Hydrogen production by several cyanobacteria

Energy Technology Data Exchange (ETDEWEB)

Kumar, Dhruv; Kumar, H.D. (Banaras Hindu Univ., Varanasi (India). Dept. of Botany)

1992-11-01

Twenty species belonging to eleven genera of nitrogen-fixing and non-nitrogen-fixing cyanobacteria were screened for production of hydrogen. Only one species each of Nostoc and Anabaena showed light-and nitrogenase-dependent aerobic hydrogen production. The highest rate of aerobic hydrogen production was recorded in Anabaena sp. strain CA. When incubated anaerobically under 99% Ar + 1% CO[sub 2], all the tested strains produced hydrogen. Nickel supplementation completely abolished hydrogen production both under aerobic and anaerobic conditions, except in Anabaena sp. strain CA, where only the rate of production was decreased. Species of Plectonema, Oscillatoria and Spirulina showed methyl viologen-dependent (hydrogenase-dependent) hydrogen production. Other physiological activities were also studied with a view to selecting a suitable organism for large-scale production of hydrogen. (author)

Hydrogen production by sodium borohydride in NaOH aqueous solution

Science.gov (United States)

Wang, Q.; Zhang, L. F.; Zhao, Z. G.

2018-01-01

The kinetics of hydrolysis reaction of NaBH4 in NaOH aqueous solution is studied. The influence of pH of the NaOH aqueous solution on the rate of hydrogen production and the hydrogen production efficiency are studied for the hydrolysis reaction of NaBH4. The results show that the activation energy of hydrolysis reaction of NaBH4 increased with the increase of the initial pH of NaOH aqueous solution.With the increasing of the initial pH of NaOH aqueous solution, the rate of hydrogen production and hydrogen production efficiency of NaBH4 hydrolysis decrease.

Lactulose mediates suppression of dextran sodium sulfate-induced colon inflammation by increasing hydrogen production.

Science.gov (United States)

Chen, Xiao; Zhai, Xiao; Shi, Jiazi; Liu, Wen Wu; Tao, Hengyi; Sun, Xuejun; Kang, Zhimin

2013-06-01

Molecular hydrogen (H2) is a potent antioxidant and able to protect organs from oxidative stress injuries. Orally administered lactulose, a potent H2 inducer, is digested by colon microflora and significantly increases H2 production, indicating its potential anti-inflammatory action. To evaluate the anti-inflammatory effects of lactulose on dextran sodium sulfate (DSS)-induced colitis in mice. Mice were randomly assigned into seven groups, receiving regular distilled water, H2-rich saline (peritoneal injection), DSS, oral lactulose (0.1, 0.15, 0.2 ml/10 g, respectively), and lactulose (0.2 ml/10 g) + oral antibiotics. The mouse model of human ulcerative colitis was established by supplying mice with water containing DSS. The H2 breath test was used to determine the exhaled H2 concentration. Body weight, colitis score, colon length, pathological features and tumor necrosis factor alpha (TNF-α), interleukin-1β (IL-1β), maleic dialdehyde (MDA) and marrow peroxidase (MPO) levels in colon lesions were evaluated. After 7 days, DSS-induced loss of body weight, increase of colitis score, shortening of colon length, pathological changes and elevated levels of TNF-α, IL-1β, MDA, and MPO in colon lesions, were significantly suppressed by oral lactulose administration and intraperitoneally injected H2-rich saline. Ingestion of antibiotics significantly compromised the anti-inflammatory effects of lactulose. The H2 breath test showed that lactulose administration significantly induced hydrogen production and that antibiotics administration could inhibit H2 production. Lactulose can prevent the development of DSS-induced colitis and alleviate oxidative stress in the colon, as measured by MDA and MPO, probably by increasing endogenous H2 production.

Enhanced thermophilic fermentative hydrogen production from cassava stillage by chemical pretreatments.

Science.gov (United States)

Wang, Wen; Luo, Gang; Xie, Li; Zhou, Qi

2013-01-01

Acid and alkaline pretreatments for enhanced hydrogen production from cassava stillage were investigated in the present study. The result showed that acid pretreatment was suitable for enhancement of soluble carbohydrate while alkaline pretreatment stimulated more soluble total organic carbon production from cassava stillage. Acid pretreatment thereby has higher capacity to promote hydrogen production compared with alkaline pretreatment. Effects of pretreatment temperature, time and acid concentration on hydrogen production were also revealed by response surface methodology. The results showed that the increase of all factors increased the soluble carbohydrate production, whereas hydrogen production was inhibited when the factors exceeded their optimal values. The optimal conditions for hydrogen production were pretreatment temperature 89.5 °C, concentration 1.4% and time 69 min for the highest hydrogen production of 434 mL, 67% higher than raw cassava stillage.

Hydrogen production by the hyperthermophilic bacterium Thermotoga maritima Part II: modeling and experimental approaches for hydrogen production.

Science.gov (United States)

Auria, Richard; Boileau, Céline; Davidson, Sylvain; Casalot, Laurence; Christen, Pierre; Liebgott, Pierre Pol; Combet-Blanc, Yannick

2016-01-01

Thermotoga maritima is a hyperthermophilic bacterium known to produce hydrogen from a large variety of substrates. The aim of the present study is to propose a mathematical model incorporating kinetics of growth, consumption of substrates, product formations, and inhibition by hydrogen in order to predict hydrogen production depending on defined culture conditions. Our mathematical model, incorporating data concerning growth, substrates, and products, was developed to predict hydrogen production from batch fermentations of the hyperthermophilic bacterium, T. maritima . It includes the inhibition by hydrogen and the liquid-to-gas mass transfer of H 2 , CO 2 , and H 2 S. Most kinetic parameters of the model were obtained from batch experiments without any fitting. The mathematical model is adequate for glucose, yeast extract, and thiosulfate concentrations ranging from 2.5 to 20 mmol/L, 0.2-0.5 g/L, or 0.01-0.06 mmol/L, respectively, corresponding to one of these compounds being the growth-limiting factor of T. maritima . When glucose, yeast extract, and thiosulfate concentrations are all higher than these ranges, the model overestimates all the variables. In the window of the model validity, predictions of the model show that the combination of both variables (increase in limiting factor concentration and in inlet gas stream) leads up to a twofold increase of the maximum H 2 -specific productivity with the lowest inhibition. A mathematical model predicting H 2 production in T. maritima was successfully designed and confirmed in this study. However, it shows the limit of validity of such mathematical models. Their limit of applicability must take into account the range of validity in which the parameters were established.

Enhanced thermophilic fermentative hydrogen production from cassava stillage by chemical pretreatments

DEFF Research Database (Denmark)

Wang, Wen; Luo, Gang; Xie, Li

2013-01-01

Acid and alkaline pretreatments for enhanced hydrogen production from cassava stillage were investigated in the present study. The result showed that acid pretreatment was suitable for enhancement of soluble carbohydrate while alkaline pretreatment stimulated more soluble total organic carbon...... that the increase of all factors increased the soluble carbohydrate production, whereas hydrogen production was inhibited when the factors exceeded their optimal values. The optimal conditions for hydrogen production were pretreatment temperature 89.5 °C, concentration 1.4% and time 69 min for the highest hydrogen...

Hydrogen production methods

International Nuclear Information System (INIS)

Hammerli, M.

1982-07-01

Old, present and new proceses for producing hydrogen are assessed critically. The emphasis throughout is placed on those processes which could be commercially viable before the turn of the century for large-scale hydrogen manufacture. Electrolysis of water is the only industrial process not dependent on fossil resources for large-scale hydrogen production and is likely to remain so for the next two or three decades. While many new processes, including those utilizing sunlight directly or indirectly, are presently not considered to be commercially viable for large-scale hydrogen production, research and development effort is needed to enhance our understanding of the nature of these processes. Water vapour electrolysis is compared with thermochemical processes: the former has the potential for displacing all other processes for producing hydrogen and oxygen from water

Hydrogen production from the monomeric sugars hydrolyzed from hemicellulose by Enterobacter aerogenes

Energy Technology Data Exchange (ETDEWEB)

Ren, Yunli; Wang, Jianji; Liu, Zhen; Ren, Yunlai; Li, Guozhi [School of Chemical Engineering and Pharmaceutics, Henan University of Science and Technology, Luoyang 471039, Henan (China)

2009-12-15

Relatively large percentages of xylose with glucose, arabinose, mannose, galactose and rhamnose constitute the hydrolysis products of hemicellulose. In this paper, hydrogen production performance of facultative anaerobe (Enterobacter aerogenes) has been investigated from these different monomeric sugars except glucose. It was shown that the stereoisomers of mannose and galactose were more effective for hydrogen production than those of xylose and arabinose. The substrate of 5 g/l xylose resulted in a relative high level of hydrogen yield (73.8 mmol/l), hydrogen production efficiency (2.2 mol/mol) and a maximum hydrogen production rate (249 ml/l/h). The hydrogen yield, hydrogen production efficiency and the maximum hydrogen production rate reached 104 mmol/l, 2.35 mol/mol and 290 ml/l/h, respectively, on a substrate of 10 g/l galactose. The hydrogen yields and the maximum hydrogen production rates increased with an increase of mannose concentrations and reached 119 mmol/l and 518 ml/l/h on the culture of 25 g/l mannose. However, rhamnose was a relative poor carbon resource for E. aerogenes to produce hydrogen, from which the hydrogen yield and hydrogen production efficiency were about one half of that from the mannose substrate. E. aerogenes was found to be a promising strain for hydrogen production from hydrolysis products of hemicellulose. (author)

Microalgal hydrogen production - A review.

Science.gov (United States)

Khetkorn, Wanthanee; Rastogi, Rajesh P; Incharoensakdi, Aran; Lindblad, Peter; Madamwar, Datta; Pandey, Ashok; Larroche, Christian

2017-11-01

Bio-hydrogen from microalgae including cyanobacteria has attracted commercial awareness due to its potential as an alternative, reliable and renewable energy source. Photosynthetic hydrogen production from microalgae can be interesting and promising options for clean energy. Advances in hydrogen-fuel-cell technology may attest an eco-friendly way of biofuel production, since, the use of H 2 to generate electricity releases only water as a by-product. Progress in genetic/metabolic engineering may significantly enhance the photobiological hydrogen production from microalgae. Manipulation of competing metabolic pathways by modulating the certain key enzymes such as hydrogenase and nitrogenase may enhance the evolution of H 2 from photoautotrophic cells. Moreover, biological H 2 production at low operating costs is requisite for economic viability. Several photobioreactors have been developed for large-scale biomass and hydrogen production. This review highlights the recent technological progress, enzymes involved and genetic as well as metabolic engineering approaches towards sustainable hydrogen production from microalgae. Copyright © 2017 Elsevier Ltd. All rights reserved.

Production of hydrogen from organic waste via hydrogen sulfide

International Nuclear Information System (INIS)

McMahon, M.; Davis, B.R.; Roy, A.; Daugulis, A.

2007-01-01

In this paper an integrated process is proposed that converts organic waste to hydrogen via hydrogen sulphide. The designed bioreactor has achieved high volumetric productivities comparable to methanogenic bioreactors. Proposed process has advantages of bio-methane production and is more resilient to process upset. Thermochemical conversion of hydrogen sulphide to hydrogen is exothermic and also requires smaller plant infrastructure

Electrocatalytic approach for the efficiency increase of electrolytic hydrogen production: Proof-of-concept using platinum-dysprosium alloys

International Nuclear Information System (INIS)

Santos, D.M.F.; Šljukić, B.; Sequeira, C.A.C.; Macciò, D.; Saccone, A.; Figueiredo, J.L.

2013-01-01

Development of electrocatalytic materials for the hydrogen evolution reaction (HER) is attempted with the aim of reducing the water electrolysis overpotential and increasing its efficiency. Using linear scan voltammetry measurements of the hydrogen discharge enables evaluation of the electrocatalytic activity for the HER of platinum–dysprosium (Pt–Dy) intermetallic alloy electrodes of different compositions. Understanding of materials electrocatalytic performance is based on determination of several crucial kinetic parameters, including the Tafel coefficients, b, charge transfer coefficients, α, exchange current densities, j 0 , and activation energies, E a . Influence of temperature on HER is investigated by performing studies at temperatures ranging from 25 °C to 85 °C. The effect of the Dy amount in the efficiency of the HER on the Pt–Dy alloys is analysed. Results demonstrate that Dy can substantially increase the electrocatalytic activity of the Pt alloys, in comparison to the single Pt electrode. Efforts are made to correlate the microstructure of the alloys with their performance towards the HER. - Highlights: ► Development of electrocatalysts to increase efficiency of electrolytic hydrogen production. ► Synthesis and evaluation of composition and morphology of platinum–dysprosium (Pt–Dy) alloys. ► Hydrogen evolution reaction on Pt–Dy alloys electrodes studied using linear scan voltammetry in alkaline medium. ► Pt–Dy alloy with equiatomic composition enhances kinetics of hydrogen discharge compared to single Pt

Development of hydrogen production technology using FBR

International Nuclear Information System (INIS)

Ono, Kiyoshi; Otaki, Akira; Chikazawa, Yoshitaka; Nakagiri, Toshio; Sato, Hiroyuki; Sekine, Takashi; Ooka, Makoto

2004-06-01

This report describes the features of technology, the schedule and the organization for the research and development regarding the hydrogen production technology using FBR thermal energy. Now, the hydrogen production system is proposed as one of new business models for FBR deployment. This system is the production of hydrogen either thermal energy at approximately from 500degC to 550degC or electricity produced by a sodium cooled FBR. Hydrogen is expected to be one of the future clean secondary energies without carbon-dioxide emission. Meanwhile the global energy demand will increase, especially in Asian countries, and the energy supply by fossil fuels is not the best choice considering the green house effect and the stability of energy supply. The development of the hydrogen technology using FBR that satisfies 'sustainable energy development' and 'utilization of energies free from environmental pollution' will be one of the promising options. Based on the above mentioned recognition, we propose the direction of the development, the issues to be solved, the time schedule, the budget, and the organization for R and D of three hydrogen production technologies, the thermochemical hybrid process, the low temperature steam reforming process, and the high temperature steam electrolysis process in JNC. (author)

Hydrogen from algal biomass: A review of production process

Directory of Open Access Journals (Sweden)

Archita Sharma

2017-09-01

Full Text Available Multifariousness of biofuel sources has marked an edge to an imperative energy issue. Production of hydrogen from microalgae has been gathering much contemplation right away. But, mercantile production of microalgae biofuels considering bio-hydrogen is still not practicable because of low biomass concentration and costly down streaming processes. This review has taken up the hydrogen production by microalgae. Biofuels are the up and coming alternative to exhaustible, environmentally and unsafe fossil fuels. Algal biomass has been considered as an enticing raw material for biofuel production, these days photobioreactors and open-air systems are being used for hydrogen production from algal biomass. The formers allow the careful cultivation control whereas the latter ones are cheaper and simpler. A contemporary, encouraging optimization access has been included called algal cell immobilization on various matrixes which has resulted in marked increase in the productivity per volume of a reactor and addition of the hydrogen-production phase.

Hydrogen production by alkaline water electrolysis

Directory of Open Access Journals (Sweden)

Diogo M. F. Santos

2013-01-01

Full Text Available Water electrolysis is one of the simplest methods used for hydrogen production. It has the advantage of being able to produce hydrogen using only renewable energy. To expand the use of water electrolysis, it is mandatory to reduce energy consumption, cost, and maintenance of current electrolyzers, and, on the other hand, to increase their efficiency, durability, and safety. In this study, modern technologies for hydrogen production by water electrolysis have been investigated. In this article, the electrochemical fundamentals of alkaline water electrolysis are explained and the main process constraints (e.g., electrical, reaction, and transport are analyzed. The historical background of water electrolysis is described, different technologies are compared, and main research needs for the development of water electrolysis technologies are discussed.

Hydrogen Production Costs of Various Primary Energy Sources

International Nuclear Information System (INIS)

Choi, Jae Hyuk; Tak, Nam Il; Kim, Yong Hee; Park, Won Seok

2005-11-01

Many studies on the economical aspects of hydrogen energy technologies have been conducted with the increase of the technical and socioeconomic importance of the hydrogen energy. However, there is still no research which evaluates the economy of hydrogen production from the primary energy sources in consideration of Korean situations. In this study, the hydrogen production costs of major primary energy sources are compared in consideration of the Korean situations such as feedstock price, electricity rate, and load factor. The evaluation methodology is based on the report of the National Academy of Science (NAS) of U.S. The present study focuses on the possible future technology scenario defined by NAS. The scenario assumes technological improvement that may be achieved if present research and development (R and D) programs are successful. The production costs by the coal and natural gas are 1.1 $/kgH 2 and 1.36 $/kgH 2 , respectively. However, the fossil fuels are susceptible to the price variation depending on the oil and the raw material prices, and the hydrogen production cost also depends on the carbon tax. The economic competitiveness of the renewable energy sources such as the wind, solar, and biomass are relatively low when compared with that of the other energy sources. The estimated hydrogen production costs from the renewable energy sources range from 2.35 $/kgH 2 to 6.03 $/kgH 2 . On the other hand, the production cost by nuclear energy is lower than that of natural gas or coal when the prices of the oil and soft coal are above $50/barrel and 138 $/ton, respectively. Taking into consideration the recent rapid increase of the oil and soft coal prices and the limited fossil resource, the nuclear-hydrogen option appears to be the most economical way in the future

Biological hydrogen production

Energy Technology Data Exchange (ETDEWEB)

Benemann, J.R. [Univ. of California, Berkeley, CA (United States)

1995-11-01

Biological hydrogen production can be accomplished by either thermochemical (gasification) conversion of woody biomass and agricultural residues or by microbiological processes that yield hydrogen gas from organic wastes or water. Biomass gasification is a well established technology; however, the synthesis gas produced, a mixture of CO and H{sub 2}, requires a shift reaction to convert the CO to H{sub 2}. Microbiological processes can carry out this reaction more efficiently than conventional catalysts, and may be more appropriate for the relatively small-scale of biomass gasification processes. Development of a microbial shift reaction may be a near-term practical application of microbial hydrogen production.

Hydrogen production by aqueous phase catalytic reforming of glycerine

International Nuclear Information System (INIS)

Ozguer, Derya Oncel; Uysal, Bekir Zuehtue

2011-01-01

Hydrogen is believed to be the one of the main energy carriers in the near future. In this research glycerine, which is produced in large quantities as a by-product of biodiesel process, was converted to hydrogen aiming to contribute to clean energy initiative. Conversion of glycerol to hydrogen was achieved via aqueous-phase reforming (APR) with Pt/Al 2 O 3 catalyst. The experiments were carried out in an autoclave reactor and a continuous fixed-bed reactor. The effects of reaction temperature (160-280 o C), feed flow rate (0.05-0.5 mL/dak) and feed concentration (5-85 wt-% glycerine) on product distribution were investigated. Optimum temperature for hydrogen production with APR was determined as 230 o C. Maximum gas production rate was found at the feed flow rates around 0.1 mL/min. It was also found that hydrogen concentration in the gas product increased with decreasing glycerol concentration in the feed.

