Nuclear-based Hydrogen Production Research Articles

A study on integrated HTR-PM driven hydrogen production using thermochemical cycles

This present study aims to design a nuclear-based hydrogen production system by using the three- and four-step magnesium-chloride cycles, and compares the three-step magnesium-chloride cycle integrated nuclear-based system and the four-step magnesium-chloride cycle integrated nuclear-based system. Within the scope of this study, four units of high-temperature gas-cooled-pebble bed modular nuclear reactor are employed, where a total of 1 GW thermal energy (heat) is secured from these four reactors. All of the heat generated by the reactors is used to drive the power generation and hydrogen production cycles. The proposed system, along with its cycles and processes, are examined by using mass, energy, entropy, and exergy balance equations. The modeling and simulations for the three- and four-step magnesium-chloride cycles are carried out via the Aspen Plus software package. The results are compared for two hydrogen production methods, and sensitivity analysis is assessed for various steam/MgCl2 ratios, as well as different reactor temperatures and pressures for each reaction in the cycles. While the three-step magnesium-chloride cycle integrated nuclear-based system produces 2.43 kg/s hydrogen, 2.13 kg/s hydrogen is produced by the four-step magnesium-chloride cycle integrated nuclear-based system. As a consequence of this present study, energy and exergy efficiencies are calculated as 54.2% and 60.9% for the three-step magnesium-chloride cycle, while these values are 48.0% and 54.0% for the four-step magnesium-chloride cycle. Additionally, while the energy and exergy efficiencies of the three-step magnesium-chloride cycle integrated overall system are 29.2% and 40.3%, these values are 25.6% and 35.2% for the four-step magnesium-chloride cycle integrated system, respectively.

Design and construction of fluid-to-fluid scaled-down small modular reactor platform: As a testbed for the nuclear-based hydrogen production

This paper presents the construction results and design of the UNIST Reactor Innovation platform for small modular reactors as a versatile testbed for exploring innovative technologies. The platform uses simulant fluids to simulate the thermal-hydraulic behavior of a reference small modular reactor design, allowing for cost-effective design modifications. Scaling analysis results for single and two-phase natural circulation flows are outlined based on the three-level scaling methodology. The platform's capability to simulate natural circulation behavior was validated through performance calculations using the 1-D system thermal-hydraulic code-based calculation. The strategies for evaluating cutting-edge technologies, such as the integration of a solid oxide electrolysis cell for hydrogen production into a small modular reactor, are presented. To overcome experimental limitations, the hardware-in-the-loop technique is proposed as an alternative, enabling real-time simulation of physical phenomena that cannot be implemented within the experimental facility's hardware. Overall, the proposed versatile innovation platform is expected to provide valuable insights for advancing research in the field of small modular reactors and nuclear-based hydrogen production.

Technology Development for Hydrogen Production Using Nuclear Energy

Nuclear energy is a low-carbon energy source which can provide both electricity and high-temperature heat. Nuclear-based hydrogen production offers a unique opportunity to mitigate carbon emissions. Canadian Nuclear Laboratories (CNL) has been actively developing technologies for nuclear hydrogen production. This poster will highlight CNL’s capability and achievements on the Cu-Cl thermochemical process (CNL trademarked as HCuTECTM) and Solid oxide electrolysis (SOE).HCuTECTM has four main steps in the process: Electrolysis, Separation, Hydrolysis and Thermolysis. The maximum temperature of the HCuTECTM process is 530 oC, which is lower than other thermochemical processes and makes its coupling with some small modular reactors and the supercritical water nuclear reactor ideal since these reactors can supply heat above 600 oC. CNL has extensively studied these individual steps and demonstrated an integrated laboratory system (shown in Figure 1) with a hydrogen production capacity of 100 g/d. CNL is interested in scaling up the process with industrial partners.SOE is also being researched and advanced for hydrogen and clean fuel production at CNL. Current effort is focused on the materials development for oxygen conducting cells. Several CNL cells were made with in-house materials and tested on single cell stations. Preliminary results of CNL cells showed very promising performance for hydrogen production. In the meantime, CNL is assessing the economic benefit of different options to integrate SOE with high-temperature nuclear reactors for both hydrogen and clean fuel production. Figure 1

