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Tibor Kovács - One of the best experts on this subject based on the ideXlab platform.
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Enrichment of Naturally Occurring Radionuclides and trace elements in Yatagan and Yenikoy coal-fired thermal power plants, Turkey.
Journal of environmental radioactivity, 2017Co-Authors: Banu Özden, Erkan Güler, Taavi Vaasma, Mária Horváth, Madis Kiisk, Tibor KovácsAbstract:Coal, residues and waste produced by the combustion of the coal contain Naturally Occurring Radionuclides such as 238U, 226Ra, 210Pb, 232Th and 40K and trace elements such as Cd, Cr, Pb, Ni and Zn. In this work, coal and its combustion residues collected from Yatagan and Yenikoy coal fired thermal power plants (CPPs) in Turkey were studied to determine the concentrations of natural Radionuclides and trace elements, and their enrichments factors to better understand the radionuclide concentration processes within the combustion system. In addition, the utilization of coal fly ash as a secondary raw material in building industry was also studied in terms of radiological aspects. Fly ash samples were taken at different stages along the emission control system of the thermal power plants. Activity concentrations of Naturally Occurring Radionuclides were determined with Canberra Broad Energy Germanium (BEGe) detector BE3830-P and ORTEC Soloist PIPS type semiconductor detector. The particle size distribution and trace elements contents were determined in various ash fractions by the laser scattering particle size distribution analyzer and inductively coupled plasma (ICP-OES). From the obtained data, natural Radionuclides tend to condense on fly ash with and the activity concentrations increase as the temperature drop in CPPs. Measured 210Pb and 210Po concentration varied between 186 ± 20-1153 ± 44 Bq kg-1, and 56 ± 5-1174 ± 45 Bq kg-1, respectively. The highest 210Pb and 210Po activity concentrations were determined in fly ash taken from the temporary storage point as 1153 ± 44 Bq kg-1 and 1174 ± 45 Bq kg-1, respectively. There were significant differences in the activity concentrations of some natural radionuclide and trace elements (Pb and Zn) contents in ash fractions among the sampling point inside both of the plants (ANOVA, p
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enrichment of Naturally Occurring Radionuclides and trace elements in yatagan and yenikoy coal fired thermal power plants turkey
Journal of Environmental Radioactivity, 2017Co-Authors: Banu Özden, Erkan Güler, Taavi Vaasma, Mária Horváth, Madis Kiisk, Tibor KovácsAbstract:Coal, residues and waste produced by the combustion of the coal contain Naturally Occurring Radionuclides such as 238U, 226Ra, 210Pb, 232Th and 40K and trace elements such as Cd, Cr, Pb, Ni and Zn. In this work, coal and its combustion residues collected from Yatagan and Yenikoy coal fired thermal power plants (CPPs) in Turkey were studied to determine the concentrations of natural Radionuclides and trace elements, and their enrichments factors to better understand the radionuclide concentration processes within the combustion system. In addition, the utilization of coal fly ash as a secondary raw material in building industry was also studied in terms of radiological aspects. Fly ash samples were taken at different stages along the emission control system of the thermal power plants. Activity concentrations of Naturally Occurring Radionuclides were determined with Canberra Broad Energy Germanium (BEGe) detector BE3830-P and ORTEC Soloist PIPS type semiconductor detector. The particle size distribution and trace elements contents were determined in various ash fractions by the laser scattering particle size distribution analyzer and inductively coupled plasma (ICP-OES). From the obtained data, natural Radionuclides tend to condense on fly ash with and the activity concentrations increase as the temperature drop in CPPs. Measured 210Pb and 210Po concentration varied between 186 ± 20-1153 ± 44 Bq kg-1, and 56 ± 5-1174 ± 45 Bq kg-1, respectively. The highest 210Pb and 210Po activity concentrations were determined in fly ash taken from the temporary storage point as 1153 ± 44 Bq kg-1 and 1174 ± 45 Bq kg-1, respectively. There were significant differences in the activity concentrations of some natural radionuclide and trace elements (Pb and Zn) contents in ash fractions among the sampling point inside both of the plants (ANOVA, p < 0.001). Coal and ash sample analysis showed an increase activity concentration and enrichment factors towards the electrostatic precipitators for both of the power plants. The enrichment factors for Zn follow a similar trend as Pb, increasing in value towards the end of the emission control system. The calculated activity indexes were above 1.0 value for both of the power plants, assuming the utilization of fly ash at 100%. It can be concluded that the reuse of fly ash as a secondary raw material may not be hazardous depending on the percentage of utilization of ash.