Extremophile mediated hydrogen production for hydrogenation of substrates in aqueous media

Science.gov (United States)

Anjom, Mouzhgun

Catalytic hydrogenation reactions are pervasive throughout our economy, from production of margarine as food, liquid fuels for transportation and chiral drugs such as L-DOPA. H2 production from non-fossil fuel feedstocks is highly desirable for transition to the "Hydrogen Economy". Also, the rates of hydrogenation reactions that involve a substrate, H 2 gas and a catalyst are often limited by the solubility of H2 in solvent. The present research thus envisioned designing water-soluble catalysts that could effectively utilize biologically produced H2 in a coupled system to hydrogenate substrates in homogeneous mode (two-phase system). Biological production of H2 as an end product or byproduct of the metabolism of organisms that operate under strict anaerobic conditions has been proposed. However, contrary to what was previously observed, Thermotoga neapolitana, belonging to the order of Thermotogales efficiently produces H2 gas under microaerobic conditions (Van Ooteghem et al. 2004). For H2 production by T. neapolitana in the bacterial growth medium (DSM 5068) at an optimum temperature of 70 C, our results in batch mode show that: (1) H2 was produced from glucose though with 16% efficiency, the rest goes to biomass production, (2) H2 gas was produced even when the cultures were inoculated under microaerobic conditions (up to 8% (v/v) O2) suggesting a protective mechanism for one or more [Fe-Fe] hydrogenases in T. neapolitana, (3) H2 production was pH dependent but addition of simple, non-toxic physiological buffering additives such as Methylene succinic acid increased H2 production and (4) H2 production rate varied linearly in the 100--6800 kPa pressure range. We then screened various water-soluble metal catalysts in batch mode and selected the RhCl3.3H2O/TPPTS (TPPTS is a water-soluble ligand) system that achieved 86% hydrogenation of Methylene succinic acid (an olefin) in an aqueous medium pressurized with preformed H2. When water was replaced with the DSM 5068

Photoelectrochemical hydrogen production

Energy Technology Data Exchange (ETDEWEB)

Rocheleau, R.E.; Miller, E.; Misra, A. [Univ. of Hawaii, Honolulu, HI (United States)

1996-10-01

The large-scale production of hydrogen utilizing energy provided by a renewable source to split water is one of the most ambitious long-term goals of the U.S. Department of Energy`s Hydrogen Program. One promising option to meet this goal is direct photoelectrolysis in which light absorbed by semiconductor-based photoelectrodes produces electrical power internally to split water into hydrogen and oxygen. Under this program, direct solar-to-chemical conversion efficiencies as high as 7.8 % have been demonstrated using low-cost, amorphous-silicon-based photoelectrodes. Detailed loss analysis models indicate that solar-to-chemical conversion greater than 10% can be achieved with amorphous-silicon-based structures optimized for hydrogen production. In this report, the authors describe the continuing progress in the development of thin-film catalytic/protective coatings, results of outdoor testing, and efforts to develop high efficiency, stable prototype systems.

Study on commercial HTGR hydrogen production system

International Nuclear Information System (INIS)

Nishihara, Tetsuo

2000-07-01

The Japanese energy demand in 2030 will increase up to 117% in comparison with one in 2000. We have to avoid a large consumption of fossil fuel that induces a large CO 2 emission from viewpoint of global warming. Furthermore new energy resources expected to resolve global warming have difficulty to be introduced more because of their low energy density. As a result, nuclear power still has a possibility of large introduction to meet the increasing energy demand. On the other hand, in Japan, 40% of fossil fuels in the primary energy are utilized for power generation, and the remaining are utilized as a heat source. New clean energy is required to reduce the consumption of fossil fuels and hydrogen is expected as a alternative energy resource. Prediction of potential hydrogen demand in Japan is carried out and it is clarified that the demand will potentially increase up to 4% of total primary energy in 2050. In present, steam reforming method is the most economical among hydrogen generation processes and the cost of hydrogen production is about 7 to 8 yen/m 3 in Europe and the United States and about 13 yen/m 3 in Japan. JAERI has proposed for using the HTGR whose maximum core outlet temperature is at 950degC as a heat source in the steam reforming to reduced the consumption of fossil fuels and resulting CO 2 emission. Based on the survey of the production rate and the required thermal energy in conventional industry, it is clarified that a hydrogen production system by the steam reforming is the best process for the commercial HTGR nuclear heat utilization. The HTGR steam reforming system and other candidate nuclear heat utilization systems are considered from viewpoint of system layout and economy. From the results, the hydrogen production cost in the HTGR stream reforming system is expected to be about 13.5 yen/m 3 if the cost of nuclear heat of the HTGR is the same as one of the LWR. (author)

Hydrogen peroxide production is not primarily increased in human myotubes established from type 2 diabetic subjects.

Science.gov (United States)

Minet, A D; Gaster, M

2011-09-01

Increased oxidative stress and mitochondrial dysfunction have been implicated in the development of insulin resistance in type 2 diabetes. To date, it is unknown whether increased mitochondrial reactive oxygen species (ROS) production in skeletal muscle from patients with type 2 diabetes is primarily increased or a secondary adaptation to environmental, lifestyle, and hormonal factors. This study investigates whether ROS production is primarily increased in isolated diabetic myotubes. Mitochondrial membrane potential, hydrogen peroxide (H(2)O(2)), superoxide, and mitochondrial mass were determined in human myotubes precultured under normophysiological conditions. Furthermore, the corresponding ATP synthesis was measured in isolated mitochondria. Muscle biopsies were taken from 10 lean subjects, 10 obese subjects, and 10 subjects with type 2 diabetes; satellite cells were isolated, cultured, and differentiated to myotubes. Mitochondrial mass, membrane potential/mitochondrial mass, and superoxide-production/mitochondrial mass were not different between groups. In contrast, H(2)O(2) production/mitochondrial mass and ATP production were significantly reduced in diabetic myotubes compared to lean controls (P production is not primarily increased in diabetic myotubes but rather is reduced. Moreover, the comparable ATP/H(2)O(2) ratios indicate that the reduced ROS production in diabetic myotubes parallels the reduced ATP production because ROS production in diabetic myotubes must be considered to be in a proportion comparable to lean. Thus, the increased ROS production seen in skeletal muscle of type 2 diabetic patients is an adaptation to the in vivo conditions.

Status of the Korean nuclear hydrogen production project

International Nuclear Information System (INIS)

Jonghwa, Chang; Won-Jae, Lee

2010-01-01

The rapid climate changes and the heavy reliance on imported fuel in Korea have motivated interest in the hydrogen economy. The Korean government has set up a long-term vision for transition to the hydrogen economy. To meet the expected demand of hydrogen as a fuel, hydrogen production using nuclear energy was also discussed. Recently the Korean Atomic Energy Committee has approved nuclear hydrogen production development and demonstration which will lead to commercialisation in late 2030's. An extensive research and development programme for the production of hydrogen using nuclear power has been underway since 2004 in Korea. During the first three years, a technological area was identified for the economic and efficient production of hydrogen using a VHTR. A pre-conceptual design of the commercial nuclear hydrogen production plant was also performed. As a result, the key technology area in the core design, the hydrogen production process, the coupling between reactor and chemical side, and the coated fuel were identified. During last three years, research activities have been focused on the key technology areas. A nuclear hydrogen production demonstration plant (NHDD) consisting of a 200 MWth capacity VHTR and five trains of water-splitting plants was proposed for demonstration of the performance and the economics of nuclear hydrogen. The computer tools for the VHTR and the water-splitting process were created and validated to some extent. The TRISO-coated particle fuel was fabricated and qualified. The properties of high temperature materials, including nuclear graphite, were studied. The sulphur-iodine thermochemical process was proved on a 3 litre/ hour scale. A small gas loop with practical pressure and temperature with the secondary sulphur acid loop was successfully built and commissioned. The results of the first phase research increased the confidence in the nuclear hydrogen technology. From 2009, the government decided to support further key technology

Achievements of European projects on membrane reactor for hydrogen production

NARCIS (Netherlands)

di Marcoberardino, G.; Binotti, M.; Manzolini, G.; Viviente, J.L.; Arratibel Plazaola, A.; Roses, L.; Gallucci, F.

2017-01-01

Membrane reactors for hydrogen production can increase both the hydrogen production efficiency at small scale and the electric efficiency in micro-cogeneration systems when coupled with Polymeric Electrolyte Membrane fuel cells. This paper discusses the achievements of three European projects

Technical Analysis of Hydrogen Production

Energy Technology Data Exchange (ETDEWEB)

Ali T-Raissi

2005-01-14

The aim of this work was to assess issues of cost, and performance associated with the production and storage of hydrogen via following three feedstocks: sub-quality natural gas (SQNG), ammonia (NH{sub 3}), and water. Three technology areas were considered: (1) Hydrogen production utilizing SQNG resources, (2) Hydrogen storage in ammonia and amine-borane complexes for fuel cell applications, and (3) Hydrogen from solar thermochemical cycles for splitting water. This report summarizes our findings with the following objectives: Technoeconomic analysis of the feasibility of the technology areas 1-3; Evaluation of the hydrogen production cost by technology areas 1; and Feasibility of ammonia and/or amine-borane complexes (technology areas 2) as a means of hydrogen storage on-board fuel cell powered vehicles. For each technology area, we reviewed the open literature with respect to the following criteria: process efficiency, cost, safety, and ease of implementation and impact of the latest materials innovations, if any. We employed various process analysis platforms including FactSage chemical equilibrium software and Aspen Technologies AspenPlus and HYSYS chemical process simulation programs for determining the performance of the prospective hydrogen production processes.

Hydrogen Production from Optimal Wind-PV Energies Systems

Energy Technology Data Exchange (ETDEWEB)

Tafticht, T.; Agbossou, K. [Institut de recherche sur l hydrogene, Universite du Quebec - Trois-Rivieres, C.P. 500, Trois-Rivieres, (Ciheam), G9A 5H7, (Canada)

2006-07-01

Electrolytic hydrogen offers a promising alternative for long-term energy storage of renewable energies (RE). A stand-alone RE system based on hydrogen production has been developed at the Hydrogen Research Institute and successfully tested for automatic operation with designed control devices. The system is composed of a wind turbine, a photovoltaic (PV) array, an electrolyser, batteries for buffer energy storage, hydrogen and oxygen storage tanks, a fuel cell, AC and DC loads, power conditioning devices and different sensors. The long-term excess energy with respect to load demand has been sent to the electrolyser for hydrogen production and then the fuel cell has utilised this stored hydrogen to produce electricity when there were insufficient wind and solar energies with respect to load requirements. The RE system components have substantially different voltage-current characteristics and they are integrated on the DC bus through power conditioning devices for optimal operation by using the developed Maximum Power Point Tracking (MPPT) control method. The experimental results show that the power gain obtained by this method clearly increases the hydrogen production and storage rate from wind-PV systems. (authors)

Hydrogen Production from Optimal Wind-PV Energies Systems

International Nuclear Information System (INIS)

T Tafticht; K Agbossou

2006-01-01

Electrolytic hydrogen offers a promising alternative for long-term energy storage of renewable energies (RE). A stand-alone RE system based on hydrogen production has been developed at the Hydrogen Research Institute and successfully tested for automatic operation with designed control devices. The system is composed of a wind turbine, a photovoltaic (PV) array, an electrolyzer, batteries for buffer energy storage, hydrogen and oxygen storage tanks, a fuel cell, AC and DC loads, power conditioning devices and different sensors. The long-term excess energy with respect to load demand has been sent to the electrolyser for hydrogen production and then the fuel cell has utilised this stored hydrogen to produce electricity when there were insufficient wind and solar energies with respect to load requirements. The RE system components have substantially different voltage-current characteristics and they are integrated on the DC bus through power conditioning devices for optimal operation by using the developed Maximum Power Point Tracking (MPPT) control method. The experimental results show that the power gain obtained by this method clearly increases the hydrogen production and storage rate from wind-PV systems. (authors)

Hydrogen Production from Optimal Wind-PV Energies Systems

International Nuclear Information System (INIS)

Tafticht, T.; Agbossou, K.

2006-01-01

Electrolytic hydrogen offers a promising alternative for long-term energy storage of renewable energies (RE). A stand-alone RE system based on hydrogen production has been developed at the Hydrogen Research Institute and successfully tested for automatic operation with designed control devices. The system is composed of a wind turbine, a photovoltaic (PV) array, an electrolyser, batteries for buffer energy storage, hydrogen and oxygen storage tanks, a fuel cell, AC and DC loads, power conditioning devices and different sensors. The long-term excess energy with respect to load demand has been sent to the electrolyser for hydrogen production and then the fuel cell has utilised this stored hydrogen to produce electricity when there were insufficient wind and solar energies with respect to load requirements. The RE system components have substantially different voltage-current characteristics and they are integrated on the DC bus through power conditioning devices for optimal operation by using the developed Maximum Power Point Tracking (MPPT) control method. The experimental results show that the power gain obtained by this method clearly increases the hydrogen production and storage rate from wind-PV systems. (authors)

Hydrogen Production from Optimal Wind-PV Energies Systems

Energy Technology Data Exchange (ETDEWEB)

T Tafticht; K Agbossou [Institut de recherche sur l hydrogene, Universite du Quebec - Trois-Rivieres, C.P. 500, Trois-Rivieres, (Ciheam), G9A 5H7, (Canada)

2006-07-01

Electrolytic hydrogen offers a promising alternative for long-term energy storage of renewable energies (RE). A stand-alone RE system based on hydrogen production has been developed at the Hydrogen Research Institute and successfully tested for automatic operation with designed control devices. The system is composed of a wind turbine, a photovoltaic (PV) array, an electrolyzer, batteries for buffer energy storage, hydrogen and oxygen storage tanks, a fuel cell, AC and DC loads, power conditioning devices and different sensors. The long-term excess energy with respect to load demand has been sent to the electrolyser for hydrogen production and then the fuel cell has utilised this stored hydrogen to produce electricity when there were insufficient wind and solar energies with respect to load requirements. The RE system components have substantially different voltage-current characteristics and they are integrated on the DC bus through power conditioning devices for optimal operation by using the developed Maximum Power Point Tracking (MPPT) control method. The experimental results show that the power gain obtained by this method clearly increases the hydrogen production and storage rate from wind-PV systems. (authors)

Effects of solution volume on hydrogen production by pulsed spark discharge in ethanol solution

Energy Technology Data Exchange (ETDEWEB)

Xin, Y. B.; Sun, B., E-mail: sunb88@dlmu.edu.cn; Zhu, X. M.; Yan, Z. Y.; Liu, H.; Liu, Y. J. [College of Environmental Science and Engineering, Dalian Maritime University, Dalian 116026 (China)

2016-07-15

Hydrogen production from ethanol solution (ethanol/water) by pulsed spark discharge was optimized by varying the volume of ethanol solution (liquid volume). Hydrogen yield was initially increased and then decreased with the increase in solution volume, which achieved 1.5 l/min with a solution volume of 500 ml. The characteristics of pulsed spark discharge were studied in this work; the results showed that the intensity of peak current, the rate of current rise, and energy efficiency of hydrogen production can be changed by varying the volume of ethanol solution. Meanwhile, the mechanism analysis of hydrogen production was accomplished by monitoring the process of hydrogen production and the state of free radicals. The analysis showed that decreasing the retention time of gas production and properly increasing the volume of ethanol solution can enhance the hydrogen yield. Through this research, a high-yield and large-scale method of hydrogen production can be achieved, which is more suitable for industrial application.

Zero emission distributed hydrogen production

International Nuclear Information System (INIS)

Maddaloni, J.; Rowe, A.; Bailey, R.; McDonald, J.D.

2004-01-01

demonstration hydrogen production and fueling station near Victoria, BC. The station would demonstrate the viability of the proposed process to generate hydrogen while increasing the performance of the natural gas distribution system. The station could provide the ability to fuel vehicles as part of the Victoria node of the hydrogen highway project to be implemented for the 2010 Winter Olympic games. (author)

Hydrogen production from sewage sludge by steam gasification

Energy Technology Data Exchange (ETDEWEB)

Aye, L.; Klinkajorn, P. [Melbourne Univ. International Technologies Centre, Melbourne, Victoria (Australia). Dept. of Civil and Environmental Engineering

2006-07-01

Because of the shortage of energy sources in the near future, renewable energy, such as biomass, has become an important source of energy. One of the most common approaches for producing gaseous fuels from biomass is gasification. The main product gases of gasification are hydrogen, carbon monoxide, methane and low molecular weight hydrocarbons. Because of the capability of very low emission at the point of use, the interest in using hydrogen for electrical power generation and in electric-vehicles has been increasing. Hydrogen from biomass steam gasification (SG) is a net zero green house gas emission fuel. Sewage sludge (SS) has a potential to produce hydrogen-rich gaseous fuel. Therefore, hydrogen production from sewage sludge may be a solution for cleaner fuel and the sewage sludge disposal problem. This paper presented the results of a computer model for SSSG by using Gibbs free energy minimization (GFEM) method. The computer model developed was used to determine the hydrogen production limits for various steam to biomass ratios. The paper presented an introduction to renewable energy and gasification and discussed the Gibbs free energy minimization method. The study used a RAND algorithm. It presented the computer model input parameters and discussed the results of the stoichiometric analysis and Gibbs free energy minimization. The energy requirement for hydrogen production was also presented. 17 refs., 1 tab., 6 figs.

Production of hydrogen from hydrocarbons

Energy Technology Data Exchange (ETDEWEB)

Lohmueller, R

1984-03-01

Hydrocarbons are the preferred starting materials for the industrial production of hydrogen. Most hydrogen is produced by steam reforming of light hydrocarbons. Partial oxidation of heavy oil and residue is used for the production of H/sub 2/ and synthesis gas in large plants. In both cases gas purification was improved. Hydrogen-rich gases like coke oven gas, refinery-offgas, and offgases from the chemical and petrochemical industry have high potential for becoming a major source of hydrogen. Processes for recovering H/sub 2/ (and by-products) are condensation and rectification at low temperatures and, most attractive and versatile for the production of very pure H/sub 2/, adsorption (PSA). The environmental impact of H/sub 2/ production lies mainly in the emission of CO/sub 2/ and heat. Other forms of pollution can be considerably reduced by conventional methods. The economy of H/sub 2/ production depends essentially on price and availability of the raw materials.

Exploring optimal conditions for thermophilic fermentative hydrogen production from cassava stillage

Energy Technology Data Exchange (ETDEWEB)

Luo, Gang; Zou, Zhonghai; Wang, Wen [Key Laboratory of Yangtze River Water Environment, Ministry(Tongji University), Siping Road no 1239, Shanghai 200092 (China); Xie, Li; Zhou, Qi [Key Laboratory of Yangtze River Water Environment, Ministry(Tongji University), Siping Road no 1239, Shanghai 200092 (China); UNEP-Tongji University Institute of Environment for Sustainable Development, Siping Road no 1239, Shanghai 200092 (China)

2010-06-15

This study investigated the effects of seed sludges, alkalinity and HRT on the thermophilic fermentative hydrogen production from cassava stillage. Five different kinds of sludges were used as inocula without any pretreatment. Though batch experiments showed that mesophilic anaerobic sludge was the best inoculum, the hydrogen yields with different seed sludges were quite similar in continuous experiments in the range of 82.9-92.3 ml H{sub 2}/gVS without significant differences which could be attributed to the establishment of Uncultured Thermoanaerobacteriaceae bacterium-dominant microbial communities in all reactors. It is indicated that results obtained from batch experiments are not consistent with those from continuous experiments and all the tested seed sludges are good sources for continuous thermophilic hydrogen production from cassava stillage. The influent alkalinity of 6 g NaHCO{sub 3}/L and HRT 24 h were optimal for hydrogen production with hydrogen yield of 76 ml H{sub 2}/gVS and hydrogen production rate of 3215 ml H{sub 2}/L/d. Butyrate was the predominant metabolite in all experiments. With the increase in alkalinity of more than 6 g/L, the concentration of VFA/ethanol increased while hydrogen yield decreased due to the higher concentration of acetate and propionate. The decrease in HRT resulted in the higher hydrogen production rate but lower hydrogen yield. Variation of hydrogen yields were quite correlated with butyrate/acetate (B/A) ratio with different influent alkalinities, however, butyrate was important parameter to justify the hydrogen yields with various HRTs. (author)

Hydrogen production from biomass by thermochemical recuperative energy conversion

Energy Technology Data Exchange (ETDEWEB)

Fushimi, C.; Araki, K.; Yamaguchi, Y.; Tsutsumi, A. [Tokyo Univ. (Japan). Dept. of Chemical System Engineering

2002-07-01

The authors conducted, using a thermogravimetric reactor, a kinetic study of production of thermochemical recuperative hydrogen from biomass. The four different biomass materials used were: cellulose, lignin, metroxylon stem, and coconut husk. Under both rapid heating and slow heating conditions, the weight changes of the biomass samples during the steam gasification or pyrolysis were measured at 973 Kelvin. Simultaneously, measurements of the evolution rates of low-molecular-weight gas products such as hydrogen, methane, carbon monoxide, and carbon dioxide were taken with the help of a mass spectrometer and a micro gas chromatograph (GC). The steam gasification of char significantly increased the amount of hydrogen and carbon dioxide production. The results also indicated that at higher heating rate, the cold gas efficiency of steam gasification was increased. This can be explained by the suppression of the tar production at lower temperature. 25 refs., 2 tabs., 10 figs.

