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Ibrahim Dincer - One of the best experts on this subject based on the ideXlab platform.
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exergoeconomic analysis of Hydrogen Production using a standalone high temperature electrolyzer
International Journal of Hydrogen Energy, 2021Co-Authors: Abdullah A Alzahrani, Ibrahim DincerAbstract:Abstract The conventional Hydrogen Production methods, primarily steam methane reforming and coal gasification, produce massive amounts of greenhouse gas emissions which significantly cause impacts on the environment. An alternative Hydrogen Production method is high-temperature electrolysis using Solid Oxide Electrolyzer that combines both high conversion efficiency and saleable high purity Hydrogen Production. The produced Hydrogen can feed the various industrial processes at different scales in addition to offering an environmentally friendly storage option. The scope of this paper is to examine the economic feasibility of this technology through the utilization of the exergoeconomic concept, which traces the flow of exergy through the system and price both waste and products. Therefore, a standalone solid oxide electrolyzer of a 1MWe is considered for Hydrogen Production using renewably generated electricity. Having the detailed exergy analysis conducted in earlier studies, the focus of this article is on the costing of each exergy stream to determine the exergy cost and the potential changes outcomes as a result of the system operating or design parameters optimization. It is found that the cost of Hydrogen Production through the modular high-temperature electrolyzer varies between $3-$9/kg with an average of about $5.7/kg, respectively.
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energy and exergy analyses of Hydrogen Production by coal gasification
International Journal of Hydrogen Energy, 2017Co-Authors: S S Seyitoglu, Ibrahim DincerAbstract:Abstract In this study, we examine an integrated coal based gasification system developed for Hydrogen Production and power generation. The proposed plant consists of air separation unit, gasification unit, gas cooling and cleaning unit, pressure swing absorption (PSA) for Hydrogen Production, high temperature electrolyzer for Hydrogen Production, Brayton cycle, steam Rankine cycle and organic Rankine cycle (ORC) system for power generation. We investigate this system through energy and exergy analyses for Hydrogen Production. Six coal types, such as Beypazari, Tuncbilek, Can, Yatagan, Elbistan and Soma are considered in this study and energy and exergy efficiencies of these coals are compared to each other for assessment and evaluation. The Aspen Plus and Engineering Equation Solver (EES) software packages are used for system simulation and system analyses. The results show that the overall energy and exergy efficiencies of the entire system become 41% and 36.5%, respectively.
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review of photocatalytic water splitting methods for sustainable Hydrogen Production
International Journal of Energy Research, 2016Co-Authors: Canan Acar, Ibrahim Dincer, Greg F. NatererAbstract:Summary This paper examines photocatalytic Hydrogen Production as a clean energy solution to address challenges of climate change and environmental sustainability. Advantages and disadvantages of various Hydrogen Production methods, with a particular emphasis on photocatalytic Hydrogen Production, are discussed in this paper. Social, environmental and economic aspects are taken into account while assessing selected Production methods and types of photocatalysts. In the first part of this paper, various Hydrogen Production options are introduced and comparatively assessed. Then, solar-based Hydrogen Production options are examined in a more detailed manner along with a comparative performance assessment. Next, photocatalytic Hydrogen Production options are introduced, photocatalysis mechanisms and principles are discussed and the main groups of photocatalysts, namely titanium oxide, cadmium sulfide, zinc oxide/sulfide and other metal oxide-based photocatalyst groups, are introduced. After discussing recycling issues of photocatalysts, a comparative performance assessment is conducted based on Hydrogen Production processes (both per mass and surface area of photocatalysts), band gaps and quantum yields. The results show that among individual photocatalysts, on average, Au–CdS has the best performance when band gap, quantum yield and Hydrogen Production rates are considered. From this perspective, TiO2–ZnO has the poorest performance. Among the photocatalyst groups, cadmium sulfides have the best average performance, while other metal oxides show the poorest rankings, on average. Copyright © 2016 John Wiley & Sons, Ltd.
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Sustainable Hydrogen Production
Sustainable Hydrogen Production, 2016Co-Authors: Ibrahim Dincer, Calin ZamfirescuAbstract:Identifying and building a sustainable energy system are perhaps two of the most critical issues that today's society must address. Replacing our current energy carrier mix with a sustainable fuel is one of the key pieces in that system. Hydrogen as an energy carrier, primarily derived from water, can address issues of sustainability, environmental emissions, and energy security. Issues relating to Hydrogen Production pathways are addressed here. Future energy systems require money and energy to build. Given that the United States has a finite supply of both, hard decisions must be made about the path forward, and this path must be followed with a sustained and focused effort.
