The worldwide NORM production and a fully automated gamma-ray spectrometer for their characterization

Materials containing radionuclides of natural origin and being subject to regulation because of their radioactivity are known as Naturally Occurring Radioactive Material (NORM). By following International Atomic Energy Agency, we include in NORM those materials with an activity concentration, which is modified by human made processes. We present a brief review of the main categories of non-nuclear industries together with the levels of activity concentration in feed raw materials, products and waste, including mechanisms of radioisotope enrichments. The global management of NORM shows a high level of complexity, mainly due to different degrees of radioactivity enhancement and the huge amount of worldwide waste production. The future tendency of guidelines concerning environmental protection will require both a systematic monitoring based on the ever-increasing sampling and high performance of gamma-ray spectroscopy. On the ground of these requirements a new low-background fully automated high-resolution gamma-ray spectrometer MCA_Rad has been developed. The design of lead and cooper shielding allowed to reach a background reduction of two order of magnitude with respect to laboratory radioactivity. A severe lowering of manpower cost is obtained through a fully automation system, which enables up to 24 samples to be measured without any human attendance. Two coupled HPGe detectors increase the detection efficiency, performing accurate measurements on small sample volume (180 cm3) with a reduction of sample transport cost of material. Details of the instrument calibration method are presented. MCA_Rad system can measure in less than one hour a typical NORM sample enriched in U and Th with some hundreds of Bq kg−1, with an overall uncertainty less than 5 %. Quality control of this method has been tested. Measurements of three certified reference materials RGK-1, RGU-2 and RGTh-1 containing concentrations of potassium, uranium and thorium comparable to NORM have been performed. As a result, this test achieved an overall relative discrepancy of 5 % among central values within the reported uncertainty.

[1]  F. Carvalho.  210Pb and 210Po in sediments and suspended matter in the Tagus estuary, Portugal. Local enhancement of natural levels by wastes from phosphate ore processing industry , 1995 .

[2]  R. G. Menzel.  Uranium, radium, and thorium content in phosphate rocks and their possible radiation hazard , 1968 .

[3]  D. Alexiev,et al.  Evaluation of lead shielding for a gamma-spectroscopy system , 2008 .

[4]  Prosun Bhattacharya,et al.  Mercury flow via coal and coal utilization by-products: A global perspective , 2008 .

[5]  Serena Righi,et al.  Assessment of the radiological impacts of a zircon sand processing plant. , 2005, Journal of environmental radioactivity.

[6]  B. Heaton,et al.  TENORM in the oil, gas and mineral mining industry , 1995 .

[7]  C. Hazin,et al.  Radium and potassium-40 in solid wastes from the oil industry. , 2008, Applied radiation and isotopes : including data, instrumentation and methods for use in agriculture, industry and medicine.

[8]  Y. Pontikes,et al.  Environmental Aspects on the Use of Bayer's Process Bauxite Residue in the Production of Ceramics , 2006 .

[9]  M. Abo-Elmagd,et al.  Radiological hazards of TENORM in the wasted petroleum pipes. , 2010, Journal of environmental radioactivity.

[10]  Kuppusamy Thayalan,et al.  Radiation Detection and Measurements , 2014 .

[11]  A. Akıncı,et al.  Characterization of trace elements and radionuclides and their risk assessment in red mud , 2008 .

[12]  Tibor Kovács,et al.  Radiological aspects of the usability of red mud as building material additive. , 2008, Journal of hazardous materials.

[13]  M. A. Hilal,et al.  Characterization of phosphogypsum wastes associated with phosphoric acid and fertilizers production. , 2009, Journal of environmental radioactivity.

[14]  V. Metz,et al.  Geochemical evaluation of different groundwater-host rock systems for radioactive waste disposal. , 2003, Journal of Contaminant Hydrology.

[15]  C. Olsen,et al.  Direct analysis of 210Pb in sediment samples: Self-absorption corrections , 1983 .