Hydrogen production using plasma processing

International Nuclear Information System (INIS)

Wagner, D.; Whidden, T.K.

2006-01-01

Plasma processing is a promising method of extracting hydrogen from natural gas while avoiding the greenhouse gas (GHG) production typical of other methods such as steam methane reforming. This presentation describes a plasma discharge process based that, in a single reactor pass, can yield hydrogen concentrations of up to 50 % by volume in the product gas mixture. The process is free of GHG's, does not require catalysts and is easily scalable. Chemical and morphological analyses of the gaseous and solid products of the process by gas-chromatography/mass-spectrometry, microscopic Raman analyses and electron microscopy respectively are reviewed. The direct production of hydrogen-enriched natural gas (HENG) as a fuel for low pollution internal combustion engines and its purification to high-purity hydrogen (99.99%) from the product gas by pressure swing adsorption (PSA) purifier beds are reviewed. The presentation reviews potential commercial applications for the technology

Hydrogen sulfide increases nitric oxide production from endothelial cells by an Akt-dependent mechanism

Directory of Open Access Journals (Sweden)

Arturo J Cardounel

2011-12-01

Full Text Available Hydrogen sulfide (H2S and nitric oxide (NO are both gasotransmitters that can elicit synergistic vasodilatory responses in the in the cardiovascular system, but the mechanisms behind this synergy are unclear. In the current study we investigated the molecular mechanisms through which H2S regulates endothelial NO production. Initial studies were performed to establish the temporal and dose-dependent effects of H2S on NO generation using EPR spin trapping techniques. H2S stimulated a two-fold increase in NO production from endothelial nitric oxide synthase (eNOS, which was maximal 30 min after exposure to 25-150 µM H2S. Following 30 min H2S exposure, eNOS phosphorylation at Ser 1177 was significantly increased compared to control, consistent with eNOS activation. Pharmacological inhibition of Akt, the kinase responsible for Ser 1177 phosphorylation, attenuated the stimulatory effect of H2S on NO production. Taken together, these data demonstrate that H2S up-regulates NO production from eNOS through an Akt-dependent mechanism. These results implicate H2S in the regulation of NO in endothelial cells, and suggest that deficiencies in H2S signaling can directly impact processes regulated by NO.

Photobiological hydrogen production

Energy Technology Data Exchange (ETDEWEB)

Seibert, M; Lien, S; Weaver, P F

1979-01-01

Hydrogen production by phototrophic organisms, which has been known since the 1930's, occurs at the expense of light energy and electron-donating substrates. Three classes of organisms, namely, photosynthetic bacteria, cyanobacteria, and algae carry out this function. The primary hydrogen-producing enzyme systems, hydrogenase and nitrogenase, will be discussed along with the manner in which they couple to light-driven electron transport. In addition, the feasibility of using in vivo and in vitro photobiological hydrogen producing systems in future solar energy conversion applications will be examined.

Fusion Energy for Hydrogen Production

Energy Technology Data Exchange (ETDEWEB)

Fillo, J. A.; Powell, J. R.; Steinberg, M.; Salzano, F.; Benenati, R.; Dang, V.; Fogelson, S.; Isaacs, H.; Kouts, H.; Kushner, M.; Lazareth, O.; Majeski, S.; Makowitz, H.; Sheehan, T. V.

1978-09-01

The decreasing availability of fossil fuels emphasizes the need to develop systems which will produce synthetic fuel to substitute for and supplement the natural supply. An important first step in the synthesis of liquid and gaseous fuels is the production of hydrogen. Thermonuclear fusion offers an inexhaustible source of energy for the production of hydrogen from water. Depending on design, electric generation efficiencies of approximately 40 to 60% and hydrogen production efficiencies by high temperature electrolysis of approximately 50 to 70% are projected for fusion reactors using high temperature blankets.

Hydrogen production with a solar steam–methanol reformer and colloid nanocatalyst

KAUST Repository

Lee, Ming-Tsang; Werhahn, Michael; Hwang, David J.; Hotz, Nico; Greif, Ralph; Poulikakos, Dimos; Grigoropoulos, Costas P.

2010-01-01

of the reformer and thereby increase hydrogen production. The hydrogen production output efficiency is determined and a value of 5% is achieved. Experiments using concentrated solar simulator light as the radiation source are also carried out. The results show

New efficient hydrogen process production from organosilane hydrogen carriers derivatives

Energy Technology Data Exchange (ETDEWEB)

Brunel, Jean Michel [Unite URMITE, UMR 6236 CNRS, Faculte de Medecine et de Pharmacie, Universite de la Mediterranee, 27 boulevard Jean Moulin, 13385 Marseille 05 (France)

2010-04-15

While the source of hydrogen constitutes a significant scientific challenge, addressing issues of hydrogen storage, transport, and delivery is equally important. None of the current hydrogen storage options, liquefied or high pressure H{sub 2} gas, metal hydrides, etc.. satisfy criteria of size, costs, kinetics, and safety for use in transportation. In this context, we have discovered a methodology for the production of hydrogen on demand, in high yield, under kinetic control, from organosilane hydrogen carriers derivatives and methanol as co-reagent under mild conditions catalyzed by a cheap ammonium fluoride salt. Finally, the silicon by-products can be efficiently recycle leading to an environmentally friendly source of energy. (author)

Liquid hydrogen production via hydrogen sulfide methane reformation

Science.gov (United States)

Huang, Cunping; T-Raissi, Ali

Hydrogen sulfide (H 2S) methane (CH 4) reformation (H 2SMR) (2H 2S + CH 4 = CS 2 + 4H 2) is a potentially viable process for the removal of H 2S from sour natural gas resources or other methane containing gases. Unlike steam methane reformation that generates carbon dioxide as a by-product, H 2SMR produces carbon disulfide (CS 2), a liquid under ambient temperature and pressure-a commodity chemical that is also a feedstock for the synthesis of sulfuric acid. Pinch point analyses for H 2SMR were conducted to determine the reaction conditions necessary for no carbon lay down to occur. Calculations showed that to prevent solid carbon formation, low inlet CH 4 to H 2S ratios are needed. In this paper, we analyze H 2SMR with either a cryogenic process or a membrane separation operation for production of either liquid or gaseous hydrogen. Of the three H 2SMR hydrogen production flowsheets analyzed, direct liquid hydrogen generation has higher first and second law efficiencies of exceeding 80% and 50%, respectively.

Photobiological hydrogen production

Energy Technology Data Exchange (ETDEWEB)

Seibert, M.; Lien, S.; Weaver, P.F.

1979-01-01

Hydrogen production by phototrophic organisms, which has been known since the 1930's, occurs at the expense of light energy and electron-donating substrates. Three classes of organisms, namely, photosynthetic bacteria, cyanobacteria, and algae carry out this function. The primary hydrogen-producing enzyme systems, hydrogenase and nitrogenase, will be discussed along with the manner in which they couple to light-driven electron transport. In addition, the feasibility of using in vivo and in vitro photobiological hydrogen producing systems in future solar energy conversion applications will be examined.

Biological hydrogen production from biomass by thermophilic bacteria

International Nuclear Information System (INIS)

Claassen, P.A.M.; Mars, A.E.; Budde, M.A.W.; Lai, M.; de Vrije, T.; van Niel, E.W.J.

2006-01-01

To meet the reduction of the emission of CO 2 imposed by the Kyoto protocol, hydrogen should be produced from renewable primary energy. Besides the indirect production of hydrogen by electrolysis using electricity from renewable resources, such as sunlight, wind and hydropower, hydrogen can be directly produced from biomass. At present, there are two strategies for the production of hydrogen from biomass: the thermochemical technology, such as gasification, and the biotechnological approach using micro-organisms. Biological hydrogen production delivers clean hydrogen with an environmental-friendly technology and is very suitable for the conversion of wet biomass in small-scale applications, thus having a high chance of becoming an economically feasible technology. Many micro-organisms are able to produce hydrogen from mono- and disaccharides, starch and (hemi)cellulose under anaerobic conditions. The anaerobic production of hydrogen is a common phenomenon, occurring during the process of anaerobic digestion. Here, hydrogen producing micro-organisms are in syn-trophy with methanogenic bacteria which consume the hydrogen as soon as it is produced. In this way, hydrogen production remains obscure and methane is the end-product. By uncoupling hydrogen production from methane production, hydrogen becomes available for recovery and exploitation. This study describes the use of extreme thermophilic bacteria, selected because of a higher hydrogen production efficiency as compared to mesophilic bacteria, for the production of hydrogen from renewable resources. As feedstock energy crops like Miscanthus and Sorghum bicolor and waste streams like domestic organic waste, paper sludge and potato steam peels were used. The feedstock was pretreated and/or enzymatically hydrolyzed prior to fermentation to make a fermentable substrate. Hydrogen production by Caldicellulosiruptor saccharolyticus, Thermotoga elfii and T. neapolitana on all substrates was observed. Nutrient

Hydrogen and methane production from household solid waste in the two-stage fermentation process

DEFF Research Database (Denmark)

Lui, D.; Liu, D.; Zeng, Raymond Jianxiong

2006-01-01

A two-stage process combined hydrogen and methane production from household solid waste was demonstrated working successfully. The yield of 43 mL H-2/g volatile solid (VS) added was generated in the first hydrogen production stage and the methane production in the second stage was 500 mL CH4/g VS...... added. This figure was 21% higher than the methane yield from the one-stage process, which was run as control. Sparging of the hydrogen reactor with methane gas resulted in doubling of the hydrogen production. PH was observed as a key factor affecting fermentation pathway in hydrogen production stage....... Furthermore, this study also provided direct evidence in the dynamic fermentation process that, hydrogen production increase was reflected by acetate to butyrate ratio increase in liquid phase. (c) 2006 Elsevier Ltd. All rights reserved....

Deletion of Proton Gradient Regulation 5 (PGR5) and PGR5-Like 1 (PGRL1) proteins promote sustainable light-driven hydrogen production in Chlamydomonas reinhardtii due to increased PSII activity under sulfur deprivation.

Science.gov (United States)

Steinbeck, Janina; Nikolova, Denitsa; Weingarten, Robert; Johnson, Xenie; Richaud, Pierre; Peltier, Gilles; Hermann, Marita; Magneschi, Leonardo; Hippler, Michael

2015-01-01

Continuous hydrogen photo-production under sulfur deprivation was studied in the Chlamydomonas reinhardtii pgr5 pgrl1 double mutant and respective single mutants. Under medium light conditions, the pgr5 exhibited the highest performance and produced about eight times more hydrogen than the wild type, making pgr5 one of the most efficient hydrogen producer reported so far. The pgr5 pgrl1 double mutant showed an increased hydrogen burst at the beginning of sulfur deprivation under high light conditions, but in this case the overall amount of hydrogen produced by pgr5 pgrl1 as well as pgr5 was diminished due to photo-inhibition and increased degradation of PSI. In contrast, the pgrl1 was effective in hydrogen production in both high and low light. Blocking photosynthetic electron transfer by DCMU stopped hydrogen production almost completely in the mutant strains, indicating that the main pathway of electrons toward enhanced hydrogen production is via linear electron transport. Indeed, PSII remained more active and stable in the pgr mutant strains as compared to the wild type. Since transition to anaerobiosis was faster and could be maintained due to an increased oxygen consumption capacity, this likely preserves PSII from photo-oxidative damage in the pgr mutants. Hence, we conclude that increased hydrogen production under sulfur deprivation in the pgr5 and pgrl1 mutants is caused by an increased stability of PSII permitting sustainable light-driven hydrogen production in Chlamydomonas reinhardtii.

Hydrogen production from small hyropower sites. Final report

Energy Technology Data Exchange (ETDEWEB)

1980-04-01

A synergistic relationship was not found to exist between low-head hydropower and electrolytic hydrogen production. The storageability of hydrogen was expected to mitigate problems of hydrogen generation variability associated with the use of low-head hydropower as the power source. The expense of gaseous hydrogen storage equipment effectively eliminates storage as a means to decouple hydrogen demand and power/hydrogen production. From the opposite perspective, the availability of a low and stable cost of power from low-head hydro was expected to improve the competitiveness of electrolysis. In actuality, the results indicated that hydroelectric power from small dams would be comparatively expensive by current grid power standards (mid-1979). Electrolysis, in the capacity range considered here, is less sensitive to the cost of the power than originally presumed. Other costs including depreciation and capital related charges are more significant. Due to power generation variability, sole reliance on low-head hydropower to provide electricity to the cells would reduce the utilization of the hydrogen production investment, resulting in an increase in unit production costs. These factors were paramount in the Air Products recommendation to discontinue the study before continuing to more detailed stages of analysis, including an analysis of a site specific facility and the construction of a demonstration facility. Another major factor was the unavailability of a pipeline hydrogen supply situation which, because of lower distribution and capital costs, could have been commercially viable. An unfavorable judgment on the combined facility should not be misinterpreted and extended to the component systems. Although a detailed analysis of the individual prospects for electrolysis and low-head hydropower was beyond the study scope, the reader will realize, as the study is reviewed, that each is worthy of individual consideration.

Hydrogen production processes; Procedes de production d'hydrogene

Energy Technology Data Exchange (ETDEWEB)

NONE

2003-07-01

The goals of this first Gedepeon workshop on hydrogen production processes are: to stimulate the information exchange about research programs and research advances in the domain of hydrogen production processes, to indicate the domains of interest of these processes and the potentialities linked with the coupling of a nuclear reactor, to establish the actions of common interest for the CEA, the CNRS, and eventually EDF, that can be funded in the framework of the Gedepeon research group. This document gathers the slides of the 17 presentations given at this workshop and dealing with: the H{sub 2} question and the international research programs (Lucchese P.); the CEA's research program (Lucchese P., Anzieu P.); processes based on the iodine/sulfur cycle: efficiency of a facility - flow-sheets, efficiencies, hard points (Borgard J.M.), R and D about the I/S cycle: Bunsen reaction (Colette S.), R and D about the I/S cycle: the HI/I{sub 2}/H{sub 2}O system (Doizi D.), demonstration loop/chemical engineering (Duhamet J.), materials and corrosion (Terlain A.); other processes under study: the Westinghouse cycle (Eysseric C.), other processes under study at the CEA (UT3, plasma,...) (Lemort F.), database about thermochemical cycles (Abanades S.), Zn/ZnO cycle (Broust F.), H{sub 2} production by cracking, high temperature reforming with carbon trapping (Flamant G.), membrane technology (De Lamare J.); high-temperature electrolysis: SOFC used as electrolyzers (Grastien R.); generic aspects linked with hydrogen production: technical-economical evaluation of processes (Werkoff F.), thermodynamic tools (Neveu P.), the reactor-process coupling (Aujollet P.). (J.S.)

Hydrogen Storage and Production Project

Energy Technology Data Exchange (ETDEWEB)

Bhattacharyya, Abhijit [Univ. of Arkansas, Little Rock, AR (United States); Biris, A. S. [Univ. of Arkansas, Little Rock, AR (United States); Mazumder, M. K. [Univ. of Arkansas, Little Rock, AR (United States); Karabacak, T. [Univ. of Arkansas, Little Rock, AR (United States); Kannarpady, Ganesh [Univ. of Arkansas, Little Rock, AR (United States); Sharma, R. [Univ. of Arkansas, Little Rock, AR (United States)

2011-07-31

This is the final technical report. This report is a summary of the project. The goal of our project is to improve solar-to-hydrogen generation efficiency of the PhotoElectroChemical (PEC) conversion process by developing photoanodes with high absorption efficiency in the visible region of the solar radiation spectrum and to increase photo-corrosion resistance of the electrode for generating hydrogen from water. To meet this goal, we synthesized nanostructured heterogeneous semiconducting photoanodes with a higher light absorption efficiency compared to that of TiO₂ and used a corrosion protective layer of TiO₂. While the advantages of photoelectrochemical (PEC) production of hydrogen have not yet been realized, the recent developments show emergence of new nanostructural designs of photoanodes and choices of materials with significant gains in photoconversion efficiency.

HTTR workshop (workshop on hydrogen production technology)

International Nuclear Information System (INIS)

Shiina, Yasuaki; Takizuka, Takakazu

2004-12-01

Various research and development efforts have been performed to solve the global energy and environmental problems caused by large consumption of fossil fuels. Research activities on advanced hydrogen production technology by the use of nuclear heat from high temperature gas cooled reactors, for example, have been flourished in universities, research institutes and companies in many countries. The Department of HTTR Project and the Department of Advanced Nuclear Heat Technology of JAERI held the HTTR Workshop (Workshop on Hydrogen Production Technology) on July 5 and 6, 2004 to grasp the present status of R and D about the technology of HTGR and the nuclear hydrogen production in the world and to discuss about necessity of the nuclear hydrogen production and technical problems for the future development of the technology. More than 110 participants attended the Workshop including foreign participants from USA, France, Korea, Germany, Canada and United Kingdom. In the Workshop, the presentations were made on such topics as R and D programs for nuclear energy and hydrogen production technologies by thermo-chemical or other processes. Also, the possibility of the nuclear hydrogen production in the future society was discussed. The workshop showed that the R and D for the hydrogen production by the thermo-chemical process has been performed in many countries. The workshop affirmed that nuclear hydrogen production could be one of the competitive supplier of hydrogen in the future. The second HTTR Workshop will be held in the autumn next year. (author)

Nuclear hydrogen production and its safe handling

International Nuclear Information System (INIS)

Chung, Hongsuk; Paek, Seungwoo; Kim, Kwang-Rag; Ahn, Do-Hee; Lee, Minsoo; Chang, Jong Hwa

2003-01-01

An overview of the hydrogen related research presently undertaken at the Korea Atomic Energy Research Institute are presented. These encompass nuclear hydrogen production, hydrogen storage, and the safe handling of hydrogen, High temperature gas-cooled reactors can play a significant role, with respect to large-scale hydrogen production, if used as the provider of high temperature heat in fossil fuel conversion or thermochemical cycles. A variety of potential hydrogen production methods for high temperature gas-cooled reactors were analyzed. They are steam reforming of natural gas, thermochemical cycles, etc. The produced hydrogen should be stored safely. Titanium metal was tested primarily because its hydride has very low dissociation pressures at normal storage temperatures and a high capacity for hydrogen, it is easy to prepare and is non-reactive with air in the expected storage conditions. There could be a number of potential sources of hydrogen evolution risk in a nuclear hydrogen production facility. In order to reduce the deflagration detonation it is necessary to develop hydrogen control methods that are capable of dealing with the hydrogen release rate. A series of experiments were conducted to assess the catalytic recombination characteristics of hydrogen in an air stream using palladium catalysts. (author)

Rubisco mutants of Chlamydomonas reinhardtii enhance photosynthetic hydrogen production.

