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75: CO 2 emissions during hydrogen production from different energy sources. 

75: CO 2 emissions during hydrogen production from different energy sources. 

Citations

... Standard parameters for power generation using gas turbine combined cycle with CO 2 capture are used [28]. Steady state operating conditions are assumed [29] appropriate to the current The components involved in the synthesis of the synthetic fuels involve chemical reactions which make it obligatory to consider both chemical and physical exergies. The physical exergy is denoted by ex ph and can be evaluated using the temperature and enthalpies and entropies of the reference and corresponding states using the following equation: ...
Article
This proposed study compares CO2‑based alternative fuel systems employing methanol, dimethyl ether and methane in the context of CO2 capture, utilization and storage (CCUS) efforts. Chemical fuels offer an approach to store and transport renewable electricity over long spatial and time scales. Longer-term carbon capture and storage (CCS) system development can benefit from near-term carbon-based fuel production employing captured CO2 as a precursor along with electrolytic hydrogen. Surplus renewable electricity (RE) or RE co-located with CCS developments can provide synthetic fuels to enable long-duration storage and long-distance RE transport. This study evaluates energy and exergy efficiencies when storing intermittent RE in the form of chemical fuels. The exergy analysis highlights the improvement potential in fuel synthesis, fuel combustion and other subsystems. The performance of the proposed carbon–neutral synthetic fuel systems are measured using H2-to-fuel (chemical conversion efficiency), H2-to-power and fuel-to-power efficiency metrics. Aspen Plus V11 is employed for the process simulation and Aspen Process Economic Analyzer V11 is used to compare the combustion economics. The results show that the methanol, DME and methane fuel systems provide H2-to-fuel energy efficiencies of 88.4%, 85.2% and 83.3% and exergic efficiencies of 92.9%, 92.1% and 86.2% respectively; H2-to-power energy efficiencies are 30.8%, 27.3% and 51.9% and exergy efficiencies are 30.5%, 27.1% and 51.7% respectively. These results highlight the relative merits of CCUS fuel pathways and potential for future efficiency improvements. The methane fuel pathway offers comparatively lower costs as compared with dimethyl ether and methanol routes. Furthermore, the detailed modeling efforts, efficiency results and sensitivity analyses conducted to investigate the performance of carbon–neutral synthetic fuel systems are presented and discussed.
... The gasification process is presented to be a sequence of a thermochemical transformations taking place at high temperatures between the organic part such as coal and the gasifying agent, like oxygen, steam, air, carbon dioxide [234] [235] [236]. The heat needed for the gasification process has been made by using the carbonaceous material (so it is called autothermic gasification) [234]. ...
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Abstract Hydrogen energy became the most significant energy as the current demand gradually starts to increase. Hydrogen energy is an important key solution to tackle the global temperature rise. The key important factor of hydrogen production is the hydrogen economy. Hydrogen production technologies are commercially available, while some of these technologies are still under development. This paper reviews the hydrogen production technologies from both fossil and non-fossil fuels such as (steam reforming, partial oxidation, auto thermal, pyrolysis, and plasma technology). Additionally, water electrolysis technology was reviewed. Water electrolysis can be combined with the renewable energy to get eco-friendly technology. Currently, the maximum hydrogen fuel productions were registered from the steam reforming, gasification, and partial oxidation technologies using fossil fuels. These technologies have different challenges such as the total energy consumption and carbon emissions to the environment are still too high. A novel non-fossil fuel method [ammonia NH3] for hydrogen production using plasma technology was reviewed. Ammonia decomposition using plasma technology without and with a catalyst to produce pure hydrogen was considered as compared case studies. It was showed that the efficiency of ammonia decomposition using the catalyst was higher than ammonia decomposition without the catalyst. The maximum hydrogen energy efficiency obtained from the developed ammonia decomposition system was 28.3% with a hydrogen purity of 99.99%. The development of ammonia decomposition processes is continues for hydrogen production, and it will likely become commercial and be used as a pure hydrogen energy source. Keywords Hydrogen Technology, Hydrogen Production, Steam Reforming, Plasma, Ammonia Decomposition
... Aspen Plus simulations of the CueCl cycle have been performed at the ANL [1] and UOIT [2] (see Figs. 1 and 2). Aspen Plus predicts the behavior of process reactions and steps using standard engineering relationships, mass and energy balances, as well as phase and chemical equilibrium data. ...
