Measurement of enhanced radium isotopes in oil production wastes in Turkey

Radiological assessment of the disposal of bulk oil NORM waste: Case study from Brazil

The oil and gas industries are the largest producers of NORM wastes that are continuously generated during production and extraction activities. In addition, an increasing trend is observed in waste production worldwide due to the decommissioning of oil platforms. The problem is that most of these wastes are in activity concentration levels above the exemption and the clearance limits and are being accumulated in storage sites because no repositories exist in Brazil for NORM wastes generated by oil industries. There are regulations for radioactive wastes and for the licensing of repositories for managing wastes with low and intermediate levels of radiation but the current regulations apply only to packaged wastes. Therefore an initial radiological assessment was carried out with the RESRAD-OFFSITE code to show that bulk NORM wastes (not packaged wastes) could be disposed of in repositories near the surface without causing additional risk to the public above the criteria used. The results can also support decision-making by the Regulatory Authority to change the current regulations and allow for the disposal of wastes in bulk form.

Radiochemical signature of radium-isotopes and some radiological hazard parameters in TENORM waste associated with petroleum production: A review study

Large amounts of TENORM waste (produced water, scale, and sludge) are created in oilfields around the world, presenting radiological risks to employees, the public, and the environment since activity concentrations of radioactive substances were above the exemption levels accredited by several authorities. Using the activity concentration of the radium-isotopes (²²⁶Ra and ²²⁸Ra) in the waste, we determined the 'fingerprint' as a radiochemical signature and some relevant 'radiological hazard parameters' in this review. The majority of the reported residues take the form of radio-contaminated (produced water, scale, and sludge) generated in Egypt's oilfields or elsewhere include radium isotope activity concentrations (^226,228Ra) that exceed the international exemption limit. The activity concentrations of ²²⁶Ra(²³⁸U-series) in produced water, scale, and sludge waste were 0.04-1,480 Bq/L, 1.1-2,015,000 Bq/kg, and 1-120,800 Bq/kg, respectively, whereas ²²⁸Ra (²³²Th-series) was 0.34-250 Bq/L, 1.8-1,428,000 Bq/kg, and 10-122,830 Bq/kg, respectively. The radioactivities of radium isotopes were found to be above the exemption values recognized by WHO, IAEA, IOGP, EC, and ICRP in 95, 82, and 58% of produced water, scale, and sludge waste, respectively. The ²²⁶Ra(²³⁸U)/²²⁸Ra(²³²Th) ratio, from the other hand, was estimated to be utilised as a 'radiochemical fingerprint', or signature in the reported TENORM residues. The radium isotopes ratio in produced water, scale, and sludge waste in Egypt's oilfields is 0.41-4.45 (av. 1.98 ± 1.37, coefficient of variation, COV %: ∼69%), 0.2-21.4 (av. 4.3 ± 4.7, ∼109%), and 1.4-52.2 (av. 9.6 ± 15.3, ∼159%), respectively. For produced water, scale, and sludge waste, the ²²⁶Ra/²²⁸Ra ratios are 0.12-9.1 (av. 1.43 ± 1.72, ∼120%), 0.2-159 (av. 7.78 ± 23.5, ∼302%), and 0.8-223.5 (av. 14.1 ± 45.4, ∼322%) in global oilfields. The radiological hazard parameters (I_g, I_a, E_◦, E_G, and ELCR) owing to radium isotopes or ²²²Rn in most scale and sludge residues, as well as a small percentage of produced water, are all over the allowed safe limits. Substantial differences in the radium isotopes ratio in the reported waste can be attributed to thier geological, chemical, physical, and/or operational constraints. However, from the different perspectives of remediation and/or radiation protection programs, these values can be employed as a guidance for organizations investing in oil and gas production.

Produced Water Treatment with Conventional Adsorbents and MOF as an Alternative: A Review

A large volume of produced water (PW) has been produced as a result of extensive industrialization and rising energy demands. PW comprises organic and inorganic pollutants, such as oil, heavy metals, aliphatic hydrocarbons, and radioactive materials. The increase in PW volume globally may result in irreversible environmental damage due to the pollutants' complex nature. Several conventional treatment methods, including physical, chemical, and biological methods, are available for produced water treatment that can reduce the environmental damages. Studies have shown that adsorption is a useful technique for PW treatment and may be more effective than conventional techniques. However, the application of adsorption when treating PW is not well recorded. In the current review, the removal efficiencies of adsorbents in PW treatment are critically analyzed. An overview is provided on the merits and demerits of the adsorption techniques, focusing on overall water composition, regulatory discharge limits, and the hazardous effects of the pollutants. Moreover, this review highlights a potential alternative to conventional technologies, namely, porous adsorbent materials known as metal-organic frameworks (MOFs), demonstrating their significance and efficiency in removing contaminants. This study suggests ways to overcome the existing limitations of conventional adsorbents, which include low surface area and issues with reuse and regeneration. Moreover, it is concluded that there is a need to develop highly porous, efficient, eco-friendly, cost-effective, mechanically stable, and sustainable MOF hybrids for produced water treatment.

