Application of semi-empirical model for the evaluation of radium activity in phosphogypsum used as component of clinker
DOI:
https://doi.org/10.15392/bjrs.v9i1A.1518Keywords:
Phosphogypsum, Clinker, Activity, Radium, Semi-empirical modelAbstract
Phosphogypsum is a residue that has been used by the cement industry as a substitute for the natural gypsum, used as a clinker additive during the production of Portland cement. There is a potential increase in this residue use since the large amount of phosphogypsum is generated as outcome of the phosphate fertilizer industries. However, phosphogypsum can be considered a source of radioactive contamination since it has 226Ra in its composition. Depending on the concentration of 226Ra, from the radiological protection point of view, this may cause a problem because this radionuclide and its direct decay product 222Rn along with other decay products, represent the largest fraction of radiation internal dose received by people. In order to evaluate the level of radiological risk that may be associated with the use of phosphogypsum, it is necessary to identify the concentration of 226Ra in building material. The aim of this research is to analyze the samples of phosphogypsum in relation to the concentrations of 226Ra, determined indirectly through 222Rn activity measurements. This measurement process has the advantage of being fast, convenient and relatively inexpensive when compared to traditional 226Ra concentration in samples measurement methods. Proposed physical-mathematical model was used to establish radium concentration from radon exhalation rate from cement mortar samples. The 222Rn activity measurements were performed with a portable detector with cubic phosphate samples with 50 mm edges each placed in a closed atmosphere of the sampling chamber until secular equilibrium is achieved. Obtained concentrations of radium activity in studied samples of phosphogypsum and cement mortars were found below the limits recommended by CNEN and international regulation.
- Views: 199
- PDF Downloads: 130
Downloads
References
UNSCEAR – United Nations Scientific Committee on the Effects of Atomic Radiation. Sources and Effects of Ionizing Radiation, annex B, v. I, 2008. UNSCEAR Report to the United Nations General Assembly.
IAEA – International Atomic Energy Agency. The environmental behaviour of radium. Technical reports series n° 310. Vol.1. Vienna, 1990.
ATSDR – Agency for Toxic Substances and Disease Registry – US Department of Health and Human Services. Radon Toxicity. 2012. Disponível em: http://www.atsdr.cdc.gov/toxfaqs/tfacts145.pdf.
EISENBUD, M. Environmental radioactivity: from natural industrial and military sources. 3 ed. New York: Academic Press, Inc. 1987.
ICRP – International Commission on Radiological Protection. ICRP 60 - Recommendations of the international commission on radiological protection. Oxford: Pergamon Press, v.2, n.1-3, 1991.
CANUT, M.M.C. Estudo da viabilidade do uso do resíduo fosfogesso como material de construção. Dissertação de Mestrado. Programa de Pós-Graduação em Construção Civil – Universidade Federal de Minas Gerais, Belo Horizonte, 2006.
AQUINO, P.E. A Produção de Ácido Fosfórico e a Geração de Fosfogesso. In: Desafios Tecnológicos para o reaproveitamento do fosfogesso. Anais eletrônicos. Belo Horizonte. UFMG, 2005. Disponível em: http://www.fosfogesso.eng.ufmg.
SAUEIA, C.H.; MAZZILLI, B.P.; FAVARO, D.I.T. Natural radioactivity in phosphate rock, phosphogypsum and phosphate fertilizer in Brazil. Journal of Radioanalytical and Nuclear Chemistry, v. 264, p. 445-448, 2005.
RUTHERFORD, P.M.; DUDAS, M.J.; SAMEK, R.A. Environmental impacts of phosphogypsum. The Science Total Environmental, v. 149, p. 1-38, 1994.
SILVA, N.C.; FERNANDES, E.A.N.; CIPRIANI, M.; TADDEI, M.H.T. The natural radioactivity of Brazilian phosphogypsum. Journal Environmental Radioactivity, v. 249, p. 251-255, 2001.
MAZZILLI, B.; PALMIRO, V.; SAUEIA, C.H.R.; NISTI, M.B. Radiochemical characterization of brazilian phosphogypsum. Elsevier: Journal Environmental Radioactivity, n. 49, p. 113-122, 2000.
SANTOS, A.J.G.; SILVA, P.S.C.; MAZZILLI, B.P.; FAVARO, D.I. Radiological Characterization of disposed phosphogypsum in Brazil: Evaluation of the occupation exposure and environmental impact. Radiation Protection Dosimetry, v. 121, p. 179-185, 2006.
RUTHERFORD, P.M.; DUDAS, M.J.; SAMEK, R.A. Environmental impacts of phosphogypsum. The Science Total Environmental, v. 149, p. 1-38, 1994.
SAUEIA, C.H.R. Caracterização Radioquímica do Fosfogesso e implicações radiológicas de sua utilização como material de construção. Dissertação de Mestrado. Instituto de Pesquisas Energéticas e Nucleares, São Paulo, 1998.
PEREIRA, R.R. Incorporação do fosfogesso como substituto do gesso natural no processo de fabrico do cimento Portland. Dissertação de Mestrado. Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa, Lisboa, 2010.
BARRETO, R.C.; PERNA, A.F.N.; NARLOCH, D.C.; DEL CLARO, F.; CORRÊA, J.N.; PASCHUK, S.A. Determining Radium-226 Concentration From Radon-222 Emanation In Building Materials: A Theoretical Model. In: International Nuclear Atlantic Conference – INAC. Belo Horizonte, MG, Brazil, 2017.
SAPHYMO GmbH. The Reference in Professional Radon Measurement – AlphaGUARD. 2015. Manual do usuário, Saphymo. Disponível em: http://www.academia.edu/23518941/The_reference_in_professional_radon_measurement.
FERRY, C.; RICHON, P.; BENEITO, A.; CABRERA, J.; SABROUX, J.C. An experimental method for measuring the radon-222 emanation factor in rocks. Radiation Measurements, vol. 35, n°6, pp.579-583, 2002.
JANG, M.; KANG, C.S.; MOON, J.H. Estimation of radon-222 release from the phosphogypsum board used in housing panels. Journal of Environmental Radioactivity, vol.80, n°2, pp.153-160, 2005.
NAKAMURA, F.S.; BATISTA, A.C. Viabilidade Técnica da Utilização de Diferentes Proporções de Gesso e Fosfogesso como Material de Construção. Trabalho de Conclusão de Curso. Departamento Acadêmico de Construção Civil. Universidade Tecnológica Federal do Paraná, Curitiba, 2018.
Published
How to Cite
Issue
Section
License
Copyright (c) 2021 Brazilian Journal of Radiation Sciences
This work is licensed under a Creative Commons Attribution 4.0 International License.
Licensing: The BJRS articles are licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/