Science.gov (United States)

Pinto, T S; Malcata, F X; Arrabaça, J D; Silva, J M; Spreitzer, R J; Esquível, M G

2013-06-01

Molecular hydrogen (H2) is an ideal fuel characterized by high enthalpy change and lack of greenhouse effects. This biofuel can be released by microalgae via reduction of protons to molecular hydrogen catalyzed by hydrogenases. The main competitor for the reducing power required by the hydrogenases is the Calvin cycle, and rubisco plays a key role therein. Engineered Chlamydomonas with reduced rubisco levels, activity and stability was used as the basis of this research effort aimed at increasing hydrogen production. Biochemical monitoring in such metabolically engineered mutant cells proceeded in Tris/acetate/phosphate culture medium with S-depletion or repletion, both under hypoxia. Photosynthetic activity, maximum photochemical efficiency, chlorophyll and protein levels were all measured. In addition, expression of rubisco, hydrogenase, D1 and Lhcb were investigated, and H2 was quantified. At the beginning of the experiments, rubisco increased followed by intense degradation. Lhcb proteins exhibited monomeric isoforms during the first 24 to 48 h, and D1 displayed sensitivity under S-depletion. Rubisco mutants exhibited a significant decrease in O2 evolution compared with the control. Although the S-depleted medium was much more suitable than its complete counterpart for H2 production, hydrogen release was observed also in sealed S-repleted cultures of rubisco mutated cells under low-moderate light conditions. In particular, the rubisco mutant Y67A accounted for 10-15-fold higher hydrogen production than the wild type under the same conditions and also displayed divergent metabolic parameters. These results indicate that rubisco is a promising target for improving hydrogen production rates in engineered microalgae.

Liquid hydrogen production via hydrogen sulfide methane reformation

Energy Technology Data Exchange (ETDEWEB)

Huang, Cunping; T-Raissi, Ali [University of Central Florida, Florida Solar Energy Center, 1769 Clearlake Road, Cocoa, FL 32922 (United States)

2008-01-03

Hydrogen sulfide (H{sub 2}S) methane (CH{sub 4}) reformation (H{sub 2}SMR) (2H{sub 2}S + CH{sub 4} = CS{sub 2} + 4H{sub 2}) is a potentially viable process for the removal of H{sub 2}S from sour natural gas resources or other methane containing gases. Unlike steam methane reformation that generates carbon dioxide as a by-product, H{sub 2}SMR produces carbon disulfide (CS{sub 2}), a liquid under ambient temperature and pressure - a commodity chemical that is also a feedstock for the synthesis of sulfuric acid. Pinch point analyses for H{sub 2}SMR were conducted to determine the reaction conditions necessary for no carbon lay down to occur. Calculations showed that to prevent solid carbon formation, low inlet CH{sub 4} to H{sub 2}S ratios are needed. In this paper, we analyze H{sub 2}SMR with either a cryogenic process or a membrane separation operation for production of either liquid or gaseous hydrogen. Of the three H{sub 2}SMR hydrogen production flowsheets analyzed, direct liquid hydrogen generation has higher first and second law efficiencies of exceeding 80% and 50%, respectively. (author)

Photochemical hydrogen production system

International Nuclear Information System (INIS)

Copeland, R.J.

1990-01-01

Both technical and economic factors affect the cost of producing hydrogen by photochemical processes. Technical factors include the efficiency and the capital and operating costs of the renewable hydrogen conversion system; economic factors include discount rates, economic life, credit for co-product oxygen, and the value of the energy produced. This paper presents technical and economic data for a system that generates on-peak electric power form photochemically produced hydrogen

Economical analysis of biofuel products and nuclear plant hydrogen

International Nuclear Information System (INIS)

Edwaren Liun

2011-01-01

The increasing in oil prices over the last six years is unprecedented that should be seen as a spur to increased efficiency. The surge in oil prices on the world market today is driven by strong demand factors in the depletion of world oil reserves. To replace the fuel oil from the bowels of the earth the various alternatives should be considered, including other crops or vegetable oil production of bio-fuels and hydrogen are produced by high temperature nuclear reactors. Biofuels in the form of ethanol made from corn or sugar cane and biodiesel made from palm oil or jatropha. With the latest world oil prices, future fuel vegetable oil and nuclear hydrogen-based energy technologies become popular in various parts of the world. Economics of biodiesel will be changed in accordance with world oil prices and subsidy regulations which apply to fuel products. On the other hand the role of nuclear energy in hydrogen production with the most potential in the techno-economics is a form of high temperature steam electrolysis, using heat and electricity from nuclear reactors. The production cost of biodiesel fuel on the basis of ADO type subsidy is 10.49 US$/MMBTU, while the production cost of hydrogen as an energy carrier of high temperature reactor is 15.30 US$/MMBTU. Thus, both types seem to have strong competitiveness. (author)

Hydrogen production with a solar steam–methanol reformer and colloid nanocatalyst

KAUST Repository

Lee, Ming-Tsang

2010-01-01

In the present study a small steam-methanol reformer with a colloid nanocatalyst is utilized to produce hydrogen. Radiation from a focused continuous green light laser (514 nm wavelength) is used to provide the energy for steam-methanol reforming. Nanocatalyst particles, fabricated by using pulsed laser ablation technology, result in a highly active catalyst with high surface to volume ratio. A small novel reformer fabricated with a borosilicate capillary is employed to increase the local temperature of the reformer and thereby increase hydrogen production. The hydrogen production output efficiency is determined and a value of 5% is achieved. Experiments using concentrated solar simulator light as the radiation source are also carried out. The results show that hydrogen production by solar steam-methanol colloid nanocatalyst reforming is both feasible and promising. © 2009 Professor T. Nejat Veziroglu.

Nuclear energy for hydrogen production

International Nuclear Information System (INIS)

Verfondern, K.

2007-01-01

In the long term, H 2 production technologies will be strongly focusing on CO 2 -neutral or CO 2 -free methods. Nuclear with its virtually no air-borne pollutants emissions appears to be an ideal option for large-scale centralized H 2 production. It will be driven by major factors such as production rates of fossil fuels, political decisions on greenhouse gas emissions, energy security and independence of foreign oil uncertainties, or the economics of large-scale hydrogen production and transmission. A nuclear reactor operated in the heat and power cogeneration mode must be located in close vicinity to the consumer's site, i.e., it must have a convincing safety concept of the combined nuclear/ chemical production plant. A near-term option of nuclear hydrogen production which is readily available is conventional low temperature electrolysis using cheap off-peak electricity from present nuclear power plants. This, however, is available only if the share of nuclear in power production is large. But as fossil fuel prices will increase, the use of nuclear outside base-load becomes more attractive. Nuclear steam reforming is another important near-term option for both the industrial and the transportation sector, since principal technologies were developed, with a saving potential of some 35 % of methane feedstock. Competitiveness will benefit from increasing cost level of natural gas. The HTGR heated steam reforming process which was simulated in pilot plants both in Germany and Japan, appears to be feasible for industrial application around 2015. A CO 2 emission free option is high temperature electrolysis which reduces the electricity needs up to about 30 % and could make use of high temperature heat and steam from an HTGR. With respect to thermochemical water splitting cycles, the processes which are receiving presently most attention are the sulfur-iodine, the Westinghouse hybrid, and the calcium-bromine (UT-3) cycles. Efficiencies of the S-I process are in the

The hydrogen production; La production d'hydrogene

Energy Technology Data Exchange (ETDEWEB)

Aujollet, P.; Goldstein, St. [CEA Cadarach, Dir. de l' Energie Nucleaire, 13 - Saint Paul lez Durance (France); Lucchese, P. [CEA Fontenay aux Roses, Dir. des Nouvelles Technologies de l' Energie, 92 (France)

2002-07-01

This paper gives an overview on the implementing of the hydrogen as substitution fuel in the transportation sector. It presents also the problems of this fuel storage and exploitation and describes the production modes and their safety. It also presents the main lines of the japan HTGR program. (A.L.B.)

Hydrogen production and purification for fuel cell applications

Science.gov (United States)

Chin, Soo Yin

The increased utilization of proton-exchange membrane (PEM) fuel cells as an alternative to internal combustion engines is expected to increase the demand for hydrogen, which is used as the energy source in these systems. Currently, production of hydrogen for fuel cells is primarily achieved via steam reforming, partial oxidation or autothermal reforming of natural gas, or steam reforming of methanol. However, in all of these processes CO is a by-product that must be subsequently removed due to its adverse effects on the Pt-based electrocatalysts of the PEM fuel cell. Our efforts have focused on production of CO-free hydrogen via catalytic decomposition of hydrocarbons and purification of H2 via the preferential oxidation of CO. The catalytic decomposition of hydrocarbons is an attractive alternative for the production of H2. Previous studies utilizing methane have shown that this approach can indeed produce CO-free hydrogen, with filamentous carbon formed as the by-product and deposited on the catalyst. We have further extended this approach to the decomposition of ethane. In addition to hydrogen and filamentous carbon however, methane is also formed in this case as a by-product. Studies conducted at different temperatures and space velocities suggest that hydrogen is the primary product while methane is formed in a secondary step. Ni/SiO2 catalysts are active for ethane decomposition at temperatures above 500°C. Although the yield of hydrogen increases with temperature, the catalyst deactivation rate also accelerates at higher temperatures. The preferential oxidation of CO is currently used for the purification of CO-contaminated hydrogen streams due to its efficiency and simplicity. Conventional Pt catalysts used for this reaction have been shown to effectively remove CO, but have limited selectivity (i.e., substantial amounts of H 2 also react with O2). Our work focused on alternative catalytic materials, such as Ru and bimetallic Ru-based catalysts (Pt-Ru, Ru

Limits for hydrogen production of a solar - hydrogen system in Cuernavaca, Mexico

International Nuclear Information System (INIS)

Arriaga, H.L.G.; Gutierrez, S.L.; Cano, U.

2006-01-01

In this work experimental data are used in order to estimate the production of hydrogen as a function of irradiance of a direct-interconnection of solar panel system with a SPE (Solid Polymer Electrolyte) electrolyzer (also Solar-Hydrogen system). The solar - hydrogen system, consists of a photovoltaic solar array of 36 panels (75 Watts each) of monocrystalline silicon interconnected with an electrolyzer stack of 25 cells (around 100 cm 2 of geometrical area) with a maximum hydrogen production of 1 Nm 3 /h. By the use of voltage, current density, energy consumption values of the whole solar-hydrogen system, an average efficiency up to 5% was estimated and an average of 3,800 NL of hydrogen per day can be expected. Also the maximum hydrogen production for the months of July and December (sunniest and least sunny months in the location) is predicted. (authors)

Limits for hydrogen production of a solar - hydrogen system in Cuernavaca, Mexico

Energy Technology Data Exchange (ETDEWEB)

Arriaga, H.L.G.; Gutierrez, S.L.; Cano, U. [Instituto de Investigaciones Electricas Av. Reforma 113, col. Palmira c.p.62490 Cuernavaca Morelos (Mexico)

2006-07-01

In this work experimental data are used in order to estimate the production of hydrogen as a function of irradiance of a direct-interconnection of solar panel system with a SPE (Solid Polymer Electrolyte) electrolyzer (also Solar-Hydrogen system). The solar - hydrogen system, consists of a photovoltaic solar array of 36 panels (75 Watts each) of monocrystalline silicon interconnected with an electrolyzer stack of 25 cells (around 100 cm{sup 2} of geometrical area) with a maximum hydrogen production of 1 Nm{sup 3}/h. By the use of voltage, current density, energy consumption values of the whole solar-hydrogen system, an average efficiency up to 5% was estimated and an average of 3,800 NL of hydrogen per day can be expected. Also the maximum hydrogen production for the months of July and December (sunniest and least sunny months in the location) is predicted. (authors)

Appraisal of bio-hydrogen production schemes

International Nuclear Information System (INIS)

Bent Sorensen

2006-01-01

Work is ongoing on several schemes of biological hydrogen production. At one end is the genetic modification of biological systems (such as algae or cyanobacteria) to produce hydrogen from photosynthesis, instead of the energy-rich compounds (such as NADPH 2 ) normally constituting the endpoint of the transformations through the photo-systems. A second route is to collect and use the biomass produced by normal plant growth processes in a separate step that produces hydrogen. This may be done similar to biogas production by fermentation, where the endpoint is methane (plus CO 2 and minor constituents). Hydrogen could be the outcome of a secondary process starting from methane, involving any of the conventional methods of hydrogen production from natural gas. An alternative to fermentation is gasification of the biomass, followed by a shift-reaction leading to hydrogen. I compare advantages and disadvantages of these three routes, notably factors such as system efficiency, cost and environmental impacts, and also compare them to liquid biofuels. (author)

Preliminary Cost Estimates for Nuclear Hydrogen Production: HTSE System

International Nuclear Information System (INIS)

Yang, K. J.; Lee, K. Y.; Lee, T. H.

2008-01-01

KAERI is now focusing on the research and development of the key technologies required for the design and realization of a nuclear hydrogen production system. As a preliminary study of cost estimates for nuclear hydrogen systems, the hydrogen production costs of the nuclear energy sources benchmarking GTMHR and PBMR are estimated in the necessary input data on a Korean specific basis. G4-ECONS was appropriately modified to calculate the cost for hydrogen production of HTSE (High Temperature Steam Electrolysis) process with VHTR (Very High Temperature nuclear Reactor) as a thermal energy source. The estimated costs presented in this paper show that hydrogen production by the VHTR could be competitive with current techniques of hydrogen production from fossil fuels if CO 2 capture and sequestration is required. Nuclear production of hydrogen would allow large-scale production of hydrogen at economic prices while avoiding the release of CO 2 . Nuclear production of hydrogen could thus become the enabling technology for the hydrogen economy. The major factors that would affect the cost of hydrogen were also discussed

Catalytic glycerol steam reforming for hydrogen production

International Nuclear Information System (INIS)

Dan, Monica; Mihet, Maria; Lazar, Mihaela D.

2015-01-01

Hydrogen production from glycerol by steam reforming combine two major advantages: (i) using glycerol as raw material add value to this by product of bio-diesel production which is obtained in large quantities around the world and have a very limited utilization now, and (ii) by implication of water molecules in the reaction the efficiency of hydrogen generation is increased as each mol of glycerol produces 7 mol of H 2 . In this work we present the results obtained in the process of steam reforming of glycerol on Ni/Al 2 O 3 . The catalyst was prepared by wet impregnation method and characterized through different methods: N 2 adsorption-desorption, XRD, TPR. The catalytic study was performed in a stainless steel tubular reactor at atmospheric pressure by varying the reaction conditions: steam/carbon ratio (1-9), gas flow (35 ml/min -133 ml/min), temperature (450-650°C). The gaseous fraction of the reaction products contain: H 2 , CH 4 , CO, CO 2 . The optimum reaction conditions as resulted from this study are: temperature 550°C, Gly:H 2 O ratio 9:1 and Ar flow 133 ml/min. In these conditions the glycerol conversion to gaseous products was 43% and the hydrogen yield was 30%

LARGE-SCALE PRODUCTION OF HYDROGEN BY NUCLEAR ENERGY FOR THE HYDROGEN ECONOMY

International Nuclear Information System (INIS)

SCHULTZ, K.R.; BROWN, L.C.; BESENBRUCH, G.E.; HAMILTON, C.J.

2003-01-01

OAK B202 LARGE-SCALE PRODUCTION OF HYDROGEN BY NUCLEAR ENERGY FOR THE HYDROGEN ECONOMY. The ''Hydrogen Economy'' will reduce petroleum imports and greenhouse gas emissions. However, current commercial hydrogen production processes use fossil fuels and releases carbon dioxide. Hydrogen produced from nuclear energy could avoid these concerns. The authors have recently completed a three-year project for the US Department of Energy whose objective was to ''define an economically feasible concept for production of hydrogen, by nuclear means, using an advanced high-temperature nuclear reactor as the energy source''. Thermochemical water-splitting, a chemical process that accomplishes the decomposition of water into hydrogen and oxygen, met this objective. The goal of the first phase of this study was to evaluate thermochemical processes which offer the potential for efficient, cost-effective, large-scale production of hydrogen and to select one for further detailed consideration. The authors selected the Sulfur-Iodine cycle, In the second phase, they reviewed all the basic reactor types for suitability to provide the high temperature heat needed by the selected thermochemical water splitting cycle and chose the helium gas-cooled reactor. In the third phase they designed the chemical flowsheet for the thermochemical process and estimated the efficiency and cost of the process and the projected cost of producing hydrogen. These results are summarized in this paper

Chemistry - Toward efficient hydrogen production at surfaces

DEFF Research Database (Denmark)

Nørskov, Jens Kehlet; Christensen, Claus H.

2006-01-01

Calculations are providing a molecular picture of hydrogen production on catalytic surfaces and within enzymes, knowledge that may guide the design of new, more efficient catalysts for the hydrogen economy.......Calculations are providing a molecular picture of hydrogen production on catalytic surfaces and within enzymes, knowledge that may guide the design of new, more efficient catalysts for the hydrogen economy....

Continuous Hydrogen Production from Agricultural Wastewaters at Thermophilic and Hyperthermophilic Temperatures.

Science.gov (United States)

Ramos, Lucas Rodrigues; Silva, Edson Luiz

2017-06-01

The objective of this study was to investigate the effects of hydraulic retention time (HRT) (8 to 0.5 h) and temperature (55 to 75 °C) in two anaerobic fluidized bed reactors (AFBR) using cheese whey (AFBR-CW = 10,000 mg sugars L -1 ) and vinasse (AFBR-V = 10,000 mg COD L -1 ) as substrates. Decreasing the HRT to 0.5 h increased the hydrogen production rates in both reactors, with maximum values of 5.36 ± 0.81 L H 2 h -1 L -1 in AFBR-CW and 0.71 ± 0.16 L H 2 h -1 L -1 in AFBR-V. The optimal conditions for hydrogen production were the HRT of 4 h and temperature of 65 °C in AFBR-CW, observing maximum hydrogen yield (HY) of 5.51 ± 0.37 mmol H 2 g COD -1 . Still, the maximum HY in AFBR-V was 1.64 ± 0.22 mmol H 2 g COD -1 at 4 h and 55 °C. However, increasing the temperature to 75 °C reduced the hydrogen production in both reactors. Methanol and butyric, acetic, and lactic acids were the main metabolites at temperatures of 55 and 65 °C, favoring the butyric and acetic metabolic pathways of hydrogen production. The increased productions of lactate, propionate, and methanol at 75 °C indicate that the hydrogen-producing bacteria in the thermophilic inoculum were inhibited under hyperthermophilic conditions.

High-rate fermentative hydrogen production from beverage wastewater

International Nuclear Information System (INIS)

Sivagurunathan, Periyasamy; Sen, Biswarup; Lin, Chiu-Yue

2015-01-01

Highlights: • Hybrid immobilized-bacterial cells show stable operation over 175 days. • Low HRT of 1.5 h shows peak hydrogen production rate of 55 L/L-d. • Electricity generation is 9024 kW-d from 55 L/L-d hydrogen using beverage wastewater. • Granular sludge formed only at 2–3 h HRT with presence of Selenomonas sp. - Abstract: Hydrogen production from beverage industry wastewater (20 g/L hexose equivalent ) using an immobilized cell reactor with a continuous mode of operation was studied at various hydraulic retention times (HRT, 8–1.5 h). Maximum hydrogen production rate (HPR) of 55 L/L-d was obtained at HRT 1.5 h (an organic loading of 320 g/L-d hexose equivalent ). This HPR value is much higher than those of other industrial wastewaters employed in fermentative hydrogen production. The cell biomass concentration peaked at 3 h HRT with a volatile suspended solids (VSS) concentration of 6.31 g/L (with presence of self-flocculating Selenomonas sp.), but it dropped to 3.54 gVSS/L at 1.5 h HRT. With the shortening of HRT, lactate concentration increased but the concentration of the dominant metabolite butyrate did not vary significantly. The Clostridium species dynamics was not significantly affected, but total microbial community structure changed with respect to HRT variation as evident from PCR–DGGE analyses. Analysis of energy production rate suggests that beverage wastewater is a high energy yielding feedstock, and can replace 24% of electricity consumption in a model beverage industry

The US department of energy programme on hydrogen production

International Nuclear Information System (INIS)

Paster, M.D.

