuclides. The (EC) method is the more effective with respect to time of analysis, the amount of secondary waste and costs.Resumo IPEN-doc 27082 Radiochemical methodology applied to determination of gamma emitting radionuclides in waste samples from IEA-R1 reactor2017 - GERALDO, BIANCA; VICENTE, ROBERTO; GOES, MARCOS M.; MARUMO, JULIO T.Artigo IPEN-doc 27080 Radiochemical method for characterization of the filter cartridges from the IEA-R1 reactor2016 - GERALDO, BIANCA; VICENTE, ROBERTO; FERREIRA, ROBSON J.; MADUAR, MARCELO F.; GOES, MARCOS M.; MARUMO, JULIO T.The filter cartridges used in water purification system of the IEA-R1 research reactor become radioactive waste after the end of their useful life. The characterization of this waste is one step in their management, which aims at identifying and quantifying the radionuclides present, including those known as "difficult to measure" (DTM) radionuclides. Wastes from nuclear reactors contain fission and activation products and transuranic elements, only few of them emitting gamma radiation measurable by simple gamma spectrometry methods. In routine waste management activities, the concentrations of the DTM can only be estimated by indirect methods such as scaling factors. The method of the scaling factors uses empirically determined proportions between the concentrations of DTM radionuclides and that of easily measurable gamma emitters called key nuclides (KN), to calculate DTM concentrations. Determining the scaling factors for the filter cartridges is a hard task when the number of samples is large, not only because the preparation of samples is difficult but also because the number of radionuclides to analyze is large. If it can be demonstrated that DTM and KN are both distributed evenly in the filters, less samples from each filter are necessary, reducing lab work. The aim of this paper is to present the results of the assessment of homogeneity along the filter cartridges by gamma spectrometry of chemically reduced samples. Five thin slices of five filters were burnt and the ashes quantitatively dissolved and the activity concentration of the solutions determined by gamma spectrometry.Artigo IPEN-doc 26681 Radiochemical characterization of spent filter cartridges from the primary circuit of a research reactor2019 - GERALDO, BIANCA; ARAUJO, LEANDRO G. de; TADDEI, MARIA H.T.; FERREIRA, MARCELO T.; MADUAR, MARCELO F.; VICENTE, ROBERTO; MARUMO, JULIO T.Radiochemical-based analyses have been used for the characterization of radioactive waste. Nevertheless, the determination of alpha, beta and gamma emitters by radiochemical analysis of spent cartridge filters from a swimming-pool type reactor has not been previously addressed. This work aims at identifying and quantifying the radionuclides present in this waste, including the difficult to measure radionuclides. The distribution of the radionuclides in the filter was investigated by the determination of gamma-emitting nuclides and the z-score of the measured activity concentrations. The results indicated that all the filters are homogeneous, meeting the homogeneity criteria recommended by the International Atomic Energy Agency.Tese IPEN-doc 25962 Caracterização radioisotópica dos filtros de purificação da água do circuito primário do reator IEA-R1, e efluentes líquidos eventualmente liberados, por meio de técnicas radioanalíticas de separação para a determinação dos radionuclídeos de difícil medição e fatores de escala2018 - GERALDO, BIANCATécnicas radioquímicas de separação têm sido comumente utilizadas para a caracterização de rejeitos radioativos. No entanto, a determinação de radionuclídeos emissores alfa, beta e gama por análise radioquímica, em amostras de filtro cartucho utilizado no processo de retratamento da água de um reator do tipo piscina, não foi abordada anteriormente na literatura. Este trabalho tem como objetivo estabelecer um método de solubilização para os filtros, identificar e quantificar os radionuclídeos presentes nestes rejeitos, sendo eles os Radionuclídeos Chaves (RC) (60Co, 108mAg, 110mAg) e principalmente os Radionuclídeos de Difícil Medição (RDM) (63Ni, 90Sr, 234U, 235U, 238U, 238Pu, 239+240Pu, 241Pu, 241Am, 242Cm e 243+244Cm), para posterior aplicação do método