[16]  K. Condie.  Chemical composition and evolution of the upper continental crust: Contrasting results from surface samples and shales , 1993 .

[17]  Z. Ahmad,et al.  Distribution of radium in oil and gas industry wastes from Malaysia. , 2004, Applied radiation and isotopes : including data, instrumentation and methods for use in agriculture, industry and medicine.

[18]  G. Papatheodorou,et al.  Natural radionuclides in bauxitic tailings (red-mud) in the Gulf of Corinth, Greece , 2005 .

[19]  M. Flues,et al.  Radioactivity of coal and ashes from Figueira coal power plant in Brazil , 2006 .

[20]  C.W.M. Timmermans,et al.  Environmental and occupational impacts of natural radioactivity from some non-nuclear industries in the Netherlands , 1996 .

[21]  J. Godoy,et al.  226Ra and 228Ra in scale and sludge samples and their correlation with the chemical composition. , 2003, Journal of environmental radioactivity.

[22]  William C. Burnett,et al.  Radiochemistry of Florida phosphogypsum , 1996 .

[23]  I. Mcpharlin,et al.  An investigation of radionuclide uptake into food crops grown in soils treated with bauxite mining residues , 1995 .

[24]  Serena Righi,et al.  Radioactivity in raw materials and end products in the Italian ceramics industry , 2000 .

[25]  Ş. Turhan,et al.  Radiometric analysis of raw materials and end products in the Turkish ceramics industry , 2011 .

[26]  杨辉,et al.  Production of titanium dioxide optical catalyst sol , 2005 .

[27]  P. Dryák,et al.  Table for true summation effect in gamma-ray spectrometry , 2009 .

[28]  F. S. Al-Saleh,et al.  Measurements of radiation level in petroleum products and wastes in Riyadh City Refinery. , 2008, Journal of environmental radioactivity.

[29]  L. A. Currie,et al.  LIMITS FOR QUALITATIVE DETECTION AND QUANTITATIVE DETERMINATION. APPLICATION TO RADIOCHEMISTRY. , 1968 .

[30]  P. Felice,et al.  Fast procedures for coincidence-summing correction in γ-ray spectrometry , 2000 .

[31]  Suresh K. Bhargava,et al.  The surface chemistry of Bayer process solids: a review , 1999 .

[32]  M. García-León,et al.  On Self-attenuation Corrections in Gamma-ray Spectrometry , 1997 .

[33]  岩崎 民子.  SOURCES AND EFFECTS OF IONIZING RADIATION : United Nations Scientific Committee on the Effects of Atomic Radiation UNSCEAR 2000 Report to the General Assembly, with Scientific Annexes , 2002 .

[34]  H. Suman,et al.  NORM waste management in the oil and gas industry: The Syrian experience , 2003 .

[35]  J. Godoy,et al.  Environmental impact studies of barium and radium discharges by produced waters from the "Bacia de Campos" oil-field offshore platforms, Brazil. , 2002, Journal of environmental radioactivity.

[36]  Fazio,et al.  Fast procedures for coincidence-summing correction in gamma-ray spectrometry , 2000, Applied radiation and isotopes : including data, instrumentation and methods for use in agriculture, industry and medicine.

[37]  A. Paschoa.  Potential environmental and regulatory implications of naturally occurring radioactive materials (NORM). , 1998, Applied radiation and isotopes : including data, instrumentation and methods for use in agriculture, industry and medicine.

[38]  P. Landais.  Organic geochemistry of sedimentary uranium ore deposits , 1996 .

[39]  John L. Sznopek,et al.  Historical Statistics for Mineral Commodities in the United States , 2001 .

[40]  M. Benmansour,et al.  Natural radioactivity in phosphates, phosphogypsum and natural waters in Morocco. , 2001, Journal of environmental radioactivity.