2004-01-01

production will be more cost effective, but distributed production will still play a role. Utilization of nuclear and renewable technologies inherently addresses greenhouse gas emission directly. The use of fossil fuels requires the development of carbon dioxide sequestration technology to enable a hydrogen economy that also addresses climate change concerns. Ultimately, a spectrum of feedstocks and technologies for hydrogen production will be necessary to address energy security and climate change concerns. The DOE Hydrogen Program will address multiple feedstock and technology options to provide effective and efficient hydrogen production for the short term and the long term. The U. S. DOE Hydrogen Program is contained within the Offices of Nuclear Energy, Fossil Energy, and Energy Efficiency and Renewable Energy that are now working synergistically together to accomplish the overall program goals. The potential benefits of a hydrogen economy are immense. They include increased energy security through the use of domestic and renewable energy feedstocks and a dramatic reduction in green house gas and other criteria air pollutants. (author)

Technical Integration of Nuclear Hydrogen Production Technology

International Nuclear Information System (INIS)

Lee, Ki Young; Chang, J. H.; Park, J. K.

2007-06-01

These works focus on the development of attainment indices for nuclear hydrogen key technologies, the analysis of the hydrogen production process and the performance estimation for hydrogen production system, and the assessment of the nuclear hydrogen production economy. To estimate the attainments of the key technologies in progress with the performance goals of GIF, itemized are the attainment indices based on SRP published in VHTR R and D steering committee of Gen-IV. For assessing the degree of attainments in comparison with the final goals of VHTR technologies in progress of researches, subdivided are the prerequisite items conformed to the NHDD concepts established in a preconceptual design in 2005. The codes for analyzing the hydrogen production economy are developed for calculating the unit production cost of nuclear hydrogen. We developed basic R and D quality management methodology to meet design technology of VHTR's needs. By putting it in practice, we derived some problems and solutions. We distributed R and D QAP and Q and D QAM to each teams and these are in operation. Computer simulations are performed for estimating the thermal efficiency for the electrodialysis component likely to adapting as one of the hydrogen production system in Korea and EED-SI process known as the key components of the hydrogen production systems. Using the commercial codes, the process diagrams and the spread-sheets were produced for the Bunsen reaction process, Sulphuric Acid dissolution process and HI dissolution process, respectively, which are the key components composing of the SI process

Challenges for renewable hydrogen production

International Nuclear Information System (INIS)

Levin, D.B.; Chahine, R.

2009-01-01

The increasing demand for H 2 for heavy oil upgrading, desulfurization and upgrading of conventional petroleum, and for production of ammonium, in addition to the projected demand for H 2 as a transportation fuel and portable power, will require H 2 production on a massive scale. Increased production of H 2 by current technologies will consume greater amounts of conventional hydrocarbons (primarily natural gas) which in turn will generate greater greenhouse gas emissions. Production of H 2 from renewable sources derived from agricultural or other waste streams offers the possibility to contribute to the production capacity with lower or no net greenhouse gas emissions (without carbon sequestration technologies), increasing the flexibility and improving the economics of distributed and semi-centralized reforming. Electrolysis, thermo-catalytic, and biological production can be easily adapted to on-site decentralized production of H 2 , circumventing the need to establish a large and costly distribution infrastructure. Each of these H 2 production technologies, however, faces technical challenges, including conversion efficiencies, feedstock type, and the need to safely integrate H 2 production systems with H 2 purification and storage technologies. These issues are being addressed by H2CAN, a recently launched NSERC funded national strategic network in hydrogen production, purification, storage, infrastructure and safety. (author)

Bio-hydrogen Production Potential from Market Waste

Directory of Open Access Journals (Sweden)

Lanna Jaitalee

2010-07-01

Full Text Available This research studied bio-hydrogen production from vegetable waste from a fresh market in order to recover energy. A series of batch experiments were conducted to investigate the effects of initial volatile solids concentration on the bio-hydrogen production process. Lab bench scale anaerobic continuous stirred-tank reactors (CSTR were used to study the effect of substrate and sludge inoculation on hydrogen production. Three different concentrations of initial total volatile solids (TVS of organic waste were varied from 2%, 3% and 5% respectively. The pH was controlled at 5.5 for all batches in the experiment. The results showed that bio-hydrogen production depended on feed-substrate concentration. At initial TVS content of 3%, the highest hydrogen production was achieved at a level of 0.59 L-H2/L at pH 5.5. The maximum hydrogen yield was 15.3 ml H2/g TVS or 8.5 ml H2/g COD. The composition of H2 in the biogas ranged from 28.1-30.9% and no CH4 was detected in all batch tests.

Microwave plasma for hydrogen production from liquids

Directory of Open Access Journals (Sweden)

Czylkowski Dariusz

2016-06-01

Full Text Available The hydrogen production by conversion of liquid compounds containing hydrogen was investigated experimentally. The waveguide-supplied metal cylinder-based microwave plasma source (MPS operated at frequency of 915 MHz at atmospheric pressure was used. The decomposition of ethanol, isopropanol and kerosene was performed employing plasma dry reforming process. The liquid was introduced into the plasma in the form of vapour. The amount of vapour ranged from 0.4 to 2.4 kg/h. Carbon dioxide with the flow rate ranged from 1200 to 2700 NL/h was used as a working gas. The absorbed microwave power was up to 6 kW. The effect of absorbed microwave power, liquid composition, liquid flow rate and working gas fl ow rate was analysed. All these parameters have a clear influence on the hydrogen production efficiency, which was described with such parameters as the hydrogen production rate [NL(H2/h] and the energy yield of hydrogen production [NL(H2/kWh]. The best achieved experimental results showed that the hydrogen production rate was up to 1116 NL(H2/h and the energy yield was 223 NL(H2 per kWh of absorbed microwave energy. The results were obtained in the case of isopropanol dry reforming. The presented catalyst-free microwave plasma method can be adapted for hydrogen production not only from ethanol, isopropanol and kerosene, but also from different other liquid compounds containing hydrogen, like gasoline, heavy oils and biofuels.

Methane and hydrogen production from crop biomass through anaerobic digestion

Energy Technology Data Exchange (ETDEWEB)

Pakarinen, O.

2011-07-01

The feasibility of methane and hydrogen production from energy crops through anaerobic digestion was evaluated in this thesis. The effects of environmental conditions, e.g. pH and temperature, as well as inoculum source on H{sub 2} yield were studied in batch assays. In addition, the effects of pre-treatments on methane and hydrogen yield as well as the feasibility of two-stage H{sub 2} + CH{sub 4} production was evaluated. Moreover, the effect of storage on methane yield of grasses was evaluated. Monodigestion of grass silage for methane production was studied, as well as shifting the methanogenic process to hydrogenic. Hydrogen production from grass silage and maize was shown to be possible with heat-treated inoculum in batch assays, with highest H{sub 2} yields of 16.0 and 9.9 ml gVS{sub added}-1 from untreated grass silage and maize, respectively. Pre-treatments (NaOH, HCl and water-extraction) showed some potential in increasing H{sub 2} yields, while methane yields were not affected. Two-stage H{sub 2} + CH{sub 4} producing process was shown to improve CH{sub 4} yields when compared to traditional one-stage CH{sub 4} process. Methane yield from grass silage monodigestion in continuously stirred tank reactor (CSTR) with organic loading rate (OLR) of 2 kgVS (m3d)-1 and hydraulic retention time (HRT) of 30 days was at most 218 l kgVS{sub fed}-1. Methanogenic process was shifted to hydrogenic by increasing the OLR to 10 kgVS (m3d)-1 and shortening the HRT to 6 days. Highest H{sub 2} yield from grass silage was 42 l kgVS{sub fed}-1 with a maximum H{sub 2} content of 24 %. Energy crops can be successfully stored even for prolonged periods without decrease in methane yield. However, under sub-optimal storage conditions loss in volatile solids (VS) content and methane yield can occur. According to present results energy crops such as grass silage and maize can be converted to hydrogen or methane in AD process. Hydrogen energy yields are typically only 2-5 % of the

Hydrogen production by using Rhodobacter capsulatus mutants with genetically modified electron transfer chains

Energy Technology Data Exchange (ETDEWEB)

OEztuerk, Yavuz; Yuecel, Meral; Guenduez, Ufuk [Department of Biology, Middle East Technical University, Ankara (Turkey); Daldal, Fevzi [Department of Biology, Plant Science Institute, University of Pennsylvania, Philadelphia, PA 19104-6018 (United States); Mandaci, Sevnur [TUEBITAK Research Institute for Genetic Engineering and Biotechnology, Gebze Kocaeli 41470 (Turkey); Tuerker, Lemi [Department of Chemistry, Middle East Technical University, Ankara (Turkey); Eroglu, Inci [Department of Chemical Engineering, Middle East Technical University, Ankara (Turkey)

2006-09-15

In Rhodobacter capsulatus excess reducing equivalents generated by organic acid oxidation is consumed to reduce protons into hydrogen by the activity of nitrogenase. Nitrogenase serves as a redox-balancing tool and is activated by the RegB/RegA global regulatory system during photosynthetic growth. The terminal cytochrome cbb{sub 3} oxidase and the redox state of the cyclic photosynthetic electron transfer chain serve redox signaling to the RegB/RegA regulatory systems in Rhodobacter. In this study, hydrogen production of various R. capsulatus strains harboring the genetically modified electron carrier cytochromes or lacking the cyt cbb{sub 3} oxidase or the quinol oxidase were compared with the wild type. The results indicated that hydrogen production of mutant strains with modified electron carrier cytochromes decreased 3- to 4-fold, but the rate of hydrogen production increased significantly in a cbb{sub 3}{sup -} mutant. Moreover, hydrogen production efficiency of various R. capsulatus strains further increased by inactivation of uptake hydrogenase genes. (author)

Present status of research on hydrogen energy and perspective of HTGR hydrogen production system

Energy Technology Data Exchange (ETDEWEB)

Miyamoto, Yoshiaki; Ogawa, Masuro; Akino, Norio [Japan Atomic Energy Research Inst., Oarai, Ibaraki (Japan). Oarai Research Establishment] [and others

2001-03-01

A study was performed to make a clear positioning of research and development on hydrogen production systems with a High Temperature Gas-cooled Reactor (HTGR) under currently promoting at the Japan Atomic Energy Research Institute through a grasp of the present status of hydrogen energy, focussing on its production and utilization as an energy in future. The study made clear that introduction of safe distance concept for hydrogen fire and explosion was practicable for a HTGR hydrogen production system, including hydrogen properties and need to provide regulations applying to handle hydrogen. And also generalization of hydrogen production processes showed technical issues of the HTGR system. Hydrogen with HTGR was competitive to one with fossil fired system due to evaluation of production cost. Hydrogen is expected to be used as promising fuel of fuel cell cars in future. In addition, the study indicated that there were a large amount of energy demand alternative to high efficiency power generation and fossil fuel with nuclear energy through the structure of energy demand and supply in Japan. Assuming that hydrogen with HTGR meets all demand of fuel cell cars, an estimation would show introduction of the maximum number of about 30 HTGRs with capacity of 100 MWt from 2020 to 2030. (author)

Hydrogen Production Technical Team Roadmap

Energy Technology Data Exchange (ETDEWEB)

None

2013-06-01

The Hydrogen Production Technical Team Roadmap identifies research pathways leading to hydrogen production technologies that produce near-zero net greenhouse gas (GHG) emissions from highly efficient and diverse renewable energy sources. This roadmap focuses on initial development of the technologies, identifies their gaps and barriers, and describes activities by various U.S. Department of Energy (DOE) offices to address the key issues and challenges.

Perturbation of formate pathway for hydrogen production by expressions of formate hydrogen lyase and its transcriptional activator in wild Enterobacter aerogenes and its mutants

Energy Technology Data Exchange (ETDEWEB)

Lu, Yuan; Zhao, Hongxin; Zhang, Chong; Lai, Qiheng; Xing, Xin-Hui [Institute of Biochemical Engineering, Department of Chemical Engineering, Tsinghua University, Beijing 100084 (China)

2009-06-15

To examine perturbation effects of formate pathway on hydrogen productivity in Enterobacter aerogenes (Ea), formate dehydrogenase FDH-H gene (fdhF) and formate hydrogen lyase activator protein FHLA gene (fhlA) originated from Escherichia coli, were overexpressed in the wild strain Ea, its hycA-deleted mutant (A) by knockout the formate hydrogen lyase repressor and hybO-deleted mutant (O) by knockout of the uptake hydrogenase, respectively. Overexpression of fdhF and fhlA promoted cell growth and volumetric hydrogen production rates of all the strains, and the hydrogen production per gram cell dry weight (CDW) for Ea, A and O was increased by 38.5%, 21.8% and 5.25%, respectively. The fdhF and fhlA overexpression improved the hydrogen yield per mol glucose of strains Ea and A, but declined that of strain O. The increase of hydrogen yield of the strain Ea with fdhF and fhlA expression was mainly attributed to the increase of formate pathway, while for the mutant A, the improved hydrogen yield with fdhF and fhlA expression was mainly due to the increase of NADH pathway. Analysis of the metabolites and ratio of ethanol-to-acetate showed that the cellular redox state balance and energy level were also changed for these strains by fdhF and fhlA expression. These findings demonstrated that the hydrogen production was not only dependent on the hydrogenase genes, but was also affected by the regulation of the whole metabolism. Therefore, fdhF and fhlA expression in different strains of E. aerogenes could exhibit different perturbation effects on the metabolism and the hydrogen productivity. (author)

Improvements in Fermentative Biological Hydrogen Production Through Metabolic Engineering

Energy Technology Data Exchange (ETDEWEB)

Hallenbeck, P. C.; Ghosh, D.; Sabourin-Provost, G.

2009-07-01

Dramatically rising oil prices and increasing awareness of the dire environmental consequences of fossil fuel use, including startling effects of climate change, are refocusing attention world-wide on the search for alternative fuels. Hydrogen is poised to become an important future energy carrier. Renewable hydrogen production is pivotal in making it a truly sustainable replacement for fossil fuels. (Author)

Improvements in Fermentative Biological Hydrogen Production Through Metabolic Engineering

International Nuclear Information System (INIS)

Hallenbeck, P. C.; Ghosh, D.; Sabourin-Provost, G.

2009-01-01

Dramatically rising oil prices and increasing awareness of the dire environmental consequences of fossil fuel use, including startling effects of climate change, are refocusing attention world-wide on the search for alternative fuels. Hydrogen is poised to become an important future energy carrier. Renewable hydrogen production is pivotal in making it a truly sustainable replacement for fossil fuels. (Author)

Biological hydrogen production from industrial wastewaters

Energy Technology Data Exchange (ETDEWEB)

Peixoto, Guilherme; Pantoja Filho, Jorge Luis Rodrigues; Zaiat, Marcelo [Universidade de Sao Paulo (EESC/USP), Sao Carlos, SP (Brazil). School of Engineering. Dept. Hydraulics and Sanitation], Email: peixoto@sc.usp.br

2010-07-01

This research evaluates the potential for producing hydrogen in anaerobic reactors using industrial wastewaters (glycerol from bio diesel production, wastewater from the parboilization of rice, and vinasse from ethanol production). In a complementary experiment the soluble products formed during hydrogen production were evaluated for methane generation. The assays were performed in batch reactors with 2 liters volume, and sucrose was used as a control substrate. The acidogenic inoculum was taken from a packed-bed reactor used to produce hydrogen from a sucrose-based synthetic substrate. The methanogenic inoculum was taken from an upflow anaerobic sludge blanket reactor treating poultry slaughterhouse wastewater. Hydrogen was produced from rice parboilization wastewater (24.27 ml H{sub 2} g{sup -1} COD) vinasse (22.75 ml H{sub 2} g{sup -1} COD) and sucrose (25.60 ml H{sub 2} g{sup -1} COD), while glycerol only showed potential for methane generation. (author)

LARGE-SCALE HYDROGEN PRODUCTION FROM NUCLEAR ENERGY USING HIGH TEMPERATURE ELECTROLYSIS

International Nuclear Information System (INIS)

O'Brien, James E.

2010-01-01

Hydrogen can be produced from water splitting with relatively high efficiency using high-temperature electrolysis. This technology makes use of solid-oxide cells, running in the electrolysis mode to produce hydrogen from steam, while consuming electricity and high-temperature process heat. When coupled to an advanced high temperature nuclear reactor, the overall thermal-to-hydrogen efficiency for high-temperature electrolysis can be as high as 50%, which is about double the overall efficiency of conventional low-temperature electrolysis. Current large-scale hydrogen production is based almost exclusively on steam reforming of methane, a method that consumes a precious fossil fuel while emitting carbon dioxide to the atmosphere. Demand for hydrogen is increasing rapidly for refining of increasingly low-grade petroleum resources, such as the Athabasca oil sands and for ammonia-based fertilizer production. Large quantities of hydrogen are also required for carbon-efficient conversion of biomass to liquid fuels. With supplemental nuclear hydrogen, almost all of the carbon in the biomass can be converted to liquid fuels in a nearly carbon-neutral fashion. Ultimately, hydrogen may be employed as a direct transportation fuel in a 'hydrogen economy.' The large quantity of hydrogen that would be required for this concept should be produced without consuming fossil fuels or emitting greenhouse gases. An overview of the high-temperature electrolysis technology will be presented, including basic theory, modeling, and experimental activities. Modeling activities include both computational fluid dynamics and large-scale systems analysis. We have also demonstrated high-temperature electrolysis in our laboratory at the 15 kW scale, achieving a hydrogen production rate in excess of 5500 L/hr.

Catalytic glycerol steam reforming for hydrogen production

Energy Technology Data Exchange (ETDEWEB)

Dan, Monica, E-mail: monica.dan@itim-cj.ro; Mihet, Maria, E-mail: maria.mihet@itim-cj.ro; Lazar, Mihaela D., E-mail: diana.lazar@itim-cj.ro [National Institute for Research and Development of Isotopic and Molecular Technologies, 67-103 Donat Street, 400293 Cluj Napoca (Romania)

2015-12-23

Hydrogen production from glycerol by steam reforming combine two major advantages: (i) using glycerol as raw material add value to this by product of bio-diesel production which is obtained in large quantities around the world and have a very limited utilization now, and (ii) by implication of water molecules in the reaction the efficiency of hydrogen generation is increased as each mol of glycerol produces 7 mol of H{sub 2}. In this work we present the results obtained in the process of steam reforming of glycerol on Ni/Al{sub 2}O{sub 3}. The catalyst was prepared by wet impregnation method and characterized through different methods: N{sub 2} adsorption-desorption, XRD, TPR. The catalytic study was performed in a stainless steel tubular reactor at atmospheric pressure by varying the reaction conditions: steam/carbon ratio (1-9), gas flow (35 ml/min -133 ml/min), temperature (450-650°C). The gaseous fraction of the reaction products contain: H{sub 2}, CH{sub 4}, CO, CO{sub 2}. The optimum reaction conditions as resulted from this study are: temperature 550°C, Gly:H{sub 2}O ratio 9:1 and Ar flow 133 ml/min. In these conditions the glycerol conversion to gaseous products was 43% and the hydrogen yield was 30%.

