Utilization Of Nuclear Energy Research Articles

Nitrogen-doped hierarchically porous carbon derived from biomass for efficient capture of iodine

Effectively capturing radioactive iodine formed during nuclear energy utilization is crucial for environment protection and human health. Herein, we present a facile and effective strategy to synthesize a nitrogen-doped hierarchically porous carbon from corn stalks for iodine capture in gaseous and liquid environment. The as-prepared carbon material possesses a hierarchically micro/mesopore structure with highly developed mesopores, a large specific surface area (1892.99 m2 g−1), and suitable nitrogen-doping (2.32 at.%). As a result, the carbon material exhibits efficient iodine capture performance, showing a large capture capacity of 3.14 g g−1 at 80 °C for iodine vapor and a fast removal rate of ∼97 % within 5 min for iodine aqueous solution, outperforming most of carbon-based materials for iodine capture reported in literatures. Thermodynamic and kinetic analyses reveal that the adsorption of iodine vapor conforms to the Langmuir model and pseudo-second-order model, respectively. Density functional theory calculation results indicate that the doped-nitrogen heteroatoms strengthen the interaction between iodine molecules and carbon, which can enhance the affinity for iodine molecules by forming a donor–acceptor complex through the donation of lone-pair electrons, thereby facilitating effective capture of iodine. This work develops a biomass-based porous carbon with potential to efficiently capture radioactive iodine.

Designing flexible TiO2/SrTiO3/BiOBr recyclable fiber membrane with spatial dual oxidation sites for photocatalytic uranium extraction under visible light

The utilization of nuclear energy generates a substantial volume of wastewater containing uranium, posing a significant threat to both aquatic ecosystems and human health. The current photocatalytic materials utilized for uranium extraction commonly exhibit insufficient redox capabilities, inefficient separation of photogenerated carriers, and challenging recovery. Therefore, recyclable TiO2/SrTiO3/BiOBr (TSB) dual Z-scheme heterojunction fiber membrane materials with dual oxidation sites were successfully synthesized, with advantages of rapid carrier separation and transfer and a broad photo-response range of the dual Z-scheme heterojunctions. Due to the presence of dual oxidation sites, TSB exhibited an exceptional uranium extraction performance, achieving a remarkable 98.9 % extraction rate without the need for sacrificial agents, which was 2.48, 1.79, and 3.34 times of those of ordinary TiO2, SrTiO3, and BiOBr, respectively. The extraction rate of uranium from TSB was 85 % after five cycles. Optical and photoelectric tests revealed that TSB reduced the bandgap width by 0.25 eV compared to that of TiO2, enhanced the fluorescence lifetime by 1.3 ns, lowered the electrical resistance, and higher optical current density, confirming the effective charge transport at the catalyst interfaces. The charge transfer routes in the TSB dual Z-scheme were confirmed by X-ray photoelectron spectroscopy and density functional theory. The potent oxidizing ·OH generated by TSB played a crucial role in facilitating the conversion of U(VI) into insoluble (UO2)O2·2H2O. In conclusion, this work provides a novel strategy for the design of dual Z-scheme heterojunctions and offers a new method for practical and recoverable uranium extraction.

Development of Small Modular Reactor iPWR Dynamics Simulator

Abstract In the energy transition era, nuclear power serves as a significant source of electricity with low emissions, contributing to approximately 10% of the world’s total electricity production. The advanced and distinct features of iPWR-type SMR in the field of nuclear power generation contribute to a greater safety margin. This opens up possibilities for extending the utilization of secure, environmentally friendly, and dependable nuclear energy across various energy sectors. Moreover, the public need to understand the technical performance of the iPWR. To improve understanding of iPWR’s technical performance, a simulator is developed. The simulator is developed to provide a comprehensive study of nuclear reactor transient behavior, to serve as an educational tool for students, and to demonstrate the safety features during accident scenarios. This article introduces a simulator that combines modules of neutronics, reactor thermal-hydraulics, and the NSSS. The simulator uses the design parameters of iPWR with a power capacity of 160 MWt that relies on natural convection. The proposed simulator was developed using LabVIEW software to perform the reactor dynamics calculations. Furthermore, hardware devices for controlling the simulator can be integrated to simulate the control room of an NPP. The calculation was based on the standard lumped parameter point kinetics and thermal-hydraulic equations. To simplify the process and reduce computational cost, several assumptions are incorporated into the equations, including one-group thermal neutron and constant gain thermal power. The simulator development yields preliminary data for reactor calculations, the graphical user interface (GUI) of the simulator, and the Virtual Instruments (VIs) comprising the reactor model. The reactor model comprises multiple components, each represented as a subVI within the LabVIEW environment. This simulator serves as an effective educational and dissemination tool for increasing public acceptance of NPP by providing insights into the behavior of the reactor and facilitating a better understanding of its operation, safety features, and potential benefits.