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From raw materials to NORM by-products
Naturally Occurring Radioactive Materials in Construction, 2017Co-Authors: Tibor Kovács, Wouter Schroeyers, Gergo Bator, João A. Labrincha, Francisca Puertas, Miklos Hegedus, D. Nicolaides, M.a. Sanjuán, Krivenko Pavel, I.n. GrubešaAbstract:Abstract Naturally Occurring Radionuclides are present in the Earth crust; however, their distribution is not homogeneous. When primary or secondary raw materials containing relatively low concentrations of Naturally Occurring Radionuclides are introduced in an industrial process then the Radionuclides can become more concentrated in the produced (by-)products. For example, during the production of purified metals, throughout the purification process, also other elements, such as Naturally Occurring Radionuclides, become concentrated in the by-products. In order to assure radiation protection of the population, it is important to map the potential exposure for workers and the general public. There is an extensive literature available regarding the presence of Naturally Occurring Radionuclides in various by-products; however, it can be hard to review and even to interpret for the regulators and members of the industry in order to assure the safe use of by-products for example in construction. To solve this problem data mining and text processing have been applied to the ever-increasing numbers of publications (More than 39,000 filtered publications have been processed up to the Jan. 6, 2017), and the NORM4Building database has been compiled based on the analysis of the collected data. Based on this database using text analysis methods the most NORM prone raw materials and industries have been identified. This chapter gives a concise overview on the parameters to be considered during the selection of NORM by-products as feedstock for the construction industry, specifically for the production of cement, concrete, and ceramics. In the frame of this chapter the technical and radiological properties of the most representative industrial processes (such as coal mining and combustion; iron and steel production; the alumina, the zirconia, and the phosphate industry; etc.) and their by-products are discussed, especially considering the needs of the construction industry and the new European Basic Safety Standards.
Andrew L. Herczeg - One of the best experts on this subject based on the ideXlab platform.
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Naturally Occurring Radionuclides in acid saline groundwaters around lake tyrrell victoria australia
Chemical Geology, 1992Co-Authors: B.l. Dickson, Andrew L. HerczegAbstract:Abstract Many natural Radionuclides have been measured in regional groundwater, acid spring waters and brines in the vicinity of Lake Tyrrell, Victoria. The concentration of nuclides within the U and Th decay series range over several orders of magnitude. The acid groundwaters display very high Ac, Ra, 222Rn, 210Pb and 210Po activities in the springs on the western margin of the lake compared to those generally recorded in less saline and neutral groundwaters. This is an area of the lake margin where 226Ra and 228Ra have accumulated in shallow sediments. Measured and estimated distribution coefficients for 226Ra range from 10 to 800, which combined with flow rates places the source of the 226Ra within 5 km of the radioactive spring zone. 227Ac showed the strongest control by pH of all the measured Radionuclides and was similar to Al in this behaviour. 210Pb and 210Po appear to be quite mobile at high salinity when pH was
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Naturally-Occurring Radionuclides in acid—Saline groundwaters around Lake Tyrrell, Victoria, Australia
Chemical Geology, 1992Co-Authors: B.l. Dickson, Andrew L. HerczegAbstract:Abstract Many natural Radionuclides have been measured in regional groundwater, acid spring waters and brines in the vicinity of Lake Tyrrell, Victoria. The concentration of nuclides within the U and Th decay series range over several orders of magnitude. The acid groundwaters display very high Ac, Ra, 222Rn, 210Pb and 210Po activities in the springs on the western margin of the lake compared to those generally recorded in less saline and neutral groundwaters. This is an area of the lake margin where 226Ra and 228Ra have accumulated in shallow sediments. Measured and estimated distribution coefficients for 226Ra range from 10 to 800, which combined with flow rates places the source of the 226Ra within 5 km of the radioactive spring zone. 227Ac showed the strongest control by pH of all the measured Radionuclides and was similar to Al in this behaviour. 210Pb and 210Po appear to be quite mobile at high salinity when pH was
Banu Özden - One of the best experts on this subject based on the ideXlab platform.