de Fator de Escala (FE) no trabalho rotineiro de caracterização de rejeitos radioativos. A distribuição dos radionuclídeos no filtro cartucho foi investigada pela determinação dos radionuclídeos emissores gama e os resultados obtidos foram utilizados para calcular o escore-Z. Os resultados indicaram que todos os filtros podem ser considerados homogêneos, atendendo aos critérios de homogeneidade recomendados pela Agência Internacional de Energia Atômica (AIEA), e com isso foi possível definir a quantidade de amostras representativas a serem analisadas. Foram determinados, a partir de dados analíticos, a correlação existente entre os RDMs e RCs selecionados e foram obtidos FEs para todos os RDMs, com exceção do 241Pu.Resumo IPEN-doc 24575 Eletronic response of photodiode coupled to a boron thin film2017 - COSTA, P.; COSTA, F.E.; RAELE, M.P.; ZAHN, G.; GERALDO, B.; VIEIRA JUNIOR, N.D.; SAMAD, R.E.; GENEZINI, F.A.A portable thermal neutron detector is proposed using a silicon photodiode coupled to a boron thin film. The aim of this work was to verify the effect in the electronic response of this specific photodiode due to boron deposition, since the direct deposition of boron in the semiconductor surface could affect its electrical properties specifically the p-type layer that affects directly the depletion region of the semiconductor reducing the neutron detector efficiency count. Three boron depositions with different thickness were performed in the photodiode (S3590-09) surface by pulsed laser deposition and the photodiode was characterized, before and after the deposition process, using a radioactive americium source. Energy spectra were used to verify the electronic response of the photodiode, due to the fact that it is possible to relate it to the photopeak pulse height and resolution. Spectra from the photodiode without and with boron film deposition were compared and a standard photodiode (S3590-04) that had the electronic signal conserved was used as reference to the pulse height for electronics adjustments. The photopeak energy resolution for the photodiode without boron layer was 10.26%. For the photodiode with boron deposition at different thicknesses, the resolution was: 7.64% (0.14 m), 7.30% (0.44 m) and 6.80% (0.63 m). From these results it is possible to evaluate that there was not any degradation in the silicon photodiode.Artigo IPEN-doc 24425 Radioactive waste management Goiânia - São Paulo: 30 years later2017 - SOUZA, D.C.B. de; GERALDO, B.; TESSARO, A.P.G.; ROSTELATO, M.E.C.M.; MARUMO, J.T.; CARVALHO, V.S.; BARBOSA, N.K.O.; VICENTE, R.Considered the largest urban radiological accident in the world, the accident in Goiânia with Cesium-137 resulted in the death of four people and injuries in another 49, besides measurable levels of internal or exter-nal contamination in 129. The accident generated also environmental contamination and thousands of tons of radioactive waste that resulted from the response activities. The accident occurred as a result of the disman-tling of an equipment of radiotherapy by employees of a junkyard. Before the accident was identified, con-taminated materials were sent to recycling companies in the state of São Paulo. The objective of this work was to report the existence of waste from Goiânia accident in the state of São Paulo and to check the estimat-ed activities at the time of the waste conditioning by measuring the current dose rates in waste packages, allowing a refinement of previously applied calculations.Artigo IPEN-doc 24424 Evaluation of Exhaust System for Gaseous Waste from the Source Production Laboratory for Radiotherapy – IPEN2017 - SOUZA, D.C.B. de; COSTA, O.L.; FEHER, A.; GERALDO, B.; CARVALHO, V.S.; BARBOSA, N.K.O.; VICENTE, R.; ZEITUNI, C.A.; ROSTELATO, M.E.C.M.Exhaust systems in fume hood for chemicals and hazardous materials as radioactive substances are of great importance for the protection of the Occupationally Exposed Individual and the environment. They protect against external contam-inations by particulate matter, volatile and against inhalation of radioactive gases. This work intends to evaluate the exhaustion system of the Laboratory of Production of Radioactive Sources at the Nuclear and Energy Research Institute (IPEN).