The upper thermal efficiency and life-cycle environmental assessment of nuclear-based hydrogen production via splitting H2S and CO2

It is proposed to develop a novel thermochemical cycle using nuclear energy to decompose H2S and CO2, thus producing H2 and CO from acidic gas in petrochemical or coal chemical industries, reducing CO2 emissions and promoting sustainable energy development. The upper limits and significant energy-consuming steps were determined based on two chemical routes of the thermochemical cycle systems 1 and 2. When the enthalpy of the H2S oxidation reaction served as part of the circulating energy input, the values for system 1 and system 2 were 38.7% and 34.3%, respectively. However, if only external energy is considered to satisfy the heat and work required to run the reaction and pump, the thermal efficiency rises to 58.4% and 61.2%, respectively. The life cycle assessment (LCA) was used to investigate the environmental effect of the hydrogen generation process base on the upper thermal efficiency in this study, and the results of the LCA are stated in terms of global warming potential (GWP) and acidification potential (AP). The GWP of systems 1 and 2 was calculated as 2.59 kg CO2-eq/kg H2, 2.54 kg CO2-eq/kg H2, The AP of systems 1 and 2 was calculated as 7.48 g SO2-eq/kg H2 and 9.08 g SO2-eq/kg H2, respectively. This paper assesses the environmental effect of two different hydrogen systems used in manufacturing various subsystems in GWP and AP, and compares them to the life cycle of other hydrogen production pathways.

An assessment study on various clean hydrogen production methods

In this study, an assessment study using the life cycle impact analysis of renewable and nuclear-based hydrogen production methods is conducted for possible implementation of hydrogen energy projects. The processes starting from the energy production, energy required for the hydrogen production, hydrogen transportation, and utilizing hydrogen at the refueling station are evaluated. The three methods, namely alkaline electrolysis, proton exchange membrane electrolysis, and the Cu–Cl cycle are selected as clean hydrogen production methods. Also, the potential environmental effects of using hydrogen to utilize fuel cell electric buses are investigated by comparing them with diesel buses. Accordingly, the Cu–Cl cycle itself provides the most environmentally friendly result with 0.86 kg CO2 eq./kg H2 when both energy and heat are considered as primary commodities from renewable energy sources. However, the electrolysis methods also provide better results than conventional hydrogen production. By comparison, conventional hydrogen production resulted in 7.95 kg CO2 eq./kg H2. The emissions of FCEBs utilizing the hydrogen from clean energy sources vary between 0.016 and 0.025 kg CO2 eq./p⋅km. However, even though upstream emissions are low in diesel buses, they have a GWP value of approximately 0.09 kg CO2 eq./p⋅km during operation.

Life cycle assessment of nuclear-based hydrogen and ammonia production options: A comparative evaluation

In this study, nuclear energy based hydrogen and ammonia production options ranging from thermochemical cycles to high-temperature electrolysis are comparatively evaluated by means of the life cycle assessment (LCA) tool. Ammonia is produced by extracting nitrogen from air and hydrogen from water and reacting them through nuclear energy. Since production of ammonia contributes about 1% of global greenhouse gas (GHG) emissions, new methods with reduced environmental impacts are under close investigation. The selected ammonia production systems are (i) three step nuclear Cu–Cl thermochemical cycle, (ii) four step nuclear Cu–Cl thermochemical cycle, (iii) five step nuclear Cu–Cl thermochemical cycle, (iv) nuclear energy based electrolysis, and (v) nuclear high temperature electrolysis. The electrolysis units for hydrogen production and a Haber–Bosch process for ammonia synthesis are utilized for the electrolysis-based options while hydrogen is produced thermochemically by means of the process heat available from the nuclear power plants for thermochemical based hydrogen production systems. The LCA results for the selected ammonia production methods show that the nuclear electrolysis based ammonia production method yields lower global warming and climate change impacts while the thermochemical based options yield higher abiotic depletion and acidification values.