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Enrichment of Naturally Occurring Radionuclides and trace elements in Yatagan and Yenikoy coal-fired thermal power plants, Turkey.
Journal of environmental radioactivity, 2017Co-Authors: Banu Özden, Erkan Güler, Taavi Vaasma, Mária Horváth, Madis Kiisk, Tibor KovácsAbstract:Coal, residues and waste produced by the combustion of the coal contain Naturally Occurring Radionuclides such as 238U, 226Ra, 210Pb, 232Th and 40K and trace elements such as Cd, Cr, Pb, Ni and Zn. In this work, coal and its combustion residues collected from Yatagan and Yenikoy coal fired thermal power plants (CPPs) in Turkey were studied to determine the concentrations of natural Radionuclides and trace elements, and their enrichments factors to better understand the radionuclide concentration processes within the combustion system. In addition, the utilization of coal fly ash as a secondary raw material in building industry was also studied in terms of radiological aspects. Fly ash samples were taken at different stages along the emission control system of the thermal power plants. Activity concentrations of Naturally Occurring Radionuclides were determined with Canberra Broad Energy Germanium (BEGe) detector BE3830-P and ORTEC Soloist PIPS type semiconductor detector. The particle size distribution and trace elements contents were determined in various ash fractions by the laser scattering particle size distribution analyzer and inductively coupled plasma (ICP-OES). From the obtained data, natural Radionuclides tend to condense on fly ash with and the activity concentrations increase as the temperature drop in CPPs. Measured 210Pb and 210Po concentration varied between 186 ± 20-1153 ± 44 Bq kg-1, and 56 ± 5-1174 ± 45 Bq kg-1, respectively. The highest 210Pb and 210Po activity concentrations were determined in fly ash taken from the temporary storage point as 1153 ± 44 Bq kg-1 and 1174 ± 45 Bq kg-1, respectively. There were significant differences in the activity concentrations of some natural radionuclide and trace elements (Pb and Zn) contents in ash fractions among the sampling point inside both of the plants (ANOVA, p
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enrichment of Naturally Occurring Radionuclides and trace elements in yatagan and yenikoy coal fired thermal power plants turkey
Journal of Environmental Radioactivity, 2017Co-Authors: Banu Özden, Erkan Güler, Taavi Vaasma, Mária Horváth, Madis Kiisk, Tibor KovácsAbstract:Coal, residues and waste produced by the combustion of the coal contain Naturally Occurring Radionuclides such as 238U, 226Ra, 210Pb, 232Th and 40K and trace elements such as Cd, Cr, Pb, Ni and Zn. In this work, coal and its combustion residues collected from Yatagan and Yenikoy coal fired thermal power plants (CPPs) in Turkey were studied to determine the concentrations of natural Radionuclides and trace elements, and their enrichments factors to better understand the radionuclide concentration processes within the combustion system. In addition, the utilization of coal fly ash as a secondary raw material in building industry was also studied in terms of radiological aspects. Fly ash samples were taken at different stages along the emission control system of the thermal power plants. Activity concentrations of Naturally Occurring Radionuclides were determined with Canberra Broad Energy Germanium (BEGe) detector BE3830-P and ORTEC Soloist PIPS type semiconductor detector. The particle size distribution and trace elements contents were determined in various ash fractions by the laser scattering particle size distribution analyzer and inductively coupled plasma (ICP-OES). From the obtained data, natural Radionuclides tend to condense on fly ash with and the activity concentrations increase as the temperature drop in CPPs. Measured 210Pb and 210Po concentration varied between 186 ± 20-1153 ± 44 Bq kg-1, and 56 ± 5-1174 ± 45 Bq kg-1, respectively. The highest 210Pb and 210Po activity concentrations were determined in fly ash taken from the temporary storage point as 1153 ± 44 Bq kg-1 and 1174 ± 45 Bq kg-1, respectively. There were significant differences in the activity concentrations of some natural radionuclide and trace elements (Pb and Zn) contents in ash fractions among the sampling point inside both of the plants (ANOVA, p < 0.001). Coal and ash sample analysis showed an increase activity concentration and enrichment factors towards the electrostatic precipitators for both of the power plants. The enrichment factors for Zn follow a similar trend as Pb, increasing in value towards the end of the emission control system. The calculated activity indexes were above 1.0 value for both of the power plants, assuming the utilization of fly ash at 100%. It can be concluded that the reuse of fly ash as a secondary raw material may not be hazardous depending on the percentage of utilization of ash.