Safety assessment of VHTR hydrogen production system against fire, explosion and acute toxicity

International Nuclear Information System (INIS)

Murakami, Tomoyuki; Nishihara, Tetsuo; Kunitomi, Kazuhiko

2008-01-01

The Japan Atomic Energy Agency has been developing a nuclear hydrogen production system by using heat from the Very High Temperature Reactor (VHTR). This system will handle a large amount of combustible gas and toxic gas. The risk from fire, explosion and acute toxic exposure caused by an accident involving chemical material release in a hydrogen production system is assessed. It is important to ensure the safety of the nuclear plant, and the risks for public health should be sufficiently small. This report provides the basic policy for the safety evaluation in cases of accident involving fire, explosion and toxic material release in a hydrogen production system. Preliminary safety analysis of a commercial-sized VHTR hydrogen production system, GTHTR300C, is performed. This analysis provides us with useful information on the separation distance between a nuclear plant and a hydrogen production system and a prospect that an accident in a hydrogen production system does not significantly increase the risks of the public. (author)

New concepts in hydrogen production in Iceland

International Nuclear Information System (INIS)

Arnason, B.; Sigfusson, T.I.; Jonsson, V.K.

1993-01-01

The paper presents some new concepts of hydrogen production in Iceland for domestic use and export. A brief overview of the Icelandic energy consumption and available resources is given. The cost of producing hydrogen by electrolysis is calculated for various alternatives such as plant size, load factors and electricity cost. Comparison is made between the total cost of liquid hydrogen delivered to Europe from Iceland and from Northern America, showing that liquid hydrogen delivered to Europe from Iceland would be 9% less expensive. This assumes conventional technology. New technologies are suggested in the paper and different scenarios for geothermally assisted hydrogen production and liquefaction are discussed. It is estimated that the use of geothermal steam would lead to 19% lower hydrogen gas production costs. By analysing the Icelandic fishing fleet, a very large consumer of imported fuel, it is argued that a transition of fuel technology from oil to hydrogen may be a feasible future option for Iceland and a testing ground for changing fuel technology. (Author)

Renewable solar hydrogen production and utilization

International Nuclear Information System (INIS)

Bakos, J.

2006-01-01

There is a tremendous opportunity to generate large quantities of hydrogen from low grade and economical sources of methane including landfill gas, biogas, flare gas, and coal bed methane. The environmental benefits of generating hydrogen using renewable energy include significant greenhouse gas and air contaminant reductions. Solar Hydrogen Energy Corporation (SHEC LABS) recently constructed and demonstrated a Dry Fuel Reforming (DFR) hydrogen generation system that is powered primarily by sunlight focusing-mirrors in Tempe, Arizona. The system comprises a solar mirror array, a temperature controlling shutter system, and two thermo-catalytic reactors to convert methane, carbon dioxide, and water into hydrogen. This process has shown that solar hydrogen generation is feasible and cost-competitive with traditional hydrogen production. The presentation will provide the following: An overview of the results of the testing conducted in Tempe, Arizona; A look at the design and installation of the scaled-up technology site at a landfill site in Canada; An examination of the economic and environmental benefits of renewable hydrogen production using solar energy

Exergetic life cycle assessment of hydrogen production from renewables

Science.gov (United States)

Granovskii, Mikhail; Dincer, Ibrahim; Rosen, Marc A.

Life cycle assessment is extended to exergetic life cycle assessment and used to evaluate the exergy efficiency, economic effectiveness and environmental impact of producing hydrogen using wind and solar energy in place of fossil fuels. The product hydrogen is considered a fuel for fuel cell vehicles and a substitute for gasoline. Fossil fuel technologies for producing hydrogen from natural gas and gasoline from crude oil are contrasted with options using renewable energy. Exergy efficiencies and greenhouse gas and air pollution emissions are evaluated for all process steps, including crude oil and natural gas pipeline transportation, crude oil distillation and natural gas reforming, wind and solar electricity generation, hydrogen production through water electrolysis, and gasoline and hydrogen distribution and utilization. The use of wind power to produce hydrogen via electrolysis, and its application in a fuel cell vehicle, exhibits the lowest fossil and mineral resource consumption rate. However, the economic attractiveness, as measured by a "capital investment effectiveness factor," of renewable technologies depends significantly on the ratio of costs for hydrogen and natural gas. At the present cost ratio of about 2 (per unit of lower heating value or exergy), capital investments are about five times lower to produce hydrogen via natural gas rather than wind energy. As a consequence, the cost of wind- and solar-based electricity and hydrogen is substantially higher than that of natural gas. The implementation of a hydrogen fuel cell instead of an internal combustion engine permits, theoretically, an increase in a vehicle's engine efficiency of about of two times. Depending on the ratio in engine efficiencies, the substitution of gasoline with "renewable" hydrogen leads to (a) greenhouse gas (GHG) emissions reductions of 12-23 times for hydrogen from wind and 5-8 times for hydrogen from solar energy, and (b) air pollution (AP) emissions reductions of 38

Effect of substrate concentration on hydrogen production by photo-fermentation in the pilot-scale baffled bioreactor.

Science.gov (United States)

Lu, Chaoyang; Zhang, Zhiping; Zhou, Xuehua; Hu, Jianjun; Ge, Xumeng; Xia, Chenxi; Zhao, Jia; Wang, Yi; Jing, Yanyan; Li, Yameng; Zhang, Quanguo

2018-01-01

Effect of substrate concentration on photo-fermentative hydrogen production was studied with a self-designed 4m 3 pilot-scale baffled photo-fermentative hydrogen production reactor (BPHR). The relationships between parameters, such as hydrogen production rate (HPR, mol H 2 /m 3 /d), hydrogen concentration, pH value, oxidation-reduction potential, biomass concentration (volatile suspended solids, VSS) and reducing sugar concentration, during the photo-fermentative hydrogen production process were investigated. The highest HPR of 202.64±8.83mol/m 3 /d was achieved in chamber #3 at a substrate concentration of 20g/L. Hydrogen contents were in the range of 42.19±0.94%-49.71±0.27%. HPR increased when organic loading rate was increased from 3.3 to 20g/L/d, then decreased when organic loading rate was further increased to 25g/L/d. A maximum HPR of 148.65±4.19mol/m 3 /d was obtained when organic loading rate was maintained at 20g/L/d during continuous bio-hydrogen production. Copyright © 2017 Elsevier Ltd. All rights reserved.

Hydrogen production processes

International Nuclear Information System (INIS)

2003-01-01

The goals of this first Gedepeon workshop on hydrogen production processes are: to stimulate the information exchange about research programs and research advances in the domain of hydrogen production processes, to indicate the domains of interest of these processes and the potentialities linked with the coupling of a nuclear reactor, to establish the actions of common interest for the CEA, the CNRS, and eventually EDF, that can be funded in the framework of the Gedepeon research group. This document gathers the slides of the 17 presentations given at this workshop and dealing with: the H 2 question and the international research programs (Lucchese P.); the CEA's research program (Lucchese P., Anzieu P.); processes based on the iodine/sulfur cycle: efficiency of a facility - flow-sheets, efficiencies, hard points (Borgard J.M.), R and D about the I/S cycle: Bunsen reaction (Colette S.), R and D about the I/S cycle: the HI/I 2 /H 2 O system (Doizi D.), demonstration loop/chemical engineering (Duhamet J.), materials and corrosion (Terlain A.); other processes under study: the Westinghouse cycle (Eysseric C.), other processes under study at the CEA (UT3, plasma,...) (Lemort F.), database about thermochemical cycles (Abanades S.), Zn/ZnO cycle (Broust F.), H 2 production by cracking, high temperature reforming with carbon trapping (Flamant G.), membrane technology (De Lamare J.); high-temperature electrolysis: SOFC used as electrolyzers (Grastien R.); generic aspects linked with hydrogen production: technical-economical evaluation of processes (Werkoff F.), thermodynamic tools (Neveu P.), the reactor-process coupling (Aujollet P.). (J.S.)

Temperature dependence of anti-hydrogen production in the ATHENA experiment

CERN Document Server

Bonomi, G; Amsler, Claude; Bouchta, A; Bowe, P; Carraro, C; Cesar, C L; Charlton, M; Doser, Michael; Filippini, V; Fontana, A; Fujiwara, M C; Funakoshi, R; Genova, P; Hangst, J S; Hayano, R S; Jørgensen, L V; Lagomarsino, V; Landua, Rolf; Lindelöf, D; Lodi-Rizzini, E; Macri, M; Madsen, N; Montagna, P; Pruys, H S; Regenfus, C; Riedler, P; Rotondi, A; Testera, G; Variola, A; Van der Werf, D P

2004-01-01

The ATHENA experiment recently produced the first sample of cold anti-hydrogen atoms by mixing cold plasmas of anti-protons and positrons. The temperature of the positron plasma was increased by controlled RF heating and the anti-hydrogen production rate was measured. Preliminary results are presented. (8 refs).

[Study on the Emission Spectrum of Hydrogen Production with Microwave Discharge Plasma in Ethanol Solution].

Science.gov (United States)

Sun, Bing; Wang, Bo; Zhu, Xiao-mei; Yan, Zhi-yu; Liu, Yong-jun; Liu, Hui

2016-03-01

Hydrogen is regarded as a kind of clean energy with high caloricity and non-pollution, which has been studied by many experts and scholars home and abroad. Microwave discharge plasma shows light future in the area of hydrogen production from ethanol solution, providing a new way to produce hydrogen. In order to further improve the technology and analyze the mechanism of hydrogen production with microwave discharge in liquid, emission spectrum of hydrogen production by microwave discharge plasma in ethanol solution was being studied. In this paper, plasma was generated on the top of electrode by 2.45 GHz microwave, and the spectral characteristics of hydrogen production from ethanol by microwave discharge in liquid were being studied using emission spectrometer. The results showed that a large number of H, O, OH, CH, C2 and other active particles could be produced in the process of hydrogen production from ethanol by microwave discharge in liquid. The emission spectrum intensity of OH, H, O radicals generated from ethanol is far more than that generated from pure water. Bond of O-H split by more high-energy particles from water molecule was more difficult than that from ethanol molecule, so in the process of hydrogen production by microwave discharge plasma in ethanol solution; the main source of hydrogen was the dehydrogenation and restructuring of ethanol molecules instead of water decomposition. Under the definite external pressure and temperature, the emission spectrum intensity of OH, H, O radicals increased with the increase of microwave power markedly, but the emission spectrum intensity of CH, C2 active particles had the tendency to decrease with the increase of microwave power. It indicated that the number of high energy electrons and active particles high energy electron energy increased as the increase of microwave power, so more CH, C2 active particles were split more thoroughly.

Methods and systems for the production of hydrogen

Science.gov (United States)

Oh, Chang H [Idaho Falls, ID; Kim, Eung S [Ammon, ID; Sherman, Steven R [Augusta, GA

2012-03-13

Methods and systems are disclosed for the production of hydrogen and the use of high-temperature heat sources in energy conversion. In one embodiment, a primary loop may include a nuclear reactor utilizing a molten salt or helium as a coolant. The nuclear reactor may provide heat energy to a power generation loop for production of electrical energy. For example, a supercritical carbon dioxide fluid may be heated by the nuclear reactor via the molten salt and then expanded in a turbine to drive a generator. An intermediate heat exchange loop may also be thermally coupled with the primary loop and provide heat energy to one or more hydrogen production facilities. A portion of the hydrogen produced by the hydrogen production facility may be diverted to a combustor to elevate the temperature of water being split into hydrogen and oxygen by the hydrogen production facility.

Efficient STEP (solar thermal electrochemical photo) production of hydrogen - an economic assessment

Energy Technology Data Exchange (ETDEWEB)

Licht, Stuart [Department of Chemistry, George Washington University, Ashburn, VA 20147 (United States); Solar Institute, George Washington University, Washington, DC 20052 (United States); Chitayat, Olivia; Bergmann, Harry; Dick, Andrew; Ayub, Hina [Solar Institute, George Washington University, Washington, DC 20052 (United States); Ghosh, Susanta [Department of Chemistry, George Washington University, Ashburn, VA 20147 (United States); Department of Chemistry, Visva-Bharati, Santiniketan (India)

2010-10-15

A consideration of the economic viability of hydrogen fuel production is important in the STEP (Solar Thermal Electrochemical Photo) production of hydrogen fuel. STEP is an innovative way to decrease costs and increase the efficiency of hydrogen fuel production, which is a synergistic process that can use concentrating photovoltaics (CPV) and solar thermal energy to drive a high temperature, low voltage, electrolysis (water-splitting), resulting in H{sub 2} at decreased energy and higher solar efficiency. This study provides evidence that the STEP system is an economically viable solution for the production of hydrogen. STEP occurs at both higher electrolysis and solar conversion efficiencies than conventional room temperature photovoltaic (PV) generation of hydrogen. This paper probes the economic viability of this process, by comparing four different systems: (1) 10% or (2) 14% flat plate PV driven aqueous alkaline electrolysis H{sub 2} production, (3) 25% CPV driven molten electrolysis H{sub 2} production, and (4) 35% CPV driven solid oxide electrolysis H{sub 2} production. The molten and solid oxide electrolysers are high temperature systems that can make use of light, normally discarded, for heating. This significantly increases system efficiency. Using levelized cost analysis, this study shows significant cost reduction using the STEP system. The total price per kg of hydrogen is shown to decrease from 5.74 to 4.96 to 3.01 to 2.61 with the four alternative systems. The advanced STEP plant requires less than one seventh of the land area of the 10% flat cell plant. To generate the 216 million kg H{sub 2}/year required by 1 million fuel cell vehicles, the 35% CPV driven solid oxide electrolysis requires a plant only 9.6 mi{sup 2} in area. While PV and electrolysis components dominate the cost of conventional PV generated hydrogen, they do not dominate the cost of the STEP-generated hydrogen. The lower cost of STEP hydrogen is driven by residual distribution and

Biological hydrogen production by dark fermentation: challenges and prospects towards scaled-up production.

Science.gov (United States)

RenNanqi; GuoWanqian; LiuBingfeng; CaoGuangli; DingJie

2011-06-01

Among different technologies of hydrogen production, bio-hydrogen production exhibits perhaps the greatest potential to replace fossil fuels. Based on recent research on dark fermentative hydrogen production, this article reviews the following aspects towards scaled-up application of this technology: bioreactor development and parameter optimization, process modeling and simulation, exploitation of cheaper raw materials and combining dark-fermentation with photo-fermentation. Bioreactors are necessary for dark-fermentation hydrogen production, so the design of reactor type and optimization of parameters are essential. Process modeling and simulation can help engineers design and optimize large-scale systems and operations. Use of cheaper raw materials will surely accelerate the pace of scaled-up production of biological hydrogen. And finally, combining dark-fermentation with photo-fermentation holds considerable promise, and has successfully achieved maximum overall hydrogen yield from a single substrate. Future development of bio-hydrogen production will also be discussed. Copyright © 2011 Elsevier Ltd. All rights reserved.

Development of interface technology for nuclear hydrogen production system

International Nuclear Information System (INIS)

Lee, Ki Young; Park, J. K.; Chang, J. H.

2012-06-01

These works focus on the development of attainment indices for nuclear hydrogen key technologies, the analysis of the hydrogen production process and the performance estimation for hydrogen production systems, and the assessment of the nuclear hydrogen production economy. The codes for analyzing the hydrogen production economy are developed for calculating the unit production cost of nuclear hydrogen. We developed basic R and D quality management methodology to meet design technology of VHTR's needs. By putting it in practice, we derived some problems and solutions. We distributed R and D QAP and Q and D QAM to each teams and these are in operation. Computer simulations are performed for estimating the thermal efficiency for the electrodialysis component likely to adapting as one of the hydrogen production system in Korea and EED-SI process known as the key components of the hydrogen production systems. Using the commercial codes, the process diagrams and the spread-sheets were produced for the Bunsen reaction process, Sulphuric Acid dissolution process and HI dissolution process, respectively, which are the key components composing of the SI process

Negative hydrogen ion production mechanisms

Energy Technology Data Exchange (ETDEWEB)

Bacal, M. [UPMC, LPP, Ecole Polytechnique, UMR CNRS 7648, Palaiseau (France); Wada, M. [School of Science and Engineering, Doshisha University, Kyoto 610-0321 (Japan)

2015-06-15

Negative hydrogen/deuterium ions can be formed by processes occurring in the plasma volume and on surfaces facing the plasma. The principal mechanisms leading to the formation of these negative ions are dissociative electron attachment to ro-vibrationally excited hydrogen/deuterium molecules when the reaction takes place in the plasma volume, and the direct electron transfer from the low work function metal surface to the hydrogen/deuterium atoms when formation occurs on the surface. The existing theoretical models and reported experimental results on these two mechanisms are summarized. Performance of the negative hydrogen/deuterium ion sources that emerged from studies of these mechanisms is reviewed. Contemporary negative ion sources do not have negative ion production electrodes of original surface type sources but are operated with caesium with their structures nearly identical to volume production type sources. Reasons for enhanced negative ion current due to caesium addition to these sources are discussed.

Research and development of HTTR hydrogen production systems

International Nuclear Information System (INIS)

Shiozawa, Shusaku; Ogawa, Masuro; Inagaki, Yoshiyuki; Onuki, Kaoru; Takeda, Tetsuaki; Nishihara, Tetsuo; Hayashi, Koji; Kubo, Shinji; Inaba, Yoshitomo; Ohashi, Hirofumi

2002-01-01

The Japan Atomic Energy Research Institute (JAERI) has constructed the High Temperature Engineering Test Reactor (HTTR) with a thermal output of 30MW and a reactor out let coolant temper at ure of 950 .deg. C. There search and development (R and D) program on nuclear production of hydrogen was started on January in 1997 as a study consigned by Ministry of Education, Culture, Sports, Science and Technology. A hydrogen production system connected to the HTTR is being designed to be able to produce hydrogen of about 4000m 3 /h by steam reforming of natural gas, using a nuclear heat of 10MW supplied by the HTTR hydrogen production system. In order to confirm controllability, safety and performance of key components in the HTTR hydrogen production system, the facility for the out-of-pile test was constructed on the scale of approximately 1/30 of the HTTR hydrogen production system. In parallel to the out-of-pile test, the following tests as essential problem, a corrosion test of a reforming tube, a permeation test of hydrogen isotopes through heat exchanger and reforming tubes, and an integrity test of a high-temperature isolation valve are carried out to obtain detailed data for safety review and development of analytical codes. Other basis studies on the hydrogen production technology of thermochemical water splitting called an iodine sulfur (IS) process, has been carried out for more effective and various uses of nuclear heat. This paper describes the present status and a future plan on the R and D of the HTTR hydrogen production systems in JAERI

Modeling of combustion products composition of hydrogen-containing fuels

International Nuclear Information System (INIS)

Assad, M.S.