Monte-Carlo-simulation-based performance analysis of the heat transfer process in nuclear-based hydrogen production based on Cu[sbnd]Cl cycle

As a crucial step in nuclear-based hydrogen production CuCl cycle, the performance analysis of the heat transfer processes is of paramount importance. However, as a newly built system, the major obstacle of applying standard performance analysis methods to the heat transfer process is the sparse data, i.e., there is not sufficient experimental data available for a systematic performance analysis. In this research, a Monte-Carlo-Simulation-based (MCS-based) performance analysis method is developed, and it is demonstrated that this method can be used effectively to tackle the problems caused by sparse data in the heat transfer processes. In this paper, the details of the heat transfer process in a nuclear-based hydrogen production based on a four-step CuCl cycle are discussed first. Afterwards, modeling of the heat transfer process for MCS-based performance analysis is provided. Finally, the confidence interval of the simulation results is obtained. This method forms the basis for the future study of reliability of nuclear-based hydrogen production.

Genetic-algorithm-based fault detection of the heat transfer process in nuclear-based hydrogen production based ON Cu–Cl cycle

In the heat transfer process of nuclear hydrogen production system based on a 4-step Cu–Cl cycle, there are three major varying temperatures, namely room temperature, hydrolysis temperature and oxygen decomposition temperature. The heat requirement of the system will change with the temperatures. Therefore, it is important to identify the optimal ranges of the varying temperatures to make sure the heat requirement will be satisfied by the heat from a nuclear power plant, when the temperatures fluctuating in the optimal ranges. Genetic-algorithm-based Monte Carlo simulation method is developed in this paper to identify the optimal ranges. This method is able to obtain the optimal ranges through random sampling. The final result indicates that GA-based MCS method can be applied to identify the optimal ranges of the varying temperatures in the heat transfer process, and the ranges are highly trustable.

Life cycle assessment of nuclear-based hydrogen production via a copper–chlorine cycle: A neural network approach

A comparative environmental study is reported of nuclear-based hydrogen production using thermochemical water decomposition cycles. The investigation uses a life cycle assessment (LCA) as is an analytical tool to evaluate and reduce the environmental impact of the system or product. The LCA results are presented in terms of acidification potential and global warming potential. Since LCA often utilizes software to model and analyse the system, an artificial neural network (ANN) method can be advantageous. Here, an ANN method is applied to a nuclear-based hydrogen production system. Using an ANN method in this study eliminates the need to use LCA software separately and facilitates the determination of the impacts of altering input parameters of a system (e.g., heat, work, production capacity and plant lifetime). The neural network approach to identify the best system option, consistent with LCA software results, is developed here using ten neurons in the hidden layers.

Environmental impact assessment of nuclear assisted hydrogen production via Cu–Cl thermochemical cycles

Abstract The variation of environmental impacts with the efficiency of a hydrogen plant and the thermal output of a nuclear plant are studied for nuclear-based hydrogen production using three-, four- and five-step Cu–Cl cycles for thermochemical water splitting (TWS). Results are presented, on the basis of 1 kg hydrogen production, for two impact categories: global warming potential (GWP) and acidification potential (AP). Environmental impacts are evaluated with several approaches. First, environmental effects are calculated by varying the thermal output ratio, which represents the thermal energy used in Cu–Cl cycle divided by the total thermal energy output of nuclear plant, from 0.1 to 1. The results show that GWP can be decreased from 3.32 to 0.346 kg CO2-eq for the five-step cycle. Second, the hydrogen plant efficiency is altered from 0.34 to 0.65 to examine the corresponding change in environmental impacts. Increasing the hydrogen plant efficiency to 0.65 decreases the GWP to 0.4 kg CO2-eq and the AP to 2.1 × 10−3 kg SO2-eq.

