Back
 JEP  Vol.2 No.2 , April 2011
Radiochemical Characterization of Phosphogypsum for Engineering Use
Hanan Tayibi, Catalina Gascó, Nuria Navarro, Aurora López-Delgado, Mohamed Choura, Francisco J. Alguacil, Félix A. López
Abstract: The new phosphogypsum (PG) waste management policy allowed to reduce the negative environmental impact of this residue by finding better alternatives uses with an extremely limited radiological impact. Building material could be one of these alternatives that could lead to the production of final products with good mechanical properties and very limited radionuclides content. The optimization of the radioactive levels in the building materials when PG is used for its production requires the previous knowledge of the content of naturally occurring radionuclides in the PG waste. This article aims the radioactive characterization of two different PG sources (from Spain (Fertiberia S.A., Huelva) and Tunisia (Sfax), before being incorporated in building materials. For this purpose, the natural selected radionuclides content belonging to uranium and thorium decay series and 40K was determined, by means of two different methods: i) gamma spectrometry with high-purity germanium detectors and ii) laser-induced kinetic phosphorimetry (KPA-11 Chemcheck Instruments Inc., Richland, WA). Also, the semiquantitative chemical composition, the mineralogical study and the morphological aspect of the PG samples were analysed. The results obtained from both techniques show that 226Ra and 210Po are the main source of the radioactivity in both studied PG samples. However, PG samples from Tunisia present low natural radionuclide levels (30.7 Bq?kg–1 average value for 238U, 188 Bq?kg–1(226Ra), 163 Bq?kg–1(210Pb), 12.4 Bq?kg–1 (232Th)) compared to the level of natural radionuclides in PG samples from Huelva (102 Bq?kg–1 average value for 238U, 520 Bq?kg–1(226Ra), 881 Bq?kg-1(210Pb) and 8 Bq?kg-1 (232Th). Both PG fulfil European Commission Recommendation (ECR) for the maximum activity concentrations of naturally-occurring radionuclides for industrial by product used in building materials in the European Union.
Keywords: Phosphogypsum, Radionuclides Analysis, Phosphate Industry, Gamma Spectrometry, TENORM
Cite this paper: nullH. Tayibi, C. Gascó, N. Navarro, A. López-Delgado, M. Choura, F. Alguacil and F. López, "Radiochemical Characterization of Phosphogypsum for Engineering Use," Journal of Environmental Protection, Vol. 2 No. 2, 2011, pp. 168-174. doi: 10.4236/jep.2011.22019.
References

[1]   J. Yang, W. Liu, L. Zhang and B. Xiao, “Preparation of Load-Bearing Building Materials from Autoclaved Phos- phogypsum,” Construction and Building Materials, Vol. 23, 2009, pp. 687-693. doi:10.1016/j.conbuildmat.2008.02.011

[2]   A. B. Parreira, A. R. K. Jr. Kobayashi and O. B. Silvestre, “Influence of Portland Cement Type on Unconfined Compressive Strength and Linear Expansion of Cement- Stabilized Phosphogypsum,” Journal of Environmental Engineering, Vol. 129, 2003, pp. 956-960. doi:10.1061/(ASCE)0733-9372(2003)129:10(956)

[3]   H. Tayibi, M. Choura, F. A. López, F. J. Alguacil and A. López-Delgado, “Environmental Impact and Management of Phosphogypsum (Review),” Journal of Environmental Management, Vol. 90, 2009, pp. 2377-2386. doi:10.1016/j.jenvman.2009.03.007

[4]   J. P. Bolivar, R. Garcia-Tenorio and F. Vaca, “Radio- ecological Study of an Estuarine System Located in the South of Spain,” Water Research, Vol. 34, 2000, pp. 2941-2950. doi:10.1016/S0043-1354(99)00370-X

[5]   P. M. Rutherford, M. J. Dudas and R. A. Samek, “Environmental Impacts of Phosphogypsum,” Science of the Total Environment, Vol. 149, No. 1-2, 1994, pp. 1-38. doi:10.1016/0048-9697(94)90002-7

[6]   United States Environmental Protection Agency (USEPA), “National Emission Standards for Hazardous Air Pollutants,” Subpart R, 2002.