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This second of two companion papers presents the latest advances of an international team on the thermochemical copper–chlorine (Cu–Cl) cycle of hydrogen production. It specifically focuses on simulations, thermochemical data, advanced materials, safety, reliability and economics of the Cu–Cl cycle. Aspen Plus simulations of various system configurations are performed to improve the cycle efficiency. In addition, simulations based on exergo-economic and exergy-cost-energy-mass (EXCEM) methods for system design are presented. Modeling of the linkage between nuclear and hydrogen plants demonstrates how the Cu–Cl cycle would be integrated with an SCWR (Super Critical Water Reactor; Canada’s Generation IV reactor). Chemical potentials, solubilities, formation of Cu(I) and Cu(II) complexes and properties of Cu2OCl2, Cu(I) and Cu(II) chloride species are reported. In addition, the development of new advanced materials with improved corrosion resistance is presented. In particular, the performance of new anode electrode structures and thermal spray coatings is presented. This companion set of two papers presents new advances in a range of key enabling technologies for the thermochemical copper–chlorine cycle.
Article
As a carbon-free molecule, ammonia has gained great global interest in being considered a significant future candidate for the transition toward renewable energy. Numerous applications of ammonia as a fuel have been developed for energy generation, heavy transportation, and clean, distributed energy storage. There is a clear global target to achieve a sustainable economy and carbon neutrality. Therefore, most of the research's efforts are concentrated on generating cost-effective renewable energy on a large scale rather than fossil fuels. However, storage and transportation are still roadblocks for these technologies, for example, hydrogen technologies. Ammonia could be replaced as a viable fuel for a clean and sustainable future of global energy. More efforts from governments and scientists can lead to making ammonia a clean energy vector in most energy applications. In this review, ammonia synthesis was assessed, including conventional Haber–Bosch technology. Current hydrogen technologies as the key parameters for ammonia generation are also evaluated. The role of ammonia as a hydrogen-based fuel and generation roadmap are discussed for future utilization of energy mix. Further, ammonia generation processes are addressed in depth, including blue and green ammonia generation. A survey of ammonia synthesis catalytic materials was conducted and the role of catalyst materials in ammonia generation was compared, which showed that the Ru-based catalyst generated the maximum ammonia after 20 h of starting experiment. An end-use plan for using ammonia as a clean energy fuel in vehicles, marines, gas turbines as well as fuel cells, is briefly discussed to recognize the potential applications of ammonia use. The practical and future end-use vision of energy sources is proposed to achieve great benefits at low carbon emissions and costs. This review can provide prospective knowledge of large-scale aspects and environmental considerations of ammonia. Herein, we conclude that ammonia will become the “clean energy carrier link” that will achieve the global energy and economy sustainability targets.
Article
The aim of the study was to evaluate the efficiency of an energy-and-technology unit based on a continuous furnace of a rolling mill with an option for hydrogen production. A brief analysis of hydrogen production technologies and the prospects of their application in metallurgy are presented. It has been determined that as for enterprises with the potential of thermal waste, the use of thermochemical technologies is promising for the production of hydrogen. The main aspects and features of thermochemical methods of hydrogen production are shown from the standpoint of choosing the number of stages of chemical reactions implementation and determining the thermodynamic conditions for their conduct. The conditions for the implementation of the copper-chlorine Cu–Cl thermochemical cycle were investigated, and a rational variant of its implementation has been determined, taking into account the use of thermal waste (secondary energy resources) of the heating furnaces of the rolling mill. The application of the evolutionary method made it possible, on the basis of the technological scheme (which had been previously developed and investigated, and consisted of an energy-and-technological installation as a part of a rolling mill of a heating furnace and a utilization gas turbine with external heat supply that maintains the regenerative component of heating the air oxidizer), to synthesize a scheme of an energy-and-technological installation with the inclusion of a technological unit implementing a hybrid thermochemical copper-chlorine Cu–Cl cycle for separating water into hydrogen and oxygen using thermal secondary energy resources and electricity generated by a utilization gas turbine installation. Mathematical model of the macro level has been developed. The conducted numerical test experiments have shown the high energy prospects of the developed energy-and-technology installation, the fuel utilization rate of which is in the range of 75–90 %. The coefficient of chemical regeneration of fuel energy for the test mode was 11.3 %. As a result of numerical research, the prospects of developments under consideration in terms of the development of hydrogen production technologies with the use of thermochemical cycles and the high-temperature thermal secondary resources have been proved.