A Baeza - One of the best experts on this subject based on the ideXlab platform.
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Transfer of Naturally Occurring Radionuclides to wheat under laboratory controlled conditions
Journal of Radioanalytical and Nuclear Chemistry, 2019Co-Authors: J. G. Muñoz-muñoz, A Baeza, Francisco Javier Guillén, Alejando Salas, Francisco Manuel Gómez-poloAbstract:Knowledge of soil–plant transfer of Naturally Occurring Radionuclides can be essential to assure an adequate radiological protection. Available data are mainly for anthropogenic Radionuclides and biased for temperate climates. Wheat plantlets were grown using soil collected in Mediterranean regions and transfer factors, TF, for 234,238U, 226Ra, 210Po and stable elements (K, Na, Ca and Mg) were determined. U, Ra and Po were mainly located in roots. Calcium presented the highest TF values, whereas for Radionuclides were much lower. Uranium TFs were correlated with total and exchangeable potassium concentration in soil. Calcium and radium TFs were correlated with total calcium concentration in soil.
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Speciation of Naturally Occurring Radionuclides in Mediterranean soils: bioavailabilty assessment.
Environmental science and pollution research international, 2017Co-Authors: Javier Guillén, A Baeza, Ana Muñoz-serrano, A SalasAbstract:Knowledge of soil-to-plant transfer processes is a key element that can have a significant health impact. Much effort has been taken to characterize the speciation of anthropogenic Radionuclides released into the environment. However, the information about Naturally Occurring Radionuclides is scarce. This work evaluate the potential risks of transference, that is, the bioavailability of the 234,238U, 226Ra, 228,230,232Th, and 210Po in three different soils collected in Mediterranean ecosystems. Chemical speciation of these Radionuclides was carried out according to two different methods, Pavlotskaya and a modification of Tessier’s protocol. Most of these Radionuclides were associated to fractions strongly bound to soil particles and not able to be transferred. Increasing concentrations of U and Th extracted with increasing volume of NH4OAc 1 M were observed, until it reached saturation. Readily bioavailable fraction in both methods (either exchangeable or water soluble + exchangeable) decreased in the following order: 226Ra > 234,238 U > 228,230,232Th > 210Po. It was found that < 3% of the natural radionuclide concentration in soil are readily bioavailable for plant uptake in this region of Spain, and the resulting human health risk is negligible from natural radionuclide ingestion.
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removal Naturally Occurring Radionuclides from drinking water using a filter specifically designed for drinking water treatment plants
Chemosphere, 2017Co-Authors: A Baeza, A Salas, J Guillen, A Munozserrano, M A Ontalbasalamanca, M C JimenezramosAbstract:The occurrence of Naturally Occurring Radionuclides in drinking water can pose health hazards in some populations, especially taking into account that routine procedures in Drinking Water Treatment Plants (DWTPs) are normally unable to remove them efficiently from drinking water. In fact, these procedures are practically transparent to them, and in particular to radium. In this paper, the characterization and capabilities of a patented filter designed to remove radium from drinking water with high efficiency is described. This filter is based on a sandwich structure of silica and green sand, with a natural high content manganese oxide. Both sands are authorized by Spanish authorities to be used in Drinking Water Treatment Plants. The Mn distribution in the green sand was found to be homogenous, thus providing a great number of adsorption sites for radium. Kinetic studies showed that the 226Ra adsorption on green sand was influenced by the content of major cations solved in the treated water, but the saturation level, about 96–99%, was not affected by it. The physico-chemical parameters of the treated water were unaltered by the filter. The efficiency of the filter for the removal of 226Ra remained unchanged with large water volumes passed through it, proving its potential use in DWTP. This filter was also able to remove initially the uranium content due to the presence of Fe2O3 particles in it, although it is saturated faster than radium.