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impact assessment and efficiency evaluation of Hydrogen Production methods
International Journal of Energy Research, 2015Co-Authors: Canan Acar, Ibrahim DincerAbstract:Summary In this study, we investigate the economic, environmental and social impacts of various Hydrogen Production methods, based on fossil fuel and renewable energy resources with a special emphasis on hybrid photoelectrochemical systems perform comparative assessments of these methods for applications. The sources considered for Hydrogen Production in this study are water, fossil hydrocarbons, and biomass. Furthermore, the primary energy sources considered in this study are natural gas, coal, biomass, wind and solar. In order to address sustainability, the relationship between efficiency and environmental impact is also investigated. The results show that solar based Hydrogen Production options (photocatalysis, photoelectrolysis, and photoelectrochemical methods) provide near zero global warming potentials and air pollutants, while coal gasification has the highest ones. In regards to the exergy efficiencies, biomass gasification gives the highest exergy efficiency, while photoelectrochemical method ends up with the lowest one. Copyright © 2015 John Wiley & Sons, Ltd.
Jianlong Wang - One of the best experts on this subject based on the ideXlab platform.
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fermentative Hydrogen Production from macroalgae laminaria japonica pretreated by microwave irradiation
International Journal of Hydrogen Energy, 2019Co-Authors: Yanan Yin, Jianlong WangAbstract:Abstract Pretreatment is an essential procedure to enhance the biodegradability when algae biomass is used as substrate for fermentative Hydrogen Production, In this study the potential of microwave pretreatment for enhancing the Hydrogen Production from macroalgae biomass Laminaria japonica was investigated. Microwave pretreatment at different temperatures (100–180 °C, 30 min) was explored, algae biomass disruption increased with increasing temperature, while highest Hydrogen yield of 15.8 mL/g TSadded was obtained from 160 °C microwave treated algae biomass. Hydrogen Production can be indicated by the deHydrogenase activity. After the microwave treatment, Hydrogen Production process altered from butyrate-type to acetate-type fermentation. Maximum Hydrogen yield was enhanced by 1.9 fold compared with the control test. Indicating microwave treatment can be a good candidate in enhancing the Hydrogen Production from macroalgae biomass.
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Fermentative Hydrogen Production using various biomass-based materials as feedstock
Renewable and Sustainable Energy Reviews, 2018Co-Authors: Jianlong Wang, Yanan YinAbstract:Hydrogen can be produced through different methods. Various biomass can be used as low-cost substrate for fermentative Hydrogen Production, which significantly reduces the Hydrogen Production cost. Furthermore, bioHydrogen Production from biomass wastes can achieve dual benefits of clean energy generation and waste management since agricultural and municipal wastes can be disposed at the same time. However, the application of Hydrogen Production from biomass meets the bottlenecks of low Hydrogen Production rate and substrate degradation rate. In this paper, various biomass as feedstock, including waste activated sludge produced form wastewater treatment plant, algae, agricultural residuals and municipal wastes used for biological Hydrogen Production, was reviewed. Since the hydrolysis to smaller molecules is the rate-limiting step for biomass degradation, a pretreatment step can enhance both the Hydrogen Production efficiency and biomass degradation rate. Pretreatment process can destroy the crystal structure of macromolecular substances and reduce their polymerization degree. Therefore the trapped components can be released through cell wall lysis and delignification of lignocellulosic biomass to make higher proportion of readily fermentable substances accessible for microorganisms. Various pretreatment methods used for treating biomass as feedstock for Hydrogen Production were analyzed and compared. Physical treatment, chemical treatment, biological treatment and a combination of different treatments are usually used for the pretreatment of biomass. Physical treatment methods include mill, grind, ultra-sonication, heat, freeze and thaw, microwave and ionizing radiation; chemical treatment methods comprise acid and alkaline treatment, oxidation by oxidizing agent and addition of methanogenic inhibitors; biological treatment methods mainly consist of enzymatic treatment and bacterial hydrolysis. Pretreatment is a critical process for fermentative Hydrogen Production from biomass. Considerable efforts are needed from both technical and managing aspects to achieve a full-scale application of fermentative Hydrogen Production from biomass.
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isolation and characterization of a novel strain clostridium butyricum inet1 for fermentative Hydrogen Production
International Journal of Hydrogen Energy, 2017Co-Authors: Yanan Yin, Jianlong WangAbstract:Abstract A novel Hydrogen-producing strain was isolated from gamma irradiated digested sludge and identified as Clostridium butyricum INET1. The fermentative Hydrogen Production performance of the newly isolated C. butyricum INET1 was characterized. Various carbon sources, including glucose, xylose, sucrose, lactose, starch and glycerol were used as substrate for Hydrogen Production. The operational conditions, including temperature, initial pH, substrate concentration and inoculation proportion were evaluated for their effects on Hydrogen Production, and the optimal condition was determined to be 35 °C, initial pH 7.0, 10 g/L glucose and 10% inoculation ratio. Cumulative Hydrogen Production of 218 mL/100 mL and Hydrogen yield of 2.07 mol H 2 /mol hexose was obtained. The results showed that C. butyricum INET1 is capable of utilizing different substrates (glucose, xylose, sucrose, lactose, starch and glycerol) for efficient Hydrogen Production, which is a potential candidate for fermentative Hydrogen Production.