Chapter
Process integration opportunities for the Cu–Cl cycle of hydrogen production with nuclear and renewable energy sources are investigated. The advantages and disadvantages of each system are studied, and the cost of hydrogen production is analyzed and compared for various cases. In order to evaluate the environmental performance of the integrated hydrogen production systems, an environmental impact assessment of the proposed systems with a focus on the amount of CO2 emission is conducted and compared.
Chapter
In this chapter the role of nuclear energy in hydrogen production at large scale is discussed. In the first part of the chapter various routes of hydrogen generation using nuclear energy are described. Five routes are identified for hydrogen generation by water splitting, among which four are based on thermal energy derived from nuclear reactor, while the fifth is based on the radiolytic effect (that is, disintegration of water molecule under the impact of nuclear radiation). The role of hydrogen as energy storage medium for load levelling of the regional electrical grid is extensively discussed. It is shown that hydrogen production when electricity demand is low, storage and its use in fuel cell for power generation when electricity demand is high, represents a very attractive method for effective generation of electricity in regional grids, which reduces the costs and decreases the environmental production when nuclear energy is the primary source. Large-scale hydrogen production is also essential for petrochemical operations and heavy (nonconventional) oil upgrading, or oil-sand extraction/processing procedures. Hydrogen option represents a potential solution for transportation sector where it can be used either directly (hydrogen is stored onboard of vehicles) or indirectly (hydrogen is converted in a synthetic fuel such as gasoline, diesel, methanol, or ammonia). All means of transportation can benefit from hydrogen as energy carrier; in this chapter the road, rail, and air transport are analyzed in detail.
Chapter
In this chapter, the hybrid copper–chlorine (Cu–Cl) cycle for hydrogen production is examined in detail. The historical perspective of this cycle development is presented in Sect. 6.1. A precursor of the cycle was proposed in 1974, which uses a non-electrochemical, non-thermochemical disproportionation of cuprous chloride; this process is based on complexation and chelating schemes that generate the desired products. Electrochemical hydrogen generation from hydrochloric acid and cuprous chloride electrolysis is one of the latest cycle developments for engineering scale-up. This process simplifies the separation steps and it has been proven by test-bench experiments. Two reactors were mainly studied for the hydrolysis reaction, which is a crucial cycle step: fluidized bed and spray reactor. Both are interesting schemes proposed for scaling up the cycle. At the University of Ontario Institute of Technology, a scaled up laboratory facility has been developed for each cycle step.
Article
The Aspen Plus process simulation package is used to evaluate the characteristics of the four-step Cu–Cl thermochemical water splitting cycle in terms of energy and exergy, to support the ultimate development of a pilot plant. Alternative designs for the heat exchanger network using Aspen Energy Analyzer are developed and studied for thermal management within the Cu–Cl cycle. The simulation results for the four-step Cu–Cl cycle illustrate that the steam-to-copper molar ratio can be reduced to 10 from an initial value of 16 by decreasing the pressure of the hydrolysis reactor. A thermodynamic model of the four-step Cu–Cl cycle is developed to determine its energy and exergy efficiencies. The energy and exergy efficiencies of the four-step Cu–Cl cycle are determined to be 55.4% and 66.0%, respectively.
Article
This paper presents recent advances by an international team which is developing the thermochemical copper–chlorine (Cu–Cl) cycle for hydrogen production. Development of the Cu–Cl cycle has been pursued by several countries within the framework of the Generation IV International Forum (GIF) for hydrogen production with the next generation of nuclear reactors. Due to its lower temperature requirements in comparison with other thermochemical cycles, the Cu–Cl cycle is particularly well matched with Canada's Generation IV reactor, SCWR (Super-Critical Water Reactor), as well as other heat sources such as solar energy or industrial waste heat. In this paper, recent developments of the Cu–Cl cycle are presented, specifically involving unit operation experiments, corrosion resistant materials and system integration.