A systematic study of uranium in groundwater and its correlation with other water quality parameters

A parametric investigation was carried out to estimate the Uranium concentration and other associated water quality parameters for the groundwater in Deoghar district, Jharkhand. Total 150 groundwater samples have been collected from dig wells, hand pumps, tube wells, etc. for the pre and post-monsoon seasons. A Quantalase Uranium analyzer was used to measure the uranium concentration. The distribution of pH, TDS, DO, nitrate, sulfate, uranium along with the radiation has been determined. It was found that the uranium concentration in groundwater varies from 0.10 to 11.30ppb in pre-monsoon and 0.15–6.50ppb in the post-monsoon which is well below the normal tolerance limit (i.e.30 μg/l WHO). This low availability of Uranium has been attributed due to the existence of a lesser number of rocks containing uranium as a source in that area. An attempt has been made to correlate the uranium concentration with the water quality parameters for both seasons. The correlation data reveals that ORP, nitrate, phosphate, calcium, and magnesium show a positive correlation with uranium concentration for both seasons on the other hand TDS, EC, temperature, DO, fluoride, and chloride show negative correlation. The positive correlation implies that uranium may be present in groundwater as a dissolved salt of these parameters. Comparative studies for the parameters have been done for both the seasons and various factors have been discussed for the occurrence of the same. The annual effective dose associated with the ingestion of uranium by the population of the region has been estimated using USPEA equations.

Radon Monitoring by Alpha Track Detection Using Cn–85 Plastic Track

Radon sources can be found in external and internal radiation. Lead pencil (LP) is often used for drawing, sketching, etc. regardless of age nowadays. Paracetamol (PC) is commonly used around the world especially to treat fever, headache, menstrual pain, and common pain. Hence, the aim is to study the procedures for determining the radon gas comes out from different types of lead pencil and paracetamol. Eight and five samples were collected from different companies of lead pencil and paracetamol, respectively. The samples were measured using the sealed technique in cylindrical plastic containers with CN–85 detectors. After irradiation, the detectors were chemically etched using 2 N sodium hydroxide (NaOH) solution at a temperature of 70 ºC for 62 min. The alpha track density on the surface of detectors was measured using an optical microscope at a magnification of 100×. Tracks on detectors were counted using Image software. Radon concentration values including all samples in this study are within the limits of international which is 1000 Bq/m3. The concentration of radium in LP and PC samples are lower than those reported in previous study. The result of the uranium concentration of both samples is quite low compared with the allowed limit which is 11.7 ppm. Annual effective dose levels are all below the dose limit which is 10 mSv/y. Lastly, there was a linear relationship between radium activity and radon exhalation rate. Therefore, using LP and eating PC cause no danger to humans. All results showed in this study are within internationally permissible limits, and therefore not a threat to human health.

Studies on uranium recovery from a U-bearing Radoniów Dump

This work reports the possibility of uranium recovery from a post-mining uranium ore dump in Poland by a bioleaching method. The studies were conducted on the dump leaching model with the mass of 570 kg of uranium bearing mineral material from Radoniów pile and in the periodic bioreactor with a work volume of 80 dm3 and with mechanical mixing and aeration of the charge. The uranium concentration in the examined material was about 800 ppm. In this process, the consortium of microorganisms isolated from former mines was used. It was composed of the following microorganisms: Bacillius, Pseudomonas, Sphingomonas, Thiobacillus, Halothiobacillus, Thiomonas, and Geothrix. The efficiency of the uranium bioleaching process was 98% in the reactor, and a yield of 70% was obtained in the dump leaching model. The post-leaching solution contained significant amounts of uranium ions that were separated in two stages: (1) by ion chromatography and then (2) by a two-step precipitation method. The resulting solution was a source of ammonium diuranate, the precursor of yellowcake (uranium oxides).

Determination of Uranium Concentration in Blood Samples for Patients with Kidney Failure in Salah din Governorate

Analysis of human biological samples, such as blood, is generally used to verify human exposure to uranium. The uranium content in the blood of patients with kidney disease in Salah al-din governorate was determined using the Fission Track Analysis (FTA) of the detector CR39. Uranium concentrations of blood samples taken from kidney failure patients ranged between 1.636 ppb to7.477 ppb, with a mean value of 5.496 ppb. And the health group values ranged between 0.301 ppb to 2.332 ppb with a mean value 1.089 ppb.

Investigating Radioactive Content in Various Commercially available Flour Samples in Local Iraqi Markets

The study was conducted to assess the radioactivity of alpha concentration of different samples of flour in Karbala mills and some samples in local Iraqi markets. Alpha sensitive CR-39 plastic paths detectors commonly know as "Solid State Nuclear paths Detectors" were used measuring the concentrations of uranium, efficaious radium content, and ratio of radon. The results indicate that the exhalation levels of mass and surface radon were between 0.214-0.549 mBq/kg.h, and 4.35 -11.185 mBq/m2.h, respectively, with an mediam of 0.385 mBq/kg.h and 7.691 mBq/m2.h. The effective radium content values range from 28 to 78 mBq/kg with an mediam value of 51.06 mBq/kg, respectively. The concentration of uranium values ranges from 0.334 to 0.858 Bq/kg, with a mean value of 0.602 Bq/kg. The measurements of the radon, radium, and uranium concentration in each sample are significant in terms of health safeguard point of view. Hence, easy, and accurate techniques of analysis are highly demanded.