[41]  R. Zielinski,et al.  Use of radium isotopes to determine the age and origin of radioactive barite at oil-field production sites. , 2001, Environmental pollution.

[42]  R. Guimond,et al.  Radioactivity released from phosphate-containing fertilizers and from gypsum , 1989 .

[43]  J Beretka,et al.  Natural radioactivity of Australian building materials, industrial wastes and by-products. , 1985, Health physics.

[44]  W. Pinnock.  Measurements of radioactivity in Jamaican building materials and gamma dose equivalents in a prototype red mud house. , 1991, Health physics.

[45]  F. Corte,et al.  Calculation of the absolute peak efficiency of gamma-ray detectors for different counting geometries , 1981 .

[46]  S. Black,et al.  Naturally occurring radioactive material (NORM) from a former phosphoric acid processing plant. , 2006, Journal of environmental radioactivity.

[47]  D. I. Fávaro,et al.  Natural radioactivity in phosphate rock, phosphogypsum and phosphate fertilizers in Brazil , 2005 .

[48]  M. H. T. Taddei,et al.  The natural radioactivity of Brazilian phosphogypsum , 2001 .

[49]  S. Shawky,et al.  Characteristics of NORM in the oil industry from eastern and western deserts of Egypt. , 2001, Applied radiation and isotopes : including data, instrumentation and methods for use in agriculture, industry and medicine.

[50]  A. Young,et al.  The natural radioactivity of phosphate ore and associated waste products discharged into the eastern Irish Sea from a phosphoric acid production plant , 1995 .

[51]  B. Mazzilli,et al.  Partitioning of radionuclides and trace elements in phosphogypsum and its source materials based on sequential extraction methods. , 2006, Journal of environmental radioactivity.

[52]  C. Hazin,et al.  Radioactivity concentration in liquid and solid phases of scale and sludge generated in the petroleum industry. , 2005, Journal of environmental radioactivity.

[53]  G. Knoll.  Radiation detection and measurement , 1979 .

[54]  H. Beck.  Radiation exposures due to fossil fuel combustion , 1989 .

[55]  J. Kovács,et al.  Dependence of radon emanation of red mud bauxite processing wastes on heat treatment. , 2009, Journal of hazardous materials.

[56]  J. Tadmor.  Radioactivity from coal-fired power plants: A review , 1986 .

[57]  A. Fazio,et al.  Close-geometry efficiency calibration of p-type HPGe detectors with a Cs-134 point source. , 2006, Applied Radiation and Isotopes.

[58]  Aurora López-Delgado,et al.  Environmental impact and management of phosphogypsum. , 2009, Journal of environmental management.

[59]  Jelle Mertens,et al.  The red mud accident in ajka (hungary): plant toxicity and trace metal bioavailability in red mud contaminated soil. , 2011, Environmental science & technology.

[60]  W. Bakr.  Assessment of the radiological impact of oil refining industry. , 2010, Journal of environmental radioactivity.

[61]  B. Mazzilli,et al.  Distribution of natural radionuclides in the production and use of phosphate fertilizers in Brazil. , 2006, Journal of environmental radioactivity.

[62]  Barbara Paci Mazzilli,et al.  Radiochemical characterization of Brazilian phosphogypsum , 2000 .

[63]  S. Rizzo,et al.  Coincidence-summing correction equations in gamma-ray spectrometry with p-type HPGedetectors , 2011 .

[64]  Marc Schattenmann,et al.  IAEA – International Atomic Energy Agency , 2000, A Concise Encyclopedia of the United Nations.

[65]  A. Cesana,et al.  An empirical method for peak-to-total ratio computation of a gamma-ray detector , 1989 .

[66]  M. J. Vargas,et al.  Radioactive content of charcoal. , 2009 .

[67]  S. Nakashima.  Complexation and reduction of uranium by lignite , 1992 .

[68]  John A. S. Adams,et al.  Thorium, uranium and zirconium concentrations in bauxite , 1960 .