[7]   “Federal Register,” 40 CFR Part 61, Subpart 61, Vol. 64, No. 2, 3 February 1999, pp. 5573-5580.

[8]   USEPA, “Code of Federal Regulations,” Title 40, Vol. 7, Parts 61.202 and 61.204 (40CFR61.202 and 40CFR 61.204), 1998.

[9]   J. L. Mas, E. G. San Miguel, J. P. Bolívar, F. Vaca and J. P. Pérez-Moreno, “An Assay on the Effect of Preliminary Restoration Tasks Applied to a Large TENORM Wastes Disposal in the South-West of Spain,” Science of the Total Environment, Vol. 364, 2006, pp. 55-66. doi:10.1016/j.scitotenv.2005.11.006

[10]   R. Brina and A. G. Miller, “Direct Detection of Trace Levels of Uranium by LáSER-Induced Kinetic Phos- phorimetry,” Analytical Chemistry, Vol. 64, 1992, pp. 1413-1418. doi:10.1021/ac00037a020

[11]   “Uranium Radiation Properties,” WISE Uranium Project, 2006. http://www.wise-uranium.org/rup.html.

[12]   H. Tayibi, C. Gascó, N. Navarro, A. López-Delgado, M. Choura, F. J. Alguacil and F. A. López, 5 ème Edition, Journées Internationales des Géosciences de l’Environ- nement, Fès (Morocco), 2009.

[13]   W. W. Flynn, “The Determination of Low Level of Polonium-210 in Environmental Materials,” Analytica Chimica Acta, Vol. 43, 1968, pp. 221-227. doi:10.1016/S0003-2670(00)89210-7

[14]   H. Tayibi, C. Pérez, F. A., López, M. Choura and A. López-Delgado, “International Congress of Solid Waste Management & Sustainable Development,” Hammamet, Tunisia, 2008.

[15]   B. R. Milo? and V. T. Dragan, “Phosphogypsum Surface Characterisation Using Scanning Electron Microscopy,” Acta Periodica Technologica, Vol. 34, 2003, pp. 61-70.

[16]   W. C. Burnett, M. K. Schultz and D. H. Carter, “Radionuclide Flow during the Conversion of Phosphogypsum to Ammonium Sulphate,” Journal of Environmental Radioactivity, Vol. 32, No. 1-2, 1996, pp. 33-51. doi:10.1016/0265-931X(95)00078-O

[17]   E. M. El-Afifi, M. A. Hilal, M. F. Attallah and S. A. El- Reefy, “Characterization of Phosphogypse Wastes Associated Wit Phosphoric Acid and Fertilizers Production,” Journal of Environmental Radioactivity, Vol. 100, 2009, pp. 407-412. doi:10.1016/j.jenvrad.2009.01.005

[18]   “UNSCEAR: United Nations Scientific Committee on the Effect of Atomic, Radiation: Sources and Effects of Ionizing Radiation,” United Nations, New York, 1993.

[19]   C. Due?as, E. Liger, S. Ca?ete, M. Pérez and J. P. Bolívar, “Exhalation of 222Rn from Phosphogypsum Piles Located at the Southwest of Spain,” Journal of Environmental Radioactivity, Vol. 95, 2007, pp. 63-74. doi:10.1016/j.jenvrad.2007.01.012

[20]   J. P. Bolívar, J. E. Martín, R. García-Tenorio, J. P. Pérez- Moreno and J. L. Mas, “Behaviour and Fluxes of Natural Radionuclides in the Production Process of a Phosphoric Acid Plant,” Applied Radiation and Isotopes, Vol. 67, 2009, pp. 345-356. doi:10.1016/j.apradiso.2008.10.012

[21]   EC, “Radiological Protection Principals Concerning the Natural Radioactivity of Building Materials,” Radiation Protection Report RP-112, EC, European Commission, Luxembourg, 1999.

 
 
Top