Exergetic life cycle assessment of a hydrogen production process

Exergetic life cycle assessment (ExLCA) is applied with life cycle assessment (LCA) to a hydrogen production process. This comparative environmental study examines a nuclear-based hydrogen production via thermochemical water splitting using a copper–chlorine cycle. LCA, which is an analytical tool to identify, quantify and decrease the overall environmental impact of a system or a product, is extended to ExLCA. Exergy efficiencies and air pollution emissions are evaluated for all process steps, including the uranium processing, nuclear and hydrogen production plants. LCA results are presented in four categories: acidification potential, eutrophication potential, global warming potential and ozone depletion potential. A parametric study is performed for various plant lifetimes. The ExLCA results indicate that the greatest irreversibility is caused by uranium processing. The primary contributor of the life cycle irreversibility of the nuclear-based hydrogen production process is fuel (uranium) processing, for which the exergy efficiency is 26.7% and the exergy destruction is 2916.3 MJ. The lowest global warming potential per megajoule exergy of hydrogen is 5.65 g CO2-eq achieved a plant capacity of 125,000 kg H2/day. The corresponding value for a plant capacity of 62,500 kg H2/day is 5.75 g CO2-eq.

Potential thermochemical and hybrid cycles for nuclear-based hydrogen production

This paper discusses some potential low-temperature thermochemical and hybrid cycles for nuclear-based hydrogen production and considers them as a sustainable option for hydrogen production using nuclear process/waste heat and off-peak electricity. We also assess their thermodynamic performance through energy and exergy efficiencies. The results show that these cycles have good potential and become attractive due to their high overall efficiencies 50% based on a complete reaction approach. The copper–chlorine cycle appears to be a highly promising cycle for nuclear-based hydrogen production in this regard. Copyright © 2010 John Wiley & Sons, Ltd.

Dynamic flowgraph modeling of process and control systems of a nuclear-based hydrogen production plant

Modeling and analysis of system reliability facilitate the identification of areas of potential improvement. The Dynamic Flowgraph Methodology (DFM) is an emerging discrete modeling framework that allows for capturing time dependent behaviour, switching logic and multi-state representation of system components. The objective of this research is to demonstrate the process of dynamic flowgraph modeling of a nuclear-based hydrogen production plant with the copper–chlorine (Cu–Cl) cycle. Modeling of the thermochemical process of the Cu–Cl cycle in conjunction with a networked control system proposed for monitoring and control of the process is provided. This forms the basis for future component selection.

Life Cycle Assessment of Hydrogen Production Using Nuclear Energy: An Application Based on Thermochemical Water Splitting

A life cycle assessment of nuclear-based hydrogen production using thermochemical water splitting is conducted. The copper-chlorine thermochemical cycle is considered, and the environmental impacts of the nuclear and thermochemical plants are assessed. Environmental impacts are investigated using CML-2001 impact categories. The nuclear plant and the construction of the hydrogen plant contribute significantly to the total environmental impacts. The environmental impacts of operating the hydrogen production plant contribute much less. Changes in the inventory of materials or chemicals needed in the thermochemical plant do not affect significantly the total impacts. Improvement analysis suggests the development of more sustainable processes, particularly in the nuclear plant and construction of the hydrogen production plant.

Nuclear-based hydrogen production with a thermochemical copper-chlorine cycle and supercritical water reactor: equipment scale-up and process simulation

SUMMARY Issues related to equipment scale-up and process simulation are described for a thermochemical cycle driven by nuclear heat from Canada's proposed Generation IV reactor (Super-Critical Water-Cooled Reactor; SCWR), which is a CANDU derivative using supercritical water cooling. The copper–chlorine (Cu-Cl) cycle has been identified by Atomic Energy of Canada Limited as the most promising cycle for thermochemical hydrogen production with SCWR. Water is decomposed into hydrogen and oxygen through intermediate Cu-Cl compounds. This article outlines the challenges and design issues of hydrogen production with a Cu-Cl cycle coupled to Canada's nuclear reactors. The processes are simulated using the Aspen Plus process simulation code, allowing the cycle efficiency and possible efficiency improvements to be examined. The results are useful to assist the development of a lab-scale cycle demonstration, which is currently being undertaken at the University of Ontario Institute of Technology in collaboration with numerous partners. Copyright © 2010 John Wiley & Sons, Ltd.