High Specific Activity of Radium Isotopes in Baryte from the Czech Part of the Upper Silesian Basin—An Example of Spontaneous Mine Water Treatment

Radium-bearing barytes (radiobarytes) have been known since the beginning of the 20th century. They are mainly found as precipitates of low-temperature hydrothermal solutions. In anthropogenic environments, they frequently occur as crusts on oil industry equipment used for borehole extraction, in leachates from uranium mill tailings, and as a by-product of phosphoric acid manufacturing. Recently, we recognized Ra-rich baryte as a precipitate in the water drainage system of a bituminous coal mine in the Czech part of the Upper Silesian Basin. The precipitate is a relatively pure baryte, with the empirical formula (Ba0.934Sr0.058Ca0.051Mg0.003)Σ1.046S0.985O4.000. The mean specific activity of 226Ra was investigated by the two-sample method and it equals 39.62(22) Bq/g, a level that exceeds known natural occurrences. The values for 228Ra and 224Ra are 23.39(26) Bq/g and 11.03(25) Bq/g. The radium content in the baryte is 1.071 ng/g. It is clear that the Ra-rich baryte results from the mixing of two different mine waters—brines rich in Ba, Sr, and isotopes 226Ra and 228Ra and waters that are affected by sulfide weathering in mine works. When this mixing occurs in surface watercourses, it could present a serious problem due to the half-life of 226Ra, which is 1600 years. If such mixing spontaneously happens in a mine, then the environmental risks will be much lower and will be, to a great, extent eliminated after the closure of the mine.

Characterization and radiological impacts assessment of scale TENORM waste produced from oil and natural gas production in Egypt

This study aims to identify the analytical and radiological characterization of scale TENORM waste produced from oil and natural gas productions in the western desert in Egypt and evaluates their radiological impacts. The mean activity concentration of ²³⁸U, ²²⁶Ra, ²¹⁰Pb, ²²⁸Ra, ²²⁴Ra, and ⁴⁰K measured in scale TENORM samples is 660 ± 63, 1979 ± 435, 1399 ± 211, 645 ± 104, 794 ± 116, and 556 ± 86 Bq/kg, respectively. Radiological hazard parameters (Ra_eq, Hex, Hin, etc.) were estimated form the scale TENORM waste sample. All the calculated hazard parameters were found greater than the permissible and recommended safe levels. So the exposure to radiations released from the accumulation of the petroleum scale TENORM waste may cause health risks to the operators and who inhale radioactive radon gases and/or ingest contaminants by radiotoxic nuclides of U, Th, Ra, and Pb. Also, the risks may be extended to the near and/or the general environment.

Testing of the radon tightness of beakers and different types of sealing used in gamma-ray spectrometry for 226Ra concentration determination in NORM

The presence of radium is common in the natural environment. However, some human activities lead to the production of large amounts of waste and by-product containing elevated concentrations of radium. Several methods for the determination of radium isotopes exist. The common use of gamma-ray spectrometry is justified by several of its advantages: it is a non-destructive method, easy, it is a time- and cost-effective procedure of preparing a sample and provides a reasonable time of measurement. The major disadvantages of direct measurements of radium are its weak yields γ-line 186.2 keV (3.59%) and, additionally, an interference with ²³⁵U direct line 185.7 keV. There is an indirect method of measuring radium. The method uses the daughter radionuclides of radon: ²¹⁴Pb and ²¹⁴Bi. The problem is radon escape from the measurement container. The article describes the tests of radontightness of various types of containers and different types of sealing. In frame of performed measurements, not sufficient tightness of typical containers used in laboratories was found.

Concentrations of TENORMs in the petroleum industry and their environmental and health effects

Crude oil and its products and wastes are among the significant sources of naturally occurring radioactive materials (NORMs). These materials may be enhanced to high levels due to technological and human activities, which are called technologically enhanced naturally occurring radioactive materials (TENORMs). Thus, the average radioactivity of these radionuclides sometimes exceeds the exemption level of 10 000 Bq kg⁻¹, which is recommended by the IAEA's safety standards. TENORMs in the oil and gas industry may generate greater radioactivity levels, which eventually represents potential environmental and health risks. This will require continuous attention by monitoring and surveillance during routine processes in the petroleum industry. In this paper, a comprehensive review of the published literature is conducted to evaluate the TENORM concentrations in the oil and gas industry. Moreover, their environmental and health hazards in different regions of the world are discussed.

Crude oil and its products and wastes are among the significant sources of naturally occurring radioactive materials (NORMs).

Risk of bone tumors in children and residential proximity to industrial and urban areas: New findings from a case-control study

Few epidemiologic studies have explored risk factors for bone tumors in children, and the role of environmental factors needs to be analyzed. Our objective was to ascertain the association between residential proximity to industrial plants and urban areas and risk of bone tumors in children, taking into account industrial groups and toxic pollutants released. A population-based case-control study of childhood bone cancer in Spain was carried out, covering 114 incident cases obtained from the Spanish Registry of Childhood Tumors (between 1996 and 2011), and 684 controls individually matched by sex, year of birth, and autonomous region of residence. Distances from the subject's residences to the 1271 industries and the 30 urban areas (towns) with ≥75,000 inhabitants located in the study area were computed. Unconditional logistic regression models were fitted to estimate odds ratios (ORs) and 95% confidence intervals (95%CIs) for categories of distance (from 1km to 3km) to industrial and urban areas, with adjustment for matching variables and sociodemographic indicators. Excess risk (OR; 95%CI) of bone tumors in children was detected for children close to industrial facilities as a whole (2.33; 1.17-4.63 at 3km) - particularly surface treatment of metals (OR=2.50; 95%CI=1.13-5.56 at 2km), production and processing of metals (OR=3.30; 95%CI=1.41-7.77 at 2.5km), urban waste-water treatment plants (OR=4.41; 95%CI=1.62-11.98 at 2km), hazardous waste (OR=4.63; 95%CI=1.37-15.61 at 2km), disposal or recycling of animal waste (OR=4.73; 95%CI=1.40-15.97 at 2km), cement and lime (OR=3.89; 95%CI=1.19-12.77 at 2.5km), and combustion installations (OR=3.85; 95%CI=1.39-10.66 at 3km)-, and urban areas (4.43; 1.80-10.92). These findings support the need for more detailed exposure assessment of certain toxics released by these facilities.