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kinetic models for fermentative Hydrogen Production a review
International Journal of Hydrogen Energy, 2009Co-Authors: Jianlong WangAbstract:Abstract The kinetic models were developed and applied for fermentative Hydrogen Production. They were used to describe the progress of a batch fermentative Hydrogen Production process, to investigate the effects of substrate concentration, inhibitor concentration, temperatures, pH, and dilution rates on the process of fermentative Hydrogen Production, and to establish the relationship among the substrate degradation rate, the Hydrogen-producing bacteria growth rate and the product formation rate. This review showed that the modified Gompertz model was widely used to describe the progress of a batch fermentative Hydrogen Production process, while the Monod model was widely used to describe the effects of substrate concentration on the rates of substrate degradation, Hydrogen-producing bacteria growth and Hydrogen Production. Arrhenius model was used a lot to describe the effects of temperature on fermentative Hydrogen Production, while modified Han–Levenspiel model was used to describe the effects of inhibitor concentration on fermentative Hydrogen Production. The Andrew model was used to describe the effects of H + concentration on the specific Hydrogen Production rate, while the Luedeking–Piret model and its modified form were widely used to describe the relationship between the Hydrogen-producing bacteria growth rate and the product formation rate. Finally, some suggestions for future work with these kinetic models were proposed.
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factors influencing fermentative Hydrogen Production a review
International Journal of Hydrogen Energy, 2009Co-Authors: Jianlong WangAbstract:This review summarized several main factors influencing fermentative Hydrogen Production. The reviewed factors included inoculum, substrate, reactor type, nitrogen, phosphate, metal ion, temperature and pH. In this review, the effect of each factor on fermentative Hydrogen Production and the advance in the research of the effect were briefly introduced and discussed, followed by some suggestions for the future work of fermentative Hydrogen Production. This review showed that there usually existed some disagreements on the optimal condition of a given factor for fermentative Hydrogen Production, thus more researches in this respect are recommended. Furthermore, most of the studies on fermentative Hydrogen Production were conducted in batch mode using glucose and sucrose as substrate, thus more studies on fermentative Hydrogen Production in continuous mode using organic wastes as substrate are recommended.
Anastasios Melis - One of the best experts on this subject based on the ideXlab platform.
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Photobiological Hydrogen Production: Recent advances and state of the art
Bioresource technology, 2011Co-Authors: Ela Eroglu, Anastasios MelisAbstract:Photobiological Hydrogen Production has advanced significantly in recent years, and on the way to becoming a mature technology. A variety of photosynthetic and non-photosynthetic microorganisms, including unicellular green algae, cyanobacteria, anoxygenic photosynthetic bacteria, obligate anaerobic, and nitrogen-fixing bacteria are endowed with genes and proteins for H2-Production. Enzymes, mechanisms, and the underlying biochemistry may vary among these systems; however, they are all promising catalysts in Hydrogen Production. Integration of Hydrogen Production among these organisms and enzymatic systems is a recent concept and a rather interesting development in the field, as it may minimize feedstock utilization and lower the associated costs, while improving yields of Hydrogen Production. Photobioreactor development and genetic manipulation of the Hydrogen-producing microorganisms is also outlined in this review, as these contribute to improvement in the yield of the respective processes.
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Hydrogen Production during stationary phase in purple photosynthetic bacteria
International Journal of Hydrogen Energy, 2008Co-Authors: Matthew R Melnicki, Lucia Bianchi, Roberto De Philippis, Anastasios MelisAbstract:Abstract The merit of a Hydrogen Production system was investigated, where cells in the stationary phase of growth were treated as live enzymes, continually catalyzing Hydrogen Production in the absence of growth. Batch cultures of the purple photosynthetic bacteria Rhodospirillum rubrum UR2 were grown photoheterotrophically with succinate as the electron donor. Hydrogen evolved during growth, via the enzyme nitrogenase, at a rate of 21 mL gas L−1 culture h−1, and continued to evolve at high rates for about 70 h after cells had ceased growth. Hydrogen Production stopped precisely when succinate was depleted from the medium. Upon replenishment of succinate to the cultures, Hydrogen Production resumed but cells did not grow further; however, the rate and yield of Hydrogen Production was lower with successive succinate additions than that measured during growth. These results suggest that Hydrogen Production is not strictly coupled to growth. Nevertheless, the results also establish the necessity for cell growth in order to maintain maximal Hydrogen Production rates. Supplementation of cultures with limited amounts of fresh growth medium, given in addition to the succinate replenishment, partially restored the Hydrogen Production rate and yield, along with a proportional increase in cell biomass. Results were confirmed in parallel experiments with Rhodopseudomonas palustris CGA009. A strategy is suggested for enhancing the biofuels to biomass Production ratio under conditions of continuous cultivation with minimal cell growth (about 10% of the control), allowing a greater proportion of the cellular metabolic activity to be directed toward H2-Production.