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Accuracy associated with the activity determination by in situ gamma spectrometry of Naturally Occurring Radionuclides in soils
Journal of Environmental Radioactivity, 2016Co-Authors: A Baeza, J.a. Corbacho, Javier GuillénAbstract:In situ gamma spectrometry (ISGS) is a technique mainly focused on the determination of man-made Radionuclides deposited on soils. It is widely used for the radioactive characterization of soils in which there has been an incorporation of such Radionuclides, especially 137Cs. Its use for the activity determination of Naturally Occurring Radionuclides in soils has been more limited, and the accuracy associated with those measurements has yet to be treated extensively. There are numerous factors affecting the accuracy of the activity determination of Naturally Occurring Radionuclides, such as the assumed soil geometry, the soil's geological and mineral composition, its moisture content, etc. The present work studies the accuracy associated with the ISGS determination of the activity concentrations of natural Radionuclides in soils using a portable HPGe detector. For 40K and 232Th activity determinations, the uncertainties associated with ISGS are generally of the order of 15%. However, 226Ra activity determined from its daughters 214Pb and 214Bi can be significantly overestimated when there is a major presence of 222Rn in the air around the detector. Finally, absorbed dose rate in air values were calculated from the Naturally Occurring radionuclide concentration in soils. The results showed good correspondence between the values obtained from ISGS and those obtained from laboratory determinations with the same soils.
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Environmental impact of a granite processing factory as source of Naturally Occurring Radionuclides
Applied Geochemistry, 2014Co-Authors: Javier Guillén, A Baeza, A Salas, J. J. Tejado, J. G. Muñoz-muñozAbstract:Abstract The extraction and processing of ornamental stone, and granite in particular, generates a huge amount of wastes, which are usually disposed into slag heaps and subjected to weathering. Granite can present high content of Naturally Occurring Radionuclides (40K, 226,228Ra, 234,238U, 210Po, and 228,230,232Th). A small-scale granite processing company was selected, and the generated wastes, mainly scraps and slurries, presented almost the same activity levels, since only physical processes (cutting) were used. Uranium and 40K content in the water used in the factory as coolant were enhanced regarding its original value, as a consequence of its contact with the slurries. Other physico-chemical parameters of the water (pH, conductivity, Cl, K, Na, Mg) also increased. The environmental behavior of Naturally Occurring Radionuclides contained in solid wastes, scraps and slurries, were assessed by means of a sequential extraction procedure. Uranium in scraps and slurries was mainly associated with diluted-acid (HCl 1 M), concentrated-acid (HCl 6 M), and residual fractions; while 40K was almost exclusively associated with the residual fraction. The readily bioavailable fraction (water soluble + exchangeable) in scrap and slurry were lower than 20%, and decreased in the following order: 226,228Ra > 234,238U > 40K » 210Po ≈ 228,230,232Th.
Javier Guillén - One of the best experts on this subject based on the ideXlab platform.
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Speciation of Naturally Occurring Radionuclides in Mediterranean soils: bioavailabilty assessment.
Environmental science and pollution research international, 2017Co-Authors: Javier Guillén, A Baeza, Ana Muñoz-serrano, A SalasAbstract:Knowledge of soil-to-plant transfer processes is a key element that can have a significant health impact. Much effort has been taken to characterize the speciation of anthropogenic Radionuclides released into the environment. However, the information about Naturally Occurring Radionuclides is scarce. This work evaluate the potential risks of transference, that is, the bioavailability of the 234,238U, 226Ra, 228,230,232Th, and 210Po in three different soils collected in Mediterranean ecosystems. Chemical speciation of these Radionuclides was carried out according to two different methods, Pavlotskaya and a modification of Tessier’s protocol. Most of these Radionuclides were associated to fractions strongly bound to soil particles and not able to be transferred. Increasing concentrations of U and Th extracted with increasing volume of NH4OAc 1 M were observed, until it reached saturation. Readily bioavailable fraction in both methods (either exchangeable or water soluble + exchangeable) decreased in the following order: 226Ra > 234,238 U > 228,230,232Th > 210Po. It was found that < 3% of the natural radionuclide concentration in soil are readily bioavailable for plant uptake in this region of Spain, and the resulting human health risk is negligible from natural radionuclide ingestion.
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Accuracy associated with the activity determination by in situ gamma spectrometry of Naturally Occurring Radionuclides in soils
Journal of Environmental Radioactivity, 2016Co-Authors: A Baeza, J.a. Corbacho, Javier GuillénAbstract:In situ gamma spectrometry (ISGS) is a technique mainly focused on the determination of man-made Radionuclides deposited on soils. It is widely used for the radioactive characterization of soils in which there has been an incorporation of such Radionuclides, especially 137Cs. Its use for the activity determination of Naturally Occurring Radionuclides in soils has been more limited, and the accuracy associated with those measurements has yet to be treated extensively. There are numerous factors affecting the accuracy of the activity determination of Naturally Occurring Radionuclides, such as the assumed soil geometry, the soil's geological and mineral composition, its moisture content, etc. The present work studies the accuracy associated with the ISGS determination of the activity concentrations of natural Radionuclides in soils using a portable HPGe detector. For 40K and 232Th activity determinations, the uncertainties associated with ISGS are generally of the order of 15%. However, 226Ra activity determined from its daughters 214Pb and 214Bi can be significantly overestimated when there is a major presence of 222Rn in the air around the detector. Finally, absorbed dose rate in air values were calculated from the Naturally Occurring radionuclide concentration in soils. The results showed good correspondence between the values obtained from ISGS and those obtained from laboratory determinations with the same soils.
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Environmental impact of a granite processing factory as source of Naturally Occurring Radionuclides
Applied Geochemistry, 2014Co-Authors: Javier Guillén, A Baeza, A Salas, J. J. Tejado, J. G. Muñoz-muñozAbstract:Abstract The extraction and processing of ornamental stone, and granite in particular, generates a huge amount of wastes, which are usually disposed into slag heaps and subjected to weathering. Granite can present high content of Naturally Occurring Radionuclides (40K, 226,228Ra, 234,238U, 210Po, and 228,230,232Th). A small-scale granite processing company was selected, and the generated wastes, mainly scraps and slurries, presented almost the same activity levels, since only physical processes (cutting) were used. Uranium and 40K content in the water used in the factory as coolant were enhanced regarding its original value, as a consequence of its contact with the slurries. Other physico-chemical parameters of the water (pH, conductivity, Cl, K, Na, Mg) also increased. The environmental behavior of Naturally Occurring Radionuclides contained in solid wastes, scraps and slurries, were assessed by means of a sequential extraction procedure. Uranium in scraps and slurries was mainly associated with diluted-acid (HCl 1 M), concentrated-acid (HCl 6 M), and residual fractions; while 40K was almost exclusively associated with the residual fraction. The readily bioavailable fraction (water soluble + exchangeable) in scrap and slurry were lower than 20%, and decreased in the following order: 226,228Ra > 234,238U > 40K » 210Po ≈ 228,230,232Th.
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Association of Naturally Occurring Radionuclides in sludges from Drinking Water Treatment Plants previously optimized for their removal.
Chemosphere, 2013Co-Authors: A Baeza, A Salas, Javier Guillén, A. Muñoz-serranoAbstract:Abstract The raw water used in Drinking Water Treatment Plants (DWTPs) can present high values of Naturally Occurring Radionuclides. In order to reduce this content, the routine working conditions of DWTPs were successfully modified. This meant that those Radionuclides were accumulated in the sludges generated, whose radioactive content was frequently above the exemption levels. It therefore becomes necessary to assess the association of Naturally Occurring Radionuclides in the sludges for their potential use as agricultural fertilizers. Two approaches were studied: (a) the effect of different sequential extraction methods applied to a selected sludge; and (b) the effect of the different contents of inorganic complexes dissolved in the input water on the composition of the sludges generated by two DWTPs with different origins of their input water. Uranium and radium were mainly associated with the carbonated and reducible fractions, while 210Po and 228Th were associated with the residual fraction. There were differences between the two speciation methods, but the order of bioavailable Radionuclides was roughly the same: 226Ra ≈ 234,238U > 228Th > 210Po. The major inorganic complexes content, mainly carbonate, in the raw water affected the radionuclide association. The greater the carbonate content in the raw water, the greater was the association of uranium and radium with the carbonated and easily reducible fractions.