2010-01-01

Due to the usage of entropy maximum principal the algorithm and the program of chemical equilibrium calculation concerning hydrogen--containing fuels are devised. The program enables to estimate the composition of combustion products generated in the conditions similar to combustion conditions in heat engines. The program also enables to reveal the way hydrogen fraction in the conditional composition of the hydrocarbon-hydrogen-air mixture influences the harmful components content. It is proven that molecular hydrogen in the mixture is conductive to the decrease of CO, CO 2 and CH x concentration. NO outlet increases due to higher combustion temperature and N, O, OH concentrations in burnt gases. (authors)

Research on hydrogen production system

International Nuclear Information System (INIS)

Nakagiri, Toshio

2002-07-01

Hydrogen is closely watched for environmental issues in recent years. In this research, hydrogen production systems and production techniques are widely investigated, and selected some hydrogen production process which have high validity for FBR system. Conclusions of the investigation are shown below. (1) Water-electrolysis processes and steam reform processes at low temperatures are already realized in other fields, so they well be easily adopted for FBR system. FBR system has no advantage when compared with other systems, because water-electrolysis processes can be adopted for other electricity generation system. On the other hand, FBR system has an advantage when steam reforming processes at low temperatures will be adopted, because steam reforming processes at 550-600degC can't be adopted for LWR. (2) Thermochemical processes will be able to adopted for FBR when process temperature will be lowered and material problems solved, because their efficiencies are expected high. Radiolysis processes which use ray (for example, gamma rya) emitted in reactor can be generate hydrogen easily, so they will be able to be adopted for FBR if splitting efficiency will be higher. Further investigation and R and D to realize these processes are considered necessary. (author)

Hydrogen Production by Thermophilic Fermentation

NARCIS (Netherlands)

Niel, van E.W.J.; Willquist, K.; Zeidan, A.A.; Vrije, de T.; Mars, A.E.; Claassen, P.A.M.

2012-01-01

Of the many ways hydrogen can be produced, this chapter focuses on biological hydrogen production by thermophilic bacteria and archaea in dark fermentations. The thermophiles are held as promising candidates for a cost-effective fermentation process, because of their relatively high yields and broad

Designer proton-channel transgenic algae for photobiological hydrogen production

Science.gov (United States)

Lee, James Weifu [Knoxville, TN

2011-04-26

A designer proton-channel transgenic alga for photobiological hydrogen production that is specifically designed for production of molecular hydrogen (H.sub.2) through photosynthetic water splitting. The designer transgenic alga includes proton-conductive channels that are expressed to produce such uncoupler proteins in an amount sufficient to increase the algal H.sub.2 productivity. In one embodiment the designer proton-channel transgene is a nucleic acid construct (300) including a PCR forward primer (302), an externally inducible promoter (304), a transit targeting sequence (306), a designer proton-channel encoding sequence (308), a transcription and translation terminator (310), and a PCR reverse primer (312). In various embodiments, the designer proton-channel transgenic algae are used with a gas-separation system (500) and a gas-products-separation and utilization system (600) for photobiological H.sub.2 production.

Decentralized and direct solar hydrogen production: Towards a hydrogen economy in MENA region

Energy Technology Data Exchange (ETDEWEB)

Bensebaa, Farid; Khalfallah, Mohamed; Ouchene, Majid

2010-09-15

Hydrogen has certainly some advantages in spite of its high cost and low efficiency when compared to other energy vectors. Solar energy is an abundant, clean and renewable source of energy, currently competing with fossil fuel for water heating without subsidy. Photo-electrochemical, thermo-chemicals and photo-biological processes for hydrogen production processes have been demonstrated. These decentralised hydrogen production processes using directly solar energy do not require expensive hydrogen infrastructure for packaging and delivery in the short and medium terms. MENA region could certainly be considered a key area for a new start to a global deployment of hydrogen economy.

Hydrogen production from water: Recent advances in photosynthesis research

Energy Technology Data Exchange (ETDEWEB)

Greenbaum, E.; Lee, J.W. [Oak Ridge National Lab., TN (United States). Chemical Technology Div.

1997-12-31

The great potential of hydrogen production by microalgal water splitting is predicated on quantitative measurement of the algae`s hydrogen-producing capability, which is based on the following: (1) the photosynthetic unit size of hydrogen production; (2) the turnover time of photosynthetic hydrogen production; (3) thermodynamic efficiencies of conversion of light energy into the Gibbs free energy of molecular hydrogen; (4) photosynthetic hydrogen production from sea water using marine algae; (5) the potential for research advances using modern methods of molecular biology and genetic engineering to maximize hydrogen production. ORNL has shown that sustained simultaneous photoevolution of molecular hydrogen and oxygen can be performed with mutants of the green alga Chlamydomonas reinhardtii that lack a detectable level of the Photosystem I light reaction. This result is surprising in view of the standard two-light reaction model of photosynthesis and has interesting scientific and technological implications. This ORNL discovery also has potentially important implications for maximum thermodynamic conversion efficiency of light energy into chemical energy by green plant photosynthesis. Hydrogen production performed by a single light reaction, as opposed to two, implies a doubling of the theoretically maximum thermodynamic conversion efficiency from {approx}10% to {approx}20%.

System Evaluation and Economic Analysis of a HTGR Powered High-Temperature Electrolysis Hydrogen Production Plant

International Nuclear Information System (INIS)

McKellar, Michael G.; Harvego, Edwin A.; Gandrik, Anastasia A.

2010-01-01

A design for a commercial-scale high-temperature electrolysis (HTE) plant for hydrogen production has been developed. The HTE plant is powered by a high-temperature gas-cooled reactor (HTGR) whose configuration and operating conditions are based on the latest design parameters planned for the Next Generation Nuclear Plant (NGNP). The current HTGR reference design specifies a reactor power of 600 MWt, with a primary system pressure of 7.0 MPa, and reactor inlet and outlet fluid temperatures of 322 C and 750 C, respectively. The power conversion unit will be a Rankine steam cycle with a power conversion efficiency of 40%. The reference hydrogen production plant operates at a system pressure of 5.0 MPa, and utilizes a steam-sweep system to remove the excess oxygen that is evolved on the anode (oxygen) side of the electrolyzer. The overall system thermal-to-hydrogen production efficiency (based on the higher heating value of the produced hydrogen) is 40.4% at a hydrogen production rate of 1.75 kg/s and an oxygen production rate of 13.8 kg/s. An economic analysis of this plant was performed with realistic financial and cost estimating assumptions. The results of the economic analysis demonstrated that the HTE hydrogen production plant driven by a high-temperature helium-cooled nuclear power plant can deliver hydrogen at a cost of $3.67/kg of hydrogen assuming an internal rate of return, IRR, of 12% and a debt to equity ratio of 80%/20%. A second analysis shows that if the power cycle efficiency increases to 44.4%, the hydrogen production efficiency increases to 42.8% and the hydrogen and oxygen production rates are 1.85 kg/s and 14.6 kg/s respectively. At the higher power cycle efficiency and an IRR of 12% the cost of hydrogen production is $3.50/kg.

Roles Prioritization of Hydrogen Production Technologies for Promoting Hydrogen Economy in the Current State of China

DEFF Research Database (Denmark)

Ren, Jingzheng; Gao, Suzhao; Tan, Shiyu

2015-01-01

Hydrogen production technologies play an important role in the hydrogen economy of China. However, the roles of different technologies played in promoting the development of hydrogen economy are different. The role prioritization of various hydrogen production technologies is of vital importance...... information. The prioritization results by using the proposed method demonstrated that the technologies of coal gasification with CO2 capture and storage and hydropower-based water electrolysis were regarded as the two most important hydrogen production pathways for promoting the development of hydrogen...... for the stakeholders/decision-makers to plan the development of hydrogen economy in China and to allocate the finite R&D budget reasonably. In this study, DPSIR framework was firstly used to identify the key factors concerning the priorities of various hydrogen production technologies; then, a fuzzy group decision...

A Study on Methodology of Assessment for Hydrogen Explosion in Hydrogen Production Facility

International Nuclear Information System (INIS)

Jung, Gun Hyo

2007-02-01

Due to the exhaustion of fossil fuel as energy sources and international situation insecurity for political factor, unstability of world energy market is rising, consequently, a substitute energy development have been required. Among substitute energy to be discussed, producing hydrogen from water by nuclear energy which does not release carbon is a very promising technology. Very high temperature gas cooled reactor is expected to be utilized since the procedure of producing hydrogen requires high temperature over 1000 .deg. C. Hydrogen production facility using very high temperature gas cooled reactor lies in situation of high temperature and corrosion which makes hydrogen release easily. In case of hydrogen release, there lies a danger of explosion. Moreover explosion not only has a bad influence upon facility itself but very high temperature gas cooled reactor which also result in unsafe situation that might cause serious damage. However, from point of thermal-hydraulics view, long distance makes low efficiency result. In this study, therefore, outlines of hydrogen production using nuclear energy is researched. Several methods for analyzing the effects of hydrogen explosion upon high temperature gas cooled reactor are reviewed. Reliability physics model which is appropriate for assessment is used. Using this model, leakage probability, rupture probability and structure failure probability of very high temperature gas cooled reactor is evaluated classified by detonation volume and distance. Also based on standard safety criteria which is a value of 1x10 -6 , the safety distance between very high temperature and hydrogen production facility is calculated. In the future, assessment for characteristic of very high temperature gas cooled reactor, capacity to resist pressure from outside hydrogen explosion and overpressure for large amount of detonation volume in detail is expected to identify more precise distance using reliability physics model in this paper. This

Scenarios of hydrogen production from wind power

Energy Technology Data Exchange (ETDEWEB)

Klaric, Mario

2010-09-15

Since almost total amount of hydrogen is currently being produced from natural gas, other ways of cleaner and 'more renewable' production should be made feasible in order to make benchmarks for total 'hydrogen economy'. Hydrogen production from wind power combined with electrolysis imposes as one possible framework for new economy development. In this paper various wind-to-hydrogen scenarios were calculated. Cash flows of asset based project financing were used as decision making tool. Most important parameters were identified and strategies for further research and development and resource allocation are suggested.

Status of hydrogen production by nuclear power

International Nuclear Information System (INIS)

Chang, Jong Wa; Yoo, Kun Joong; Park, Chang Kue

2001-07-01

Hydrogen production methods, such as electrolysis, thermochemical method, biological method, and photochemical method, are introduced in this report. Also reviewed are current status of the development of High Temperatrue Gas Coooled Reactor, and it application for hydrogen production

Evaluation of Nuclear Hydrogen Production System

International Nuclear Information System (INIS)

Park, Won Seok; Park, C. K.; Park, J. K. and others

2006-04-01

The major objective of this work is tow-fold: one is to develop a methodology to determine the best VHTR types for the nuclear hydrogen demonstration project and the other is to evaluate the various hydrogen production methods in terms of the technical feasibility and the effectiveness for the optimization of the nuclear hydrogen system. Both top-tier requirements and design requirements have been defined for the nuclear hydrogen system. For the determination of the VHTR type, a comparative study on the reference reactors, PBR and PBR, was conducted. Based on the analytic hierarchy process (AHP) method, a systematic methodology has been developed to compare the two VHTR types. Another scheme to determine the minimum reactor power was developed as well. Regarding the hydrogen production methods, comparison indices were defined and they were applied to the IS (Iodine-Sulfur) scheme, Westinghouse process, and the, high-temperature electrolysis method. For the HTE, IS, and MMI cycle, the thermal efficiency of hydrogen production were systematically evaluated. For the IS cycle, an overall process was identified and the functionality of some key components was identified. The economy of the nuclear hydrogen was evaluated, relative to various primary energy including natural gas coal, grid-electricity, and renewable. For the international collaborations, two joint research centers were established: NH-JRC between Korea and China and NH-JDC between Korea and US. Currently, several joint researches are underway through the research centers

Annex 15 of the IEA Hydrogen Implementing Agreement : Photobiological hydrogen production

Energy Technology Data Exchange (ETDEWEB)

Lindblad, P. [Uppsala Univ., Uppsala (Sweden)]|[International Energy Agency, Paris (France)

2004-07-01

Task 15 of the Hydrogen Implementation Agreement of the International Energy Agency is to advance the science of biophotosynthesis of hydrogen, which is the biological production of hydrogen from water and sunlight using microalgal photosynthesis. A practical process for biophotolysis would result in an innovative biological source of sustainable and environmentally benign renewable energy source. Japan, Norway, Sweden and the United States initially committed to the project. Since then Canada, the Netherlands and the United Kingdom have joined. The current task is to produce hydrogen from both green algae and cyanobacteria with focus on early-stage applied research on biophotolysis processes with intermediate carbon dioxide fixation. Significant advances have also occurred in the scientific field of cyanobacterial biohydrogen. Cyanobacteria has enzymes that metabolise hydrogen. Photosynthetic cyanobacteria have simple nutritional requirements and can grow in air, water, or mineral salts with light as the only source of energy. This research will help provide the advances needed to achieve practical efficiencies and cost objectives of biological hydrogen production. tabs., figs.

Hydrogen Production from Nuclear Energy via High Temperature Electrolysis

International Nuclear Information System (INIS)

James E. O'Brien; Carl M. Stoots; J. Stephen Herring; Grant L. Hawkes

2006-01-01

This paper presents the technical case for high-temperature nuclear hydrogen production. A general thermodynamic analysis of hydrogen production based on high-temperature thermal water splitting processes is presented. Specific details of hydrogen production based on high-temperature electrolysis are also provided, including results of recent experiments performed at the Idaho National Laboratory. Based on these results, high-temperature electrolysis appears to be a promising technology for efficient large-scale hydrogen production

Fusion reactors for hydrogen production via electrolysis

International Nuclear Information System (INIS)

Fillo, J.A.; Powell, J.R.; Steinberg, M.

1979-01-01

The decreasing availability of fossil fuels emphasizes the need to develop systems which will produce synthetic fuel to substitute for and supplement the natural supply. An important first step in the synthesis of liquid and gaseous fuels is the production of hydrogen. Thermonuclear fusion offers an inexhaustible source of energy for the production of hydrogen from water. Depending on design, electric generation efficiencies of approx. 40 to 60% and hydrogen production efficiencies by high temperature electrolysis of approx. 50 to 70% are projected for fusion reactors using high temperature blankets

Microstructured reactors for hydrogen production

Energy Technology Data Exchange (ETDEWEB)

Aartun, Ingrid

2005-07-01

Small scale hydrogen production by partial oxidation (POX) and oxidative steam reforming (OSR) have been studied over Rh-impregnated microchannel Fecralloy reactors and alumina foams. Trying to establish whether metallic microchannel reactors have special advantages for hydrogen production via catalytic POX or OSR with respect to activity, selectivity and stability was of special interest. The microchannel Fecralloy reactors were oxidised at 1000 deg C to form a {alpha}-Al2O3 layer in the channels in order to enhance the surface area prior to impregnation. Kr-BET measurements showed that the specific surface area after oxidation was approximately 10 times higher than the calculated geometric surface area. Approximately 1 mg Rh was deposited in the channels by impregnation with an aqueous solution of RhCl3. Annular pieces (15 mm o.d.,4 mm i.d., 14 mm length) of extruded {alpha}-Al2O3 foams were impregnated with aqueous solutions of Rh(NO3)3 to obtain 0.01, 0.05 and 0.1 wt.% loadings, as predicted by solution uptake. ICP-AES analyses showed that the actual Rh loadings probably were higher, 0.025, 0.077 and 0.169 wt.% respectively. One of the microchannel Fecralloy reactors and all Al2O3 foams were equipped with a channel to allow for temperature measurement inside the catalytic system. Temperature profiles obtained along the reactor axes show that the metallic microchannel reactor is able to minimize temperature gradients as compared to the alumina foams. At sufficiently high furnace temperature, the gas phase in front of the Rh/Al2O3/Frecralloy microchannel reactor and the 0.025 wt.% Rh/Al2O3 foams ignites. Gas phase ignition leads to lower syngas selectivity and higher selectivity to total oxidation products and hydrocarbon by-products. Before ignition of the gas phase the hydrogen selectivity is increased in OSR as compared to POX, the main contribution being the water-gas shift reaction. After gas phase ignition, increased formation of hydrocarbon by-products

Thermo-economic analysis of integrated membrane-SMR ITM-oxy-combustion hydrogen and power production plant

International Nuclear Information System (INIS)

Sanusi, Yinka S.; Mokheimer, Esmail M.A.; Habib, Mohamed A.

2017-01-01

Highlights: •A methane reforming reactor integrated to an oxy-combustion plant is proposed. •Co-production of power and hydrogen was investigated and presented. •Optimal thermo-economic operating conditions of the system were identified and presented. •The ion transport membrane oxygen separation unit has the highest capital cost. •The combustor has the highest exergy destruction. -- Abstract: The demand for hydrogen has greatly increased in the last decade due to the stringent regulations enacted to address environmental pollution concerns. Natural gas reforming is currently the most mature technology for large-scale hydrogen production. However, it is usually associated with greenhouse gas emissions. As part of the strategies to reduce greenhouse gas emissions, new designs need to be developed to integrate hydrogen production facilities that are based on natural gas reforming with carbon capture facilities. In this study, we carried out energy, exergy and economic analysis of hydrogen production in a steam methane reforming reactor integrated with an oxy-combustion plant for co-production of power and hydrogen. The results show that the overall system efficiency and hydrogen production efficiency monotonically increase with increasing the combustor exit temperature (CET), increasing the amount of hydrogen extracted and decreasing the auxiliary fuel added to the system. The optimal thermo-economic operating conditions of the system were obtained as reformer pressure of 15 bar, auxiliary fuel factor of 0.8 and hydrogen extraction factor of 0.6. The production cost of hydrogen using the proposed system, under these optimal operating conditions, is within the range suggested by the International Energy Agency (IEA). Further analysis shows that the capital cost of the membrane-air separation unit (ITM) has the major share in the total investment cost of the system and constitutes 37% of the total capital cost of the system at the CET of 1500 K. The exergy

Production of Hydrogen from Bio-ethanol

International Nuclear Information System (INIS)

Fabrice Giroudiere; Christophe Boyer; Stephane His; Robert Sanger; Kishore Doshi; Jijun Xu

2006-01-01

IFP and HyRadix are collaborating in the development of a new hydrogen production system from liquid feedstock such as bio-ethanol. Reducing greenhouse gas (GHG) emissions along with high hydrogen yield are the key objectives. Market application of the system will be hydrogen refueling stations as well as medium scale hydrogen consumers including the electronics, metals processing, and oils hydrogenation industries. The conversion of bio-ethanol to hydrogen will be performed within a co-developed process including an auto-thermal reformer working under pressure. The technology will produce high-purity hydrogen with ultralow CO content. The catalytic auto-thermal reforming technology combines the exothermic and endothermic reaction and leads to a highly efficient heat integration. The development strategy to reach a high hydrogen yield target with the bio-ethanol hydrogen generator is presented. (authors)

Conceptual design of the HTTR-IS hydrogen production system

International Nuclear Information System (INIS)

Sakaba, Nariaki; Sato, Hiroyuki; Hara, Teruo; Kato, Ryoma; Ohashi, Kazutaka; Nishihara, Tetsuo; Kunitomi, Kazuhiko

2007-08-01

Since hydrogen produced by nuclear should be economically competitive compared with other methods in a hydrogen society, it is important to build hydrogen production system to be coupled with the reactor as a conventional chemical plant. Japan Atomic Energy Agency started the safety study to establish a new safety philosophy to meet safety requirements for non-nuclear grade hydrogen production system. Also, structural concepts with integrating functions for the Bunsen reactor and sulphuric acid decomposer were proposed to reduce construction cost of the IS process hydrogen production system. In addition, HI decomposer which enables the process condition to be eased consisting of conventional materials and technologies was studied. Moreover, technical feasibility of the HTTR-IS system in which the hydrogen production rate of 1,000 Nm 3 /h by using the supplied heat of 10 MW from the intermediate heat exchanger of the HTTR was confirmed. This paper describes the conceptual design of the HTTR-IS hydrogen production system. (author)

Hydrogen Production Using Nuclear Energy

Energy Technology Data Exchange (ETDEWEB)

Verfondern, K. [Research Centre Juelich (Germany)

2013-03-15

world. In recent years, the scope of the IAEA's programme has been widened to include other more promising applications such as nuclear hydrogen production and higher temperature process heat applications. The OECD Nuclear Energy Agency, Euratom and the Generation IV International Forum have also shown interest in the non-electric applications of nuclear power based on future generation advanced and innovative nuclear reactors. This report was developed under an IAEA project with the objective of providing updated, balanced and objective information on the current status of hydrogen production processes using nuclear energy. It documents the state of the art of the development of hydrogen as an energy carrier in many Member States, as well as its corresponding production through the use of nuclear power. The report includes an introduction to the technology of nuclear process heat reactors as a means of producing hydrogen or other upgraded fuels, with a focus on high temperature reactor technology to achieve simultaneous generation of electricity and high temperature process heat and steam. Special emphasis is placed on the safety aspects of nuclear hydrogen production systems.