Marc A Rosen - One of the best experts on this subject based on the ideXlab platform.
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investigation of an integrated Hydrogen Production system based on nuclear and renewable energy sources a new approach for sustainable Hydrogen Production via copper chlorine thermochemical cycles
International Journal of Energy Research, 2012Co-Authors: Mehmet F Orhan, Ibrahim Dincer, Marc A RosenAbstract:SUMMARY Hydrogen Production via thermochemical water decomposition is a potential process for direct utilization of nuclear thermal energy to increase efficiency and thereby facilitate energy savings. Thermochemical water splitting with a copper–chlorine (Cu–Cl) cycle could be linked with nuclear and renewable energy sources to decompose water into its constituents, oxygen and Hydrogen, through intermediate Cu and Cl compounds. In this study, we analyze a coupling of nuclear and renewable energy sources for Hydrogen Production by the Cu–Cl thermochemical cycle. Nuclear and renewable energy sources are reviewed to determine the most appropriate option for the Cu–Cl cycle. An environmental impact assessment is conducted and compared with conventional methods using fossil fuels and other options. The CO2 emissions for Hydrogen Production are negligibly small from renewables, 38 kg/kg H2 from coal, 27 kg/kg H2 from oil, and 18 kg/kg H2 from natural gas. Cost assessment studies of Hydrogen Production are presented for this integrated system and suggest that the cost of Hydrogen Production will decrease to $2.8/kg. Copyright © 2011 John Wiley & Sons, Ltd.
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exergetic life cycle assessment of a Hydrogen Production process
International Journal of Hydrogen Energy, 2012Co-Authors: Ahmet Ozbilen, Ibrahim Dincer, Marc A RosenAbstract:Abstract 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.
Michael K H Leung - One of the best experts on this subject based on the ideXlab platform.
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a review on reforming bio ethanol for Hydrogen Production
International Journal of Hydrogen Energy, 2007Co-Authors: Dennis Y C Leung, Michael K H LeungAbstract:Abstract Bio-ethanol is a prosperous renewable energy carrier mainly produced from biomass fermentation. Reforming of bio-ethanol provides a promising method for Hydrogen Production from renewable resources. Besides operating conditions, the use of catalysts plays a crucial role in Hydrogen Production through ethanol reforming. Rh and Ni are so far the best and the most commonly used catalysts for ethanol steam reforming towards Hydrogen Production. The selection of proper support for catalyst and the methods of catalyst preparation significantly affect the activity of catalysts. In terms of Hydrogen Production and long-term stability, MgO, ZnO, CeO 2 , and La 2 O 3 are suitable supports for Rh and Ni due to their basic characteristics, which favor ethanol deHydrogenation but inhibit dehydration. As Rh and Ni are inactive for water gas shift reaction (WGSR), the development of bimetallic catalysts, alloy catalysts, and double-bed reactors is promising to enhance Hydrogen Production and long-term catalyst stability. Autothermal reforming of bio-ethanol has the advantages of lesser external heat input and long-term stability. Its overall efficiency needs to be further enhanced, as part of the ethanol feedstock is used to provide low-grade thermal energy. Development of millisecond-contact time reactor provides a low-cost and effective way to reform bio-ethanol and hydrocarbons for fuel upgrading. Despite its early R&D stage, bio-ethanol reforming for Hydrogen Production shows promises for its future fuel cell applications.
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an overview of Hydrogen Production from biomass
Fuel Processing Technology, 2006Co-Authors: Meng Ni, Dennis Y C Leung, Michael K H Leung, K SumathyAbstract:Abstract Hydrogen Production plays a very important role in the development of Hydrogen economy. One of the promising Hydrogen Production approaches is conversion from biomass, which is abundant, clean and renewable. Alternative thermochemical (pyrolysis and gasification) and biological (biophotolysis, water–gas shift reaction and fermentation) processes can be practically applied to produce Hydrogen. This paper gives an overview of these technologies for Hydrogen Production from biomass. The future development will also be addressed.