Coupling of copper–chloride hybrid thermochemical water splitting cycle with a desalination plant for hydrogen production from nuclear energy

Energy and environmental concerns have motivated research on clean energy resources. Nuclear energy has the potential to provide a significant share of energy supply without contributing to environmental emissions and climate change. Nuclear energy has been used mainly for electric power generation, but hydrogen production via thermochemical water decomposition provides another pathway for the utilization of nuclear thermal energy. One option for nuclear-based hydrogen production via thermochemical water decomposition uses a copper–chloride (Cu–Cl) cycle. Another societal concern relates to supplies of fresh water. Thus, to avoid causing one problem while solving another, hydrogen could be produced from seawater rather than limited fresh water sources. In this study we analyze a coupling of the Cu–Cl cycle with a desalination plant for hydrogen production from nuclear energy and seawater. Desalination technologies are reviewed comprehensively to determine the most appropriate option for the Cu–Cl cycle and a thermodynamic analysis and several parametric studies of this coupled system are presented for various configurations.

Design and reliability assessment of control systems for a nuclear-based hydrogen production plant with copper–chlorine thermochemical cycle

The thermochemical Copper–Chlorine (Cu–Cl) cycle is an emerging new method of nuclear-based hydrogen production. In the process, water is decomposed into hydrogen and oxygen through several physical and chemical processes. In this paper, a Distributed Control System (DCS) is designed for the thermochemical Cu–Cl cycle. The architecture and the communication networks of the DCS are discussed. Reliability of the DCS is assessed using fault trees. In the assessment, the impact of the malfunction of the actuators, sensors, controllers and communication networks on the overall system reliability is investigated. This provides key information for the selection of control system components, and determination of their inspection frequency and maintenance strategy. The hydrogen reactor unit, which is one of the major components in the thermochemical Cu–Cl cycle, is used to demonstrate the detailed design and analysis.

Efficiency analysis of a hybrid copper–chlorine (Cu–Cl) cycle for nuclear-based hydrogen production

The role of the Cu–Cl cycle for thermochemical water decomposition, potentially driven by heat from a nuclear power generation station, in producing hydrogen in a sustainable way is investigated by examining efficiencies. The energy efficiency of the cycle is found to be 45% and the exergy efficiency 10%. The energy and exergy efficiencies of the cycle are observed to vary with temperatures of the reactions and reference-environment, and cycle heat losses. A parametric study is carried out considering several heat losses, reaction and reference-environment temperatures, and component-efficiency scenarios.

Recent Canadian advances in nuclear-based hydrogen production and the thermochemical Cu–Cl cycle

This paper presents recent Canadian advances in nuclear-based production of hydrogen by electrolysis and the thermochemical copper-chlorine (Cu-Cl) cycle. This includes individual process and reactor developments within the Cu-Cl cycle, thermochemical properties, advanced materials, controls, safety, reliability, economic analysis of electrolysis at off-peak hours, and integrating hydrogen plants with Canada's nuclear power plants. These enabling technologies are being developed by a Canadian consortium, as part of the Generation IV International Forum (GIF) for hydrogen production from the next generation of nuclear reactors.

Fluid-particle mass transport of cupric chloride hydrolysis in a fluidized bed

This paper examines the mass transport phenomena of a hydrolysis reaction involving cupric chloride particles and superheated steam in a fluidized bed, as a part of the copper–chlorine thermochemical cycle for nuclear-based hydrogen production. The Gómez-Barea method was extended and utilized for the purpose of this study. A uniform reaction model (Volumetric Model; VM) and Shrinking Core Model (SCM) were used for limiting cases of the conversion processes. Using the solution procedures developed for each case, the effects of different parameters (such as the superficial gas velocity, bed inventory, and process temperature) were investigated in terms of the conversion of CuCl 2 particles and steam.