Photo-fermentational hydrogen production of Rhodobacter sp. KKU-PS1 isolated from an UASB reactor

Directory of Open Access Journals (Sweden)

Thitirut Assawamongkholsiri

2015-05-01

Conclusions: KKU-PS1 can produce hydrogen from at least 8 types of organic acids. By optimizing pH and temperature, a maximal hydrogen production by this strain was obtained. Additionally, by optimizing the light intensity, Rm was increased by approximately two fold and the lag phase of hydrogen production was shortened.

Comparative Analysis of Hydrogen Production Methods with Nuclear Reactors

International Nuclear Information System (INIS)

Morozov, Andrey

2008-01-01

Hydrogen is highly effective and ecologically clean fuel. It can be produced by a variety of methods. Presently the most common are through electrolysis of water and through the steam reforming of natural gas. It is evident that the leading method for the future production of hydrogen is nuclear energy. Several types of reactors are being considered for hydrogen production, and several methods exist to produce hydrogen, including thermochemical cycles and high-temperature electrolysis. In the article the comparative analysis of various hydrogen production methods is submitted. It is considered the possibility of hydrogen production with the nuclear reactors and is proposed implementation of research program in this field at the IPPE sodium-potassium eutectic cooling high temperature experimental facility (VTS rig). (authors)

How green are the hydrogen production processes?

International Nuclear Information System (INIS)

Miele, Ph.; Demirci, U.B.

2010-01-01

Molecular hydrogen is recognised as being one of the most promising fuels alternate to fossil fuels. Unfortunately it only exists combined with other elements like e.g. oxygen in the case of water and therefore has to be produced. Today various methods for producing molecular hydrogen are being investigated. Besides its energy potential, molecular hydrogen is regarded as being a green energy carrier because it can be produced from renewable sources and its combustion/oxidation generates water. However as it has to be produced its greenness merits a deeper discussion especially stressing on its production routes. The goal of the present article is to discuss the relative greenness of the various hydrogen production processes on the basis of the twelve principles of green chemistry. It is mainly showed that the combination 'renewable raw materials, biological or electrochemical methods, and renewable energies (e.g. solar or wind)' undeniably makes the hydrogen production green. (authors)

Hydrogen Production from Nuclear Energy

Science.gov (United States)

Walters, Leon; Wade, Dave

2003-07-01

During the past decade the interest in hydrogen as transportation fuel has greatly escalated. This heighten interest is partly related to concerns surrounding local and regional air pollution from the combustion of fossil fuels along with carbon dioxide emissions adding to the enhanced greenhouse effect. More recently there has been a great sensitivity to the vulnerability of our oil supply. Thus, energy security and environmental concerns have driven the interest in hydrogen as the clean and secure alternative to fossil fuels. Remarkable advances in fuel-cell technology have made hydrogen fueled transportation a near-term possibility. However, copious quantities of hydrogen must be generated in a manner independent of fossil fuels if environmental benefits and energy security are to be achieved. The renewable technologies, wind, solar, and geothermal, although important contributors, simply do not comprise the energy density required to deliver enough hydrogen to displace much of the fossil transportation fuels. Nuclear energy is the only primary energy source that can generate enough hydrogen in an energy secure and environmentally benign fashion. Methods of production of hydrogen from nuclear energy, the relative cost of hydrogen, and possible transition schemes to a nuclear-hydrogen economy will be presented.

Hydrogen Production by Water Electrolysis Via Photovoltaic Panel

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Hydrogen Production by Water Electrolysis Via Photovoltaic Panel

2016-07-01

Full Text Available Hydrogen fuel is a good alternative to fossil fuels. It can be produced using a clean energy without contaminated emissions. This work is concerned with experimental study on hydrogen production via solar energy. Photovoltaic module is used to convert solar radiation to electrical energy. The electrical energy is used for electrolysis of water into hydrogen and oxygen by using alkaline water electrolyzer with stainless steel electrodes. A MATLAB computer program is developed to solve a four-parameter-model and predict the characteristics of PV module under Baghdad climate conditions. The hydrogen production system is tested at different NaOH mass concentration of (50,100, 200, 300 gram. The maximum hydrogen production rate is 153.3 ml/min, the efficiency of the system is 20.88% and the total amount of hydrogen produced in one day is 220.752 liter.

Potential use of thermophilic dark fermentation effluents in photofermentative hydrogen production by Rhodobacter capsulatus

Energy Technology Data Exchange (ETDEWEB)

Ozgura, E.; Afsar, N.; Eroglu, I. [Middle East Technical University, Department of Chemical Engineering, 06531 Ankara (Turkey); De Vrije, T.; Claassen, P.A.M. [Wageningen UR, Agrotechnology and Food Sciences Group, Wageningen UR, P.O. Box 17, 6700 AA Wageningen (Netherlands); Yucel, M.; Gunduz, U. [Middle East Technical University, Department of Biology, 06531 Ankara (Turkey)

2010-12-15

Biological hydrogen production by a sequential operation of dark and photofermentation is a promising route to produce hydrogen. The possibility of using renewable resources, like biomass and agro-industrial wastes, provides a dual effect of sustainability in biohydrogen production and simultaneous waste removal. In this study, photofermentative hydrogen production on effluents of thermophilic dark fermentations on glucose, potato steam peels (PSP) hydrolysate and molasses was investigated in indoor, batch operated bioreactors. An extreme thermophile Caldicellulosiruptor saccharolyticus was used in the dark fermentation step, and Rhodobacter capsulatus (DSM1710) was used in the photofermentation step. Addition of buffer, Fe and Mo to dark fermentor effluents (DFEs) improved the overall efficiency of hydrogen production. The initial acetate concentration in the DFE needed to be adjusted to 30-40 mM by dilution to increase the yield of hydrogen in batch light-supported fermentations. The thermophilic DFEs are suitable for photofermentative hydrogen production, provided that they are supplemented with buffer and nutrients. The overall hydrogen yield of the two-step fermentations was higher than the yield of single step dark fermentations.

Production of hydrogen from by-products of food industries by rhodospirillaceae

Energy Technology Data Exchange (ETDEWEB)

Reh, U.

1983-11-01

The decomposition of organic substances from food-by-products as whey, beet sugar molasses, cane-sugar-molasses and potato-water by the Rhodospirillaceae Rp. capsulata, Rp. acidophila, Rm. vannielii, Rs. rubrum, and Rs. tenue to hydrogen and carbon dioxide were tested. In a pre-cultivation Lactobacillus bulgaricus converted the sugars of the by-products into lactic acid, which is easier in handling. Rs. rubrum was superior in producing hydrogen from this nutrient. It released from whey up to 56% of the substrate hydrogen, from beet sugar molasses 42%, from cane-sugar-molasses 89% and from potato-water 19%. Out-door-researches were made to evaluate the decrease of hydrogen yield under the influence of weather as well as day and night periods compared to the homogeneous conditions of the laboratory. From 200 m/sup 3/ whey, the daily output of a dairy, 4000 m/sup 3/ hydrogen corresponding to an energy equivalent of 1000 l fuel oil could be produced. To achieve this, 130 000 m/sup 2/ have to be covered with batch fermenters. These results show, that there is nearly no hope to decompose food by-products by Rhodospirillaceae in large scale technology, unless a new processing technology using a flow-fermenter and raising the hydrogen production significantly will be found.

Bio-hydrogen production from molasses by anaerobic fermentation in continuous stirred tank reactor

Science.gov (United States)

Han, Wei; Li, Yong-feng; Chen, Hong; Deng, Jie-xuan; Yang, Chuan-ping

2010-11-01

A study of bio-hydrogen production was performed in a continuous flow anaerobic fermentation reactor (with an available volume of 5.4 L). The continuous stirred tank reactor (CSTR) for bio-hydrogen production was operated under the organic loading rates (OLR) of 8-32 kg COD/m3 reactor/d (COD: chemical oxygen demand) with molasses as the substrate. The maximum hydrogen production yield of 8.19 L/d was obtained in the reactor with the OLR increased from 8 kg COD/m3 reactor/d to 24 kg COD/m3 d. However, the hydrogen production and volatile fatty acids (VFAs) drastically decreased at an OLR of 32 kg COD/m3 reactor/d. Ethanoi, acetic, butyric and propionic were the main liquid fermentation products with the percentages of 31%, 24%, 20% and 18%, which formed the mixed-type fermentation.

EVALUATING HYDROGEN PRODUCTION IN BIOGAS REFORMING IN A MEMBRANE REACTOR

Directory of Open Access Journals (Sweden)

F. S. A. Silva

2015-03-01

Full Text Available Abstract Syngas and hydrogen production by methane reforming of a biogas (CH4/CO2 = 2.85 using carbon dioxide was evaluated in a fixed bed reactor with a Pd-Ag membrane in the presence of a nickel catalyst (Ni 3.31% weight/γ-Al2O3 at 773 K, 823 K, and 873 K and 1.01×105 Pa. Operation with hydrogen permeation at 873 K increased the methane conversion to approximately 83% and doubled the hydrogen yield relative to operation without hydrogen permeation. A mathematical model was formulated to predict the evolution of the effluent concentrations. Predictions based on the model showed similar evolutions for yields of hydrogen and carbon monoxide at temperatures below 823 K for operations with and without the hydrogen permeation. The hydrogen yield reached approximately 21% at 823 K and 47% at 873 K under hydrogen permeation conditions.

Hydrogen production from solar energy

Science.gov (United States)

Eisenstadt, M. M.; Cox, K. E.

1975-01-01

Three alternatives for hydrogen production from solar energy have been analyzed on both efficiency and economic grounds. The analysis shows that the alternative using solar energy followed by thermochemical decomposition of water to produce hydrogen is the optimum one. The other schemes considered were the direct conversion of solar energy to electricity by silicon cells and water electrolysis, and the use of solar energy to power a vapor cycle followed by electrical generation and electrolysis. The capital cost of hydrogen via the thermochemical alternative was estimated at $575/kW of hydrogen output or $3.15/million Btu. Although this cost appears high when compared with hydrogen from other primary energy sources or from fossil fuel, environmental and social costs which favor solar energy may prove this scheme feasible in the future.

Effect of Heating Method on Hydrogen Production by Biomass Gasification in Supercritical Water

Directory of Open Access Journals (Sweden)

Qiuhui Yan

2014-01-01

Full Text Available The glucose as a test sample of biomass is gasified in supercritical water with different heating methods driven by renewable solar energy. The performance comparisons of hydrogen production of glucose gasification are investigated. The relations between temperature raising speed of reactant fluid, variation of volume fraction, combustion enthalpy, and chemical exergy of H2 of the product gases with reactant solution concentration are presented, respectively. The results show that the energy quality of product gases with preheating process is higher than that with no preheating unit for hydrogen production. Hydrogen production quantity and gasification rate of glucose decrease obviously with the increase of concentration of material in no preheating system.

Nuclear hydrogen production: re-examining the fusion option

International Nuclear Information System (INIS)

Baindur, S.

2007-01-01

This paper describes a scheme for nuclear hydrogen production by fusion. The basic idea is to use nuclear energy of the fuel (hydrogen plasma) to produce molecular hydrogen fro carbon-free hydrogen compounds. The hydrogen is then stored and utilized electrochemically in fuel cells or chemically as molecular hydrogen in internal combustion engines

Calculation of LUEC using HEEP Software for Nuclear Hydrogen Production Plant

Energy Technology Data Exchange (ETDEWEB)

Kim, Jongho; Lee, Kiyoung; Kim, Minhwan [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2015-05-15

To achieve the hydrogen economy, it is very important to produce a massive amount of hydrogen in a clean, safe and efficient way. Nuclear production of hydrogen would allow massive production of hydrogen at economic prices while avoiding environments pollution by reducing the release of carbon dioxide. A Very High Temperature Reactor (VHTR) is considered as an efficient reactor to couple with the thermo-chemical Sulfur Iodine (SI) cycle to achieve the hydrogen economy. HEEP(Hydrogen Economy Evaluation Program) is one of the software tools developed by IAEA to evaluate the economy of the nuclear hydrogen production system by estimating unit hydrogen production cost. In this paper, the LUHC (Levelized Unit Hydrogen Cost) is calculated by using HEEP for nuclear hydrogen production plant, which consists of 4 modules of 600 MWth VHTR coupled with SI process. The levelized unit hydrogen production cost(LUHC) was calculated by the HEEP software.

Production of JET fuel containing molecules of high hydrogen content

Directory of Open Access Journals (Sweden)

Tomasek Sz.

2017-12-01

Full Text Available The harmful effects of aviation can only be reduced by using alternative fuels with excellent burning properties and a high hydrogen content in the constituent molecules. Due to increasing plastic consumption the amount of the plastic waste is also higher. Despite the fact that landfill plastic waste has been steadily reduced, the present scenario is not satisfactory. Therefore, the aim of this study is to produce JET fuel containing an alternative component made from straight-run kerosene and the waste polyethylene cracking fraction. We carried out our experiments on a commercial NiMo/Al2O3/P catalyst at the following process parameters: T=200-300°C, P=40 bar, LHSV=1.0-3.0 h-1, hydrogen/hydrocarbon ratio= 400 Nm3/m3. We investigated the effects of the feedstocks and the process parameters on the product yields, the hydrodesulfurization and hydrodearomatization efficiencies, and the main product properties. The liquid product yields varied between 99.7-99.8%. As a result of the hydrogenation the sulfur (1-1780 mg/kg and the aromatic contents (9.0-20.5% of the obtained products and the values of their smoke points (26.0-34.7 mm fulfilled the requirements of JET fuel standard. Additionally, the concentration of paraffins increased in the products and the burning properties were also improved. The freezing points of the products were higher than -47°C, therefore product blending is needed.

Solar driven technologies for hydrogen production

Directory of Open Access Journals (Sweden)

Medojević Milovan M.

2016-01-01

Full Text Available Bearing in mind that the production of hydrogen based on renewable energy sources, without doubt, is an important aspect to be taken into account when considering the potential of this gas, where as particularly interesting technologies stand out the ones which are based on the use of solar energy to produce hydrogen. The goal of this paper provides basic technological trajectories, with the possibility of combining, for solar driven hydrogen production, such as: electrochemical, photochemical and thermochemical process. Furthermore, the paper presents an analysis of those technologies from a technical as well as economic point of view. In addition, the paper aims to draw attention to the fact that the generation of hydrogen using renewable energy should be imposed as a logical and proper way to store solar energy in the form of chemical energy.

Once-through hybrid sulfur process for nuclear hydrogen production

International Nuclear Information System (INIS)

Jeong, Y. H.

2008-01-01

Increasing concern about the global climate change spurs the development of low- or zero-carbon energy system. Nuclear hydrogen production by water electrolysis would be the one of the short-term solutions, but low efficiency and high production cost (high energy consumption) is the technical hurdle to be removed. In this paper the once-through sulfur process composed of the desulfurization and the water electrolysis systems is proposed. Electrode potential for the conventional water electrolysis (∼2.0 V) can be reduced significantly by the anode depolarization using sulfur dioxide: down to 0.6 V depending on the current density This depolarized electrolysis is the electrolysis step of the hybrid sulfur process originally proposed by the Westinghouse. However; recycling of sulfur dioxide requires a high temperature heat source and thus put another technical hurdle on the way to nuclear hydrogen production: the development of high temperature nuclear reactors and corresponding sulfuric acid decomposition system. By the once-through use of sulfur dioxide rather than the closed recycle, the hurdle can be removed. For the sulfur feed, the desulfurization system is integrated into the water electrolysis system. Fossil fuels include a few percent of sulfur by weight. During the refinement or energy conversion, most of the sulfur should be separated The separated sulfur can be fed to the water electrolysis system and the final product would be hydrogen and sulfuric acid, which is number one chemical in the world by volume. Lowered electrode potential and additional byproduct, the sulfuric acid, can provide economically affordable hydrogen. In this study, the once-through hybrid sulfur process for hydrogen production was proposed and the process was optimized considering energy consumption in electrolysis and sulfuric acid concentration. Economic feasibility of the proposed process was also discussed. Based on currently available experimental data for the electrode

Biological hydrogen production by moderately thermophilic anaerobic bacteria

International Nuclear Information System (INIS)

HP Goorissen; AJM Stams

2006-01-01

This study focuses on the biological production of hydrogen at moderate temperatures (65-75 C) by anaerobic bacteria. A survey was made to select the best (moderate) thermophiles for hydrogen production from cellulolytic biomass. From this survey we selected Caldicellulosiruptor saccharolyticus (a gram-positive bacterium) and Thermotoga elfii (a gram-negative bacterium) as potential candidates for biological hydrogen production on mixtures of C 5 -C 6 sugars. Xylose and glucose were used as model substrates to describe growth and hydrogen production from hydrolyzed biomass. Mixed substrate utilization in batch cultures revealed differences in the sequence of substrate consumption and in catabolites repression of the two microorganisms. The regulatory mechanisms of catabolites repression in these microorganisms are not known yet. (authors)

Hydrogen production by radiation

International Nuclear Information System (INIS)

Jung, Jin Ho; Lee, M. J.; Jin, J. H.; Park, K. B.; Cho, Y. H.; Jeong, H. S.; Chung, H. H.; Jeong, Y. S.; Ahn, S. S.

2001-04-01

In this work, various kinds of catalysts including a nanosize TiO2 (nTiO 2 ) were examined in respect to the efficiency of H2 production by gamma rays.The different activity of catalysts was characterized by X-ray powder diffraction (XRD) and electron paramagnetic resonance (EPR). A combination of EPR and spin-trapping method was also used to detect unstable radicals such as hydroxyl radicals and hydrogen atoms to investigate the effect of catalysts and additives on the efficiency of H2 production. A nanosize TiO 2 (nTiO 2 ) catalyst that showed an excellent activity in the production of H2 from water by gamma rays were examined in respect to the efficiency of H2 production with concomitant treatment of metal-EDTA complexes that are main wastes of chemical cleaning wastewater. As a result, among the catalysts examined in this work, a nanosize TiO2 (nTiO 2 ) showed the most efficient H2 production and the efficiency increased upon reapplication. This catalyst was also successfully used to produce H2 with concomitant treatment of metal-EDTA complexes

Resource Assessment for Hydrogen Production: Hydrogen Production Potential from Fossil and Renewable Energy Resources

Energy Technology Data Exchange (ETDEWEB)

Melaina, M. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Penev, M. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Heimiller, D. [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2013-09-01

This study examines the energy resources required to produce 4-10 million metric tonnes of domestic, low-carbon hydrogen in order to fuel approximately 20-50 million fuel cell electric vehicles. These projected energy resource requirements are compared to current consumption levels, projected 2040 business as usual consumptions levels, and projected 2040 consumption levels within a carbonconstrained future for the following energy resources: coal (assuming carbon capture and storage), natural gas, nuclear (uranium), biomass, wind (on- and offshore), and solar (photovoltaics and concentrating solar power). The analysis framework builds upon previous analysis results estimating hydrogen production potentials and drawing comparisons with economy-wