Measurements of radionuclides in coal samples from two provinces of Pakistan and computation of External γ ray dose rate in coal mines (original) (raw)
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Use of the coal in order to generate electricity increases the exposure of people to radiation. In this paper, the activity concentrations of nuclides 226 Ra, 232 Th and 40 K in samples of coal and bottom ash from the Yatagan Coal–Fired thermal power plant determined using gamma ray spectrometer with a NaI(Tl) scintillation detector. The mean activity concentrations of 226 Ra, 232 Th, and 40 K in the coal were found to be 37.2±2.8 Bqkg -1 , 51.8±3.4 Bqkg -1 and 166.7±11.1 Bqkg -1 , respectively. Whereas in the bottom ashes, the concentrations of the corresponding radionuclides were found to be 62.2±5.6 Bqkg -1 , 87.4±5.9 Bqkg -1 and 221.0 ±12.5 Bqkg -1 , respectively. The findings show that bottom ashes show higher activity concentrations of related radionuclide to coal samples. The absorbed gamma dose rate in outdoor air DR OUT and annual effective dose rate (AED) from coal were calculated to define radiological risk. The average findings of annual effective doses were detected as ...
Analysis of Natural Radioactivity in Coal and Ashes from a Coal Fired Power Plant
Coal is widely used mineral due to its accessibility and abundance in nature. Coal contains naturally occurring radionuclides or Natural Occurring Radioactive Materials (NORM) from Uranium and Thorium series including their decayed daughters namely Uranium-238 (238 U), Radium-226 (226 Ra) and Thorium-232 (232 Th) along with Potassium-40 (40 K). These radionuclides which are a natural phenomenon are released to the environment and concentrated in the ashes resulting from the combustion process. This paper presents an evaluation of the radioactivity content found in the feed coal (FC), bottom ash (BA) and fly ash (FA) sampled from a typical coal fired power plant (CFPP). The samples were measured for activity concentration of several radionuclides namely 238 U, 226 Ra, 232 Th and 40 K by using Instrumental Neutron Activation Analysis (INAA). The radiological hazard based on Radium Equilibrium (Raeq) and External Hazard Index (Hex) was assessed. In this study the activity concentration of all radionuclides in FA was enriched much higher compared to BA and FC. This work found that the degree of enrichment determined by the Enrichment Factor (EF) is differed for bottom and fly ash. The results indicated that each sample have different radiological characteristics. For Raeq and Hex the values calculated for the samples were acceptable and within the limit for construction material. Generally the results proved that the values obtained were much lower and complied with the Malaysia regulatory limit and global values.
Journal of Nuclear and Particle Physics, 2013
The activity concentrations of naturally occurring radionuclides Ra-226, Th-232 and K-40, were measured by using a gamma ray spectrometry for coal, soil and water samp les collected fro m the Barapukuria coal mine in Dinajpur district of Bangladesh. The average activity concentrations of Ra-226, Th-232 and K-40 in coal samples were found to be 6.21±3.68, 10.69±7.5 and 185.76±138.86 Bq kg -1 , respectively; and those for active soil samples were found to be 23.54±2.6, 52.10±4.73 and 603.17±66.40 Bqkg -1 , respectively; and for passive soil samples were 36.75±3.38, 76.79±5.53 and 607.18±83.50 Bq kg -1 , respectively. The results for both the soil samples obtained for the corresponding nuclides are slightly higher than the wo rld wide average values of 35, 30 and 400 Bq kg -1 respectively except that of Ra-226 for active soil samples. The activity contents of the water samp les did not show any evidence of enhancement due to the min ing activit ies. The average absorbed dose rate (D) a...
Environment International, 1996
Investigations carried out in the vicinity of four coal-tired power plants showed that the average annual emission of natural radionuclides for each MWe of produced electric power is an average of 0.200 MBq for each component of 238U chain, and of 0.130 MBq for each component of 232Th chain, respectively, and of 1.027 MBq for 4%. The average annual absorbed dose of about 1 mGy was found on five locations studied. The results of specific activity measurements on the samples taken from several locations studied showed that there is a concentration of natural radionuclides in ash and slag of up to about five times. The absorbed dose levels found on depots of ash and slag were close to the values recommended by the International Commission on Radiological Protection.
Journal of Radiation and Nuclear Applications, 2018
Soil samples were collected from four tehsils of district Chakwal, Pakistan with an aim to measure naturally occurring radio-nuclides in this region. Radioactivities of 226 Ra, 232 Th and 40 K are measured using high purity germanium (HPGe) based gamma ray spectrometry system. The measured mean specific activity concentrations of 226 Ra, 232 Th and 40 K in the soil samples was 34.27 ± 1.28, 51.59 ± 2.73 Bqkg-1 and 606.42 ± 21.23 Bqkg-1. From the measured activity concentrations of soil samples, radium equivalent activity, external and internal hazard indices, terrestrial absorbed dose, gamma representative Index, annual effective dose, annual gonadal dose equivalent, and estimated life time cancer risk were calculated. Mean radium equivalent activity (Raeq), outdoor radiation hazard index (Hex), indoor radiation hazard index (Hin), absorbed dose rate (D) and gamma representative Index (Iγ) for soil were found to be 155.02 ± 6.66 Bqkg-1 0.42 ± 0.2, 0.51 ± 0.2, 73.35 ± 2.69 nGyh-1 and 1.15 ± 0.01 respectively. The calculated annual effective dose, annual gonadal dose, and estimated life time cancer risk for soil samples were 0.13 ± 0.01 mSvy-1 ,512.78 ± 18.50 mSvy-1 , and 0.47 x 10-3 respectively. Frequency distribution and activity concentration of measured radionuclides for all sampling sites are presented. The geo statistical mapping was created to indicate the activity distribution in the studied area. On the basis of measured activity and calculated values of hazards indices, it is concluded that the surveyed area is not a major source of radiation hazards and do not pose any health problem.
Radioprotection, 2009
CBPP Kakanj is one of the most important Coal Burning Power Plants in Bosnia and Herzegovina (producing power of 450 MW, waste storage site of 5 000 000 tons). Mapping of the measured gamma-dose rate has been performed with the goal of identifying the hot spots in the area of 3 × 3 km surrounding CBPP Kakanj, with special emphasis on the waste storage site (1 × 1 km). Maximum measured of the gammadose rate surrounding CBPP Kakanj was 140 nGy h −1 and in the area of waste storage site 210 nGy h −1. Average levels of natural radionuclide in agricultural soil samples in vicinity of CBPP Kakanj are: for 238 U is 41 ± 4 Bq kg −1 , 232 Th is 32 ± 1 Bq kg −1 , 226 Ra is 27 ± 2 Bq kg −1 and 40 K is 486 ± 9 Bq kg −1. Obtained results in soil-plant-animal products chain does not show significantly increased levels of natural radionuclides due to the fact that mentioned radionuclides, in general, have a low transfer factors in soilplant-animal products chain.
Journal of Physics: Conference Series, 2018
The Analysis of Natural Radioactivity content in coal wastes from Medan Industrial Area has been carried out by using Gamma Spectrometer with HP-Germanium detector. Coal wastes was collected from a pile of wastes in a plant which used two different origin of coal was Palembang and Kalimantan areas. The aim of this study to determine the content of activity concentration of natural radioactivity elements and to assess risk exposure to human and environment. The results of quantitative analysis of the activity concentration of natural radioactive elements from Palembang coal wastes of U-238, Th-232 and K-40 were 3640.60±593.70; 112.78±13.14 and 155.82±32.18 Bq/kg, respectively. Whereas for Kalimantan coal wastes the concentration of U-238, Th-232 and K-40 were obtained 1778.77±79.29; 52.00±2.27 and 160.10±5.92 Bq/kg, respectively. Risk assesment of the exposure to radiation gamma of the wastes to human and enviroment in the vicinity of area, was calculated as risk indeces. The average radium equivalent (Ra eq) was of 2760.4168 Bq/kg, the average of absorbed dose rate (D) was of 1275.0414 nGy/h, gamma index (γ i) was of 64.3468 and the average of annual effective dose was of 10.9022 mSv. All indeces were above average world values and therefore its suggested to suspend the use of the coal and the wastes. This was the preliminary study to measure the activity concentration of natural radioactivity in the study area.
Analysis of natural radionuclides in coal, slag and ash in coal-fired power plants in Serbia
Journal of Mining and Metallurgy, Section B: Metallurgy, 2011
The radioactivity monitoring in the ?Nikola Tesla?, ?Kolubara?, ?Morava? and ?Kostolac? coal-fired power plants was performed by the Radiation and Environmental Protection Laboratory, Vinca Institute of nuclear sciences in the period 2003-2010. Monitoring included the analysis of soil, water, flying ash, slag, coal and plants. This paper presents the results of the radioactivity analysis of coal, ash and slag samples. Naturally occurring radionuclides 226Ra, 232Th, 40K, 235U, 238U, and 210Pb as well as the man-made radionuclide 137Cs were determined by gamma spectrometry using HPGe detector. The concentrations of pairs of radionuclides were statistically tested to determine the correlation between them. Based on the obtained results, health effect due to the activity of these radionuclides was estimated via radium equivalent (Raeq), external hazard index (Hex), external gamma absorbed dose rate () and annual effective dose.
Behaviour of natural radionuclides in coal combustion
Radioprotection, 2009
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