A self-organized sandwich structure of chromium nitride for ultra-long lifetime in liquid sodium.

The development of fast neutron reactors with improved efficiency and sustainability, being a tangible solution to the large-scale utilization of nuclear energy, serves as a critical step prior to the commercialization of fusion energy. These reactors use liquid metal coolants, which can weaken the durability of metallic components. Conventional design of protective coatings counts upon thermodynamics, which often overlooks the kinetic factors such as structural evolutions, resulting in deteriorated coating properties. Herein, we present a novel interface-engineering strategy involving the control of the phase transformation direction and interface diffusion reaction. Through iterations of self-organization, desired surfaces and interfaces can be achieved for materials used in harsh environments. Specifically, a CrN-coated steel sample with an interfacial Cr layer was designed and fabricated. After ultra-long (up to 6000 h) immersion in liquid sodium, the CrN/Cr coating structure was converted into a sandwich Cr2N/CrN/Cr2N structure dynamically. As a consequence, the coating system exhibited enhanced properties, namely increased surface hardness (by ∼36%), reduced coefficient of friction (by ∼13%), and enhanced interfacial adhesion (by ∼37%). Thus, the proposed strategy can guide the future design of robust coatings with ultra-long service life in harsh environments.

Construction of nitrogen-rich groups @ zirconium-based metal-organic frameworks for efficient iodine capture

Efficient capture of radioactive iodine serves as an inevitable demand for secure utilization of nuclear energy, environmental conservation, and human health. In this contribution, a series of iodine adsorbent materials Im@UiO-66 were fabricated by encapsulating imidazole (Im) molecules into the pore of a classical zirconium-based metal–organic frameworks UiO-66, employing a simple and feasible vapor-diffusion strategy. Compared with original UiO-66, the resulting composites achieved a significant enhancement in iodine capture performance. Particularly, Im@UiO-66-3 demonstrated outstanding iodine adsorption performance with capacities of 4.66 g g−1 for vapor and 915 mg g−1 for solution, which were 3.5 and 9.2 times of the original UiO-66, respectively. Moreover, the introduction of nitrogen through ligand encapsulation provided additional sites for iodine immobilization. The primary mechanism underlying this remarkable performance was identified as charge transfer between iodine and imidazole (Im) molecules. The research offers valuable insights for the design of high-efficiency iodine adsorbents.

Human intrusion dose assessment for the safe disposal of radioactive spent resin mixed waste at disposal facilities

This study explores the feasibility of safely disposing of spent resin mixed waste from which pure beta emitters(14C, 3H) have been removed 95 % at near-surface disposal facilities and evaluates the radiation dose to the public in the event of human intrusion after the management period of the disposal site. The decommissioning of Wolsong Unit 1, Korea's first commercial heavy water reactor, marks a critical juncture in the field of nuclear energy, highlighting the imperative for advancements in the methodologies of decommissioning, decontamination, and stewardship of mixed spent resin radioactive waste. To this end, six human intrusion scenarios are examined, and a cross-validation is performed using GENII and RESRAD-ONSITE simulation codes to confirm that the public dose criterion of 1 mSv/y is not exceeded under any of the scenarios. This result suggests that the safe disposal of waste from which beta radionuclides have been removed is possible, carrying significant implications for waste management and environmental protection. Such assessments provide scientific evidence for establishing waste disposal strategies and can serve as foundational data for the sustainable utilization of nuclear energy.

Effective capture of gaseous Se during spent nuclear fuel recycling using calcium oxide pellets: Optimization, performance, and practical implications

The continuous utilization of nuclear energy has led to the accumulation of spent nuclear fuel (SNF) containing uranium, transuranium, and fission products (FPs). Reprocessing and pyrochemical methods have shown the potential for SNF reuse, thereby reducing its environmental impact. Voloxidation, a pivotal step in SNF recycling, involves thermal treatment in an oxidizing atmosphere to enhance the reactivity. During voloxidation, Se-79, which is a FP with a long half-life, is released as SeO2 under oxidizing conditions, necessitating technologies to capture it. CaO pellets (CPs) were prepared to capture gaseous SeO2. The effects of operating conditions on SeO2 capture performance were investigated. The CP reacts strongly with SeO2 to form CaSeO3, exhibiting a high adsorption capacity of 17.5 mol kg−1 and > 99% efficiency at 700 °C. The mechanical strength and thermal stability assessments indicate suitability for practical applications. Depending on the flow rate, the CP required for SeO2 capture was estimated when processing 1 t of SNF, thereby contributing to the design of effective SeO2 capture systems for safe and sustainable nuclear waste management.

The economic and environmental assessment of alternative marine fuels and nuclear energy utilization on a floating power plant.

The paper aims to investigate the fuel and system options for a floating power plant (FPP) considering economic performance and the decarbonization goals of the International Maritime Organization. Various case studies have been assessed using a reference FPP, encompassing the instant and future retrofitting scenarios. The ready-to-use scenarios involve alternative fuel and organic Rankine cycle-based waste heat recovery system usage. Nuclear energy systems have been evaluated within the reference FPP since they are suitable candidates for achieving zero-carbon objectives and providing low-cost electricity. A simulation framework created in Python has calculated the fuel consumption regarding the power requirement and organized the approaches used in the study. An environmental model comparing the systems has been built to calculate upstream and operational emissions. The cost projection model for 2030 and 2050 has assessed the economic performance. Technique for Order of Preference by Similarity (TOPSIS) one of the multi-criteria decision-making approaches has ranked the systems considering the outcomes of economic and environmental models over the years. Findings demonstrate that the current fuel usage scenario of the FPP is not suitable both environmentally and economically. The other emissions can be near zero and greenhouse gases can be decreased by up to 15.95% using alternative fuels. Nuclear energy is a strong candidate to meet the 2050 targets, but its viability is largely based on economic performance.

Strategies to promote nuclear energy utilization in hydrogen production

The significant increase in harmful GHG emissions has led to dramatic global climatic changes. Thus, a need arises for clean, sustainable, economically viable energy sources. Prink hydrogen is the production of hydrogen using a nuclear energy source. No clear legislation regulates the utilization and operation of hydrogen in general and pink hydrogen in particular. This study analyzes nuclear energy regulations in various countries and regions and introduces a gap analysis in the nuclear field, comparing the under-established to the well-established regulatory bodies. This study utilized a harmonious blend of analytical tools utilizing both a gap analysis and an integrated decision-making methodology. Gap analysis showed a weak regulatory infrastructure, which hinders the adoption of pink hydrogen in some regions. Strategies were suggested in this study to address the identified weaknesses and threats linked to pink hydrogen technology to enhance energy security.

Research progress on microbial adsorption of radioactive nuclides in deep geological environments.

Due to the development and utilization of nuclear energy, the safe disposal of nuclear waste needs to be urgently addressed. In recent years, the utilization of microorganisms' adsorption capacity to dispose of radioactive waste has received increasing attention. When compared with conventional disposal methods, microbial adsorption exhibits the characteristics of high efficiency, low cost, and no secondary pollution. In the long term, microbial biomass shows significant promise as specific chemical-binding agents. Optimization of biosorption conditions, identification of rare earth element binding sites, and studies on the sorption capacities of immobilized cells provide compelling reasons to consider biosorption for industrial applications in heavy metal removal from solutions. However, the interaction mechanism between microorganisms and radioactive nuclides is very complex. This mini-review briefly provides an overview of the preparation methods, factors affecting the adsorption capacity, and the mechanisms of microbial adsorbents.

A scientometric review of knowledge domains on nuclear radiation

Nuclear energy is an important energy component to achieve the goal of “carbon peak and carbon neutrality”. Nuclear radiation is one of the hot spots in the development and utilization of nuclear energy. This study used bibliometric methods to gain a preliminary understanding of the knowledge system in the field of nuclear radiation and explored the network relationships of cooperation in the field of nuclear radiation. The literature data for the study were obtained from the Web of Science core collection database. All literature from 2008 to 2023 was downloaded, totalling 1602 articles. VOSviewer and CiteSpace were used to analyze several aspects such as article volume, keyword clustering and collaborative network relationships. The research showed that the years 2011–2014 and 2017–2020 were periods of vigorous literature development, with a sharp increase in the number of literature. In the collaborative network, the author collaborative network was divided into five different clusters, mainly dominated by Tsubokura, Masaharu and Yasumura, Seijiz. Research and development in various countries were uneven, and cooperation between underdeveloped national institutions in this field was even more limited. In the keyword clustering, five cluster models have been established, including the investigation and related treatment of nuclear radiation hazards, the Fukushima nuclear accident in Japan, research on nuclear radiation products, optical properties of nuclear radiation, and research on shielding materials. Recently, radiation shielding materials, photons and neutrons have become research hotspots. Through this study, we can gain a deeper understanding of the development status, cooperation networks, and cutting-edge research information in the nuclear field, which can serve as a reference for researchers.

Research progress on thermal aging of reactor pressure vessel steel

Nuclear energy is highly valued in many countries for its reliability, cleanliness and cost-effectiveness. Ensuring the safe development and utilization of nuclear energy has become crucial for addressing the global energy shortage and mitigating climate change. The reactor pressure vessel (RPV) is exposed to a high-temperature, high-corrosion and high-radiation environment, the RPV materials have a significant impact on the stability and safety of a nuclear power station. In this paper, the effects of long-term high-temperature hot aging on microstructure and mechanical properties of RPV steel, as well as the research progress in embrittlement mechanism and service life prediction, are reviewed. At the same time, the existing problems and further research directions of RPV steel are pointed out.

Harnessing Geothermal Energy Potential from High-Level Nuclear Waste Repositories

The disposal of high-level nuclear waste (HLW) has been one of the most challenging issues for nuclear energy utilization. In this study, we have explored the potential of extracting decay heat from HLW, taking advantage of recent advances in the technologies to utilize low-temperature geothermal resources for the co-generation of electricity and heat. Given that geothermal energy entails extracting heat from natural radioactivity within the Earth, we may consider that our approach is to augment it with an anthropogenic geothermal source. Our study—for the first time—introduces a conceptual model of a binary-cycle geothermal system powered by the heat produced by HLW. TOUGHREACT V3.32 software was used to model the heat transfer resulting from radioactive decay to the surrounding geological media. Our results demonstrate the feasibility of employing the organic Rankine cycle (ORC) to generate approximately 108 kWe per HLW canister 30 years after emplacement and a heat pump system to produce 81 kWth of high-potential heat per canister for HVAC purposes within the same timeframe. The proposed facility has the potential to produce carbon-free power while ensuring the safe disposal of radioactive waste and removing the bottleneck in the sustainable use of nuclear energy.

Design and preparation of WBX/Al composites for nuclear radiation protection

As the utilization of nuclear energy continues to expand, there is a growing focus on the development of lightweight and efficient nuclear shielding composites. In this paper, novel WBX/Al (x = 1, 2, 4) composites were designed based on shielding performance. The effects of reinforcement type, volume fraction, and material thickness on the 60Co and 137Cs γ-rays, fast and thermal neutron shielding performances were simulated. The results show that WB/Al composites offer better development potential compared to WB2/Al or WB4/Al composites. Additionally, a predictive model for the γ-ray shielding effectiveness of WB/Al composites, based on the areal density of tungsten, was proposed. The fabrication process involved mechanical ball milling and spark plasma sintering to fabricate 30 vol% WB/Al composites, with optimization of ball milling time, sintering temperature, and holding time. As a result, a novel nuclear radiation protection composite with uniform composition, a relative density of 97 %, and flexural strength of 527 MPa was acquired.

An Integrated Solution for Nuclear Power Plant On-Site Optimal Evacuation Path Planning Based on Atmospheric Dispersion and Dose Model

Safety in nuclear energy utilization is crucial. In the event of a radioactive release incident, coupled with meteorological uncertainties, a radioactive plume can impact personnel evacuation. This paper presents an integrated solution for radionuclide release accident assessment and emergency evacuation decision making. The solution consists of three processes: atmospheric dispersion calculation, dose calculation, and path planning. The individual processes are connected through data exchange, thus allowing users to choose specific models based on experience. The proposed scheme combination is the Gaussian plume model, the dose conversion factor method, and an improved Dijkstra’s path planning algorithm. This algorithm, combined with dispersion and dose results, weighs nodes using the moving expected dose, facilitating the path with minimum dose risk. A program for Atmospheric Diffusion and Dose Calculation (ADDC) is developed based on the recommended scheme. Advantages include ease of use, minimal data requirements, data accessibility, and efficient evacuation. Dose estimates and optimal evacuation routes can be obtained quickly and at very low cost in response to rapidly changing environmental conditions. In a case study at a Chinese planned nuclear plant, we consider a spent fuel pool water loss scenario, assessing dose risks from 2020 to 2022 meteorological statistics. In dose calculation, results reveal that during an SFP drying accident, the radiation dose in the core area (100 m away) can reach 30–150 mSv within 2 h, and at 500 m away, it can reach 5–15 mSv. The dose in all downwind directions can drop below 250 mSv within 60 m. In path planning, results reveal the program is capable of accurately and efficiently calculating the minimum dose evacuation route. The program’s path reduces the effective dose by up to 67.3% compared to the shortest route, enhancino safety, and guiding post-accident decision making and planning.

Nexus between Nuclear Energy, Economic Growth, and Greenhouse Gas Emissions in India

The escalating demand for fossil fuels in India has resulted in a significant strain on the environment due to the amplified emissions of greenhouse gases (GHGs). Nevertheless, India possesses a significant capacity for nuclear energy, as seen by its 22 operational nuclear reactors. This capacity holds promise for reducing GHG emissions. This research utilized a dataset spanning from 1969 to 2021 to examine the impact of nuclear energy utilization on GHG emissions. The study also aimed to verify the validity of the environmental Kuznets curve (EKC) hypothesis in India, employing the Autoregressive Distributive Lag (ARDL) model. The findings suggest that the EKC is applicable to India. Furthermore, it has been observed that a marginal increase of 1% in the use of nuclear energy leads to a reduction of GHG by 0.02% in the immediate term and 0.16% in the long term. This finding highlights the significance of expanding nuclear power as a crucial policy objective in order to attain environmentally friendly and sustainable economic development.

Harvesting the Vibration Energy of CdS for High‐Efficient Piezo‐Photocatalysis Removal of U(VI): Roles of Shape Dependent and Piezoelectric Polarization

Piezo‐photocatalysis could coalesce the advantages of mechanical vibration and solar energy perfectly to achieve high‐efficiency catalytic activity. Herein, the quintessential piezoelectric material CdS nanowires with different aspect ratios are precisely constructed and applied for piezo‐photocatalytic reduction of U(VI) for the first time. The ultrasonic (60 kHz, 100 W) induces piezoelectric potential to generate a 0.57 eV A−1 electric field, which is added to the direction of CdS (010) as a driving force to efficiently separate photogenerated charges. The alliance between piezoelectric effect and photocatalytic activity endows CdS NW‐3 with the fastest piezo‐photocatalytic rate under ultrasonic vibration and 5 W LED irradiation, and the relevant rate constant (0.042 min−1) is about 12 and 53.8 times than that of LED and ultrasonication. More importantly, 93.74% of U(VI) could be removed from natural uranium mine wastewater. Therefore, this piezo‐photocatalysis system that reduces U(VI) to easily separable (UO2)O2·2H2O(s) provides valuable input for disposal applications of radioactive wastewater and broadens the horizons of nuclear energy utilization toward the advancement of carbon neutrality.

Heat transfer characteristics of passive containment cooling system with equal height difference under steady-state conditions

In the nuclear energy utilization, the passive containment cooling system (PCCS) holds paramount importance, with its heat transfer performance standing as a critical aspect of nuclear safety. This study simulated the flow and heat transfer behaviors of PCCS with equal height difference by APROS software under a broad range of steady state operating conditions. At first, the flow pattern of natural circulation is categorized by phase state of flow through operational parameters. A criterion model of boundary of phase change is proposed with prediction deviation of less than ±25 %. Furthermore, the influence of various operation parameters such as temperature, non-condensable gas content, and pressure on the heat transfer behaviors of natural circulation was also revealed. A new heat transfer coefficient correlation for both single-phase and two-phase conditions is proposed with prediction deviation of ±15 %. Finally, the thermal stratification phenomenon in the containment vessel with non-condensable gas was investigated, indicating that local heat transfer characteristics in the upper region surpass those in the lower section on account of deposition of the non-condensable gas at bottom of the vessel.

Highly Selective Extraction of U(VI) from Solutions by Metal Organic Framework-Based Nanomaterials through Sorption, Photochemistry, and Electrochemistry Strategies.

With the rapid development of nuclear technology and peaceful utilization of nuclear energy, plentiful U(VI) not only is required to be extracted from solutions for a sustainable nuclear fuel supply but also is inevitably released into the surrounding environment to result in pollution and threaten human health. Thereby, realizing selective extraction of U(VI) from aqueous solutions is crucial for U(VI) pollution control and a sustainable nuclear industry. Metal organic frameworks (MOFs) have gained multidisciplinary attention due to their excellent properties including large specific surface areas, tunable pore structures, easy functionalization, etc. This Review comprehensively summarizes the research progress of MOFs and MOF-based materials on U(VI) removal from aqueous solutions by sorption, photocatalysis, electrocatalysis, membrane separation, etc. The efficient high extraction ability is dependent on the intrinsic properties of MOFs and the techniques used. The removal properties of MOF-based materials as adsorbents, photocatalysts, and electrocatalysts for U(VI) are discussed. Information about the interaction mechanisms between U(VI) and MOF-based materials are analyzed in-depth, including experiments, theoretical calculations, and advanced spectroscopy analysis. The removal properties for U(VI) of various MOF-based materials are assessed through different techniques. Finally, a summary and perspective on the direction and challenges of MOF-based materials and various pollutant removal technologies are proposed to provide some significant information on designing and fabricating MOF-based materials for environmental pollution management.

Nuclear Cogeneration of Methanol and Acetaldehyde from Ethylene Glycol Using Ionizing Radiation.

Despite offering low-carbon and reliable energy, the utilization of nuclear energy is declining globally due to high upfront capital costs and longer returns on investments. Nuclear cogeneration of valuable chemicals from waste biomass-derived feedstocks could have beneficial impacts while harnessing the underutilized resource of ionizing energy. Here, we demonstrate selective methanol or acetaldehyde production from ethylene glycol, a feedstock derived from glycerol, a byproduct of biodiesel, using irradiations from a nuclear fission reactor. The influence of radiation quality, dose rate, and the absorbed dose of irradiations on radiochemical yields (G-value) has been studied. Under low-dose-rate, γ-only radiolysis during reactor shutdown rate (<0.018 kGy min-1), acetaldehyde is produced at a maximum G-value of 8.28 ± 1.05 μmol J-1 and a mass productivity of 0.73 ± 0.06% from the 20 kGy irradiation of neat ethylene glycol. When exposed to a high-dose-rate (6.5 kGy min-1), 100 kGy mixed-field of neutron + γ-ray radiations, the radiolytic selectivity is adjusted from acetaldehyde to generate methanol at a G-value of 2.91 ± 0.78 μmol J-1 and a mass productivity of 0.93 ± 0.23%. Notably, utilizing 422 theoretical systems could contribute to 4.96% of worldwide acetaldehyde production using a spent fuel pool γ-ray scheme. This research reports G-values and production capacities for acetaldehyde for high-dose scenarios and shows the potential selectivity of a nuclear cogeneration process to synthesize chemicals based on their irradiation conditions from the same reagent.