Computational simulation and modelling of uranium extraction using tributylphosphate through membrane extractor

Non-disperse solvent extraction is an effective technique for the extraction of metal ions from aqueous solution. In this study, uranium extraction using n-dodecane solvent containing tributylphosphate extractant in a membrane contactor was investigated. A 2D mathematical model was developed for the fluid flow and mass transfer in the hollow fibre membrane extractor. The equations of the created model were solved using the finite element method. The uranium concentration distribution in the extractor at different extractant concentrations as well as feed acidity was studied. The results showed that there is reasonable good agreement between experimental uranium extraction and modelling outputs at different extractant concentrations. Increasing extractant concentration from 5 to 30% led to the enhancement of uranium extraction from 2.60 to 34.13%. Also, there was an increase in the uranium extraction with increasing feed acidity in the range of 1–3 M. Furthermore, based on the radial uranium concentration distribution, it was found that the main mass transfer resistance in the system was microporous membrane section. Finally, it was obtained that the uranium extraction efficiency could be improved significantly by increasing porosity-to-tortuosity ratio. It was concluded that the membrane specification plays the most important role as the dominant mass transfer resistant was in the membrane subdomain.

A peep into the state of ground water quality in the district of Tiruvannamalai, Tamil Nadu, India, from a radiological and chemical toxicity perspective

Uranium concentration in the ground water samples from the district of Tiruvannamalai, Tamil Nadu, was measured using an LED fluorimeter. All the samples were qualified as potable water from the radiological perspective. Though some samples showed mild chemical toxicity, they are still safe for ingestion. Different risk coefficients were calculated, and they were compared with recommended safety limits specified by various agencies. Software tools such as QGIS 15, GraphPad Prism 8 and Surfer 15 were employed for developing maps and plots.

Evolution of the uranium concentration in dissolution experiments with Cr-(Pu) doped UO2 in reducing conditions at SCK CEN

Cr-doped UO2-based model materials were prepared at SCK CEN, mimicking modern LWR fuels, to understand the influence of Cr doping on the spent fuel dissolution behaviour in geological repository conditions. Tests were carried out with four model materials: depleted UO2, Cr-doped depleted UO2, Pu-doped UO2 and Pu-Cr-doped UO2. Static dissolution experiments have been performed up to 4 months in autoclaves under 10 bar H2 pressure with a Pt/Pd catalyst in media at pH 13.5 and at pH 9. The Cr-doping appeared to reduce the U concentrations by a factor 6 at pH 13.5, but it had no or not much effect at pH 9. Graphic abstract

Release of Uranium from Uraninite in Granites Through Alteration: Implications for the Source of Granite-Related Uranium Ores

Uraninite is the main contributor to the bulk-rock uranium concentration in many U-rich granites and is the most important uranium source for granite-related uranium deposits. However, detailed textural and compositional evolution of magmatic uraninite in granites during alteration and associated uranium mobilization have not been well documented. In this study, textures and geochemistry of uraninites from the Zhuguangshan batholith (South China) were investigated by scanning electron microscopy (SEM) and electron probe microanalysis (EPMA). The geochemical data indicate that the Longhuashan and Youdong plutons are peraluminous leucogranite, the Changjiang pluton is highly fractionated high-K calc-alkaline granite, and the Jiufeng pluton belongs to a high-K calc-alkaline association. Uraninites from the Longhuashan and Youdong granites have lower concentrations of ThO2 (0.9–4.0 wt %) and rare earth elements (REE)2O3 (0.1–1.0 wt %) than those from the Changjiang and Jiufeng granites (ThO2 = 4.4–7.6 wt %, REE2O3 = 0.7–5.1 wt %). Uraninites observed in the Longhuashan, Youdong, Changjiang, and Jiufeng granites yielded chemical ages of 223 ± 3, 222 ± 2, 157 ± 1, and 161 ± 2 Ma, respectively. The samples (including altered and unaltered) collected from the Longhuashan, Youdong, and Changjiang granites are characterized by highly variable whole-rock U concentrations of 6.9 to 44.7 ppm and Th/U ratios of 0.9 to 7.0, consistent with crystallization of uraninite in these granites being followed by uranium leaching during alteration. Alteration of uraninite, indicated by altered domains developing microcracks and appearing darker in backscattered electron (BSE) images compared to unaltered domains, results in the incorporation of Si and Ca and mobilization of U. In contrast, the least altered samples of the unmineralized Jiufeng granite have low U concentrations (5.3–16.4 ppm) and high ΣREE/U (13.6–49.4) and Th/U ratios (2.1–5.6), which inhibit crystallization of uraninite, as its crystallization occurs when the U concentration is high enough to exceed the substitution capacity of other U-bearing minerals. These results indicate that the Longhuashan, Youdong, and Changjiang granites were favorable uranium sources for the formation of uranium deposits in this area. This study highlights the potential of uraninite alteration and geochemistry to assist in deciphering uranium sources and enrichment processes of granite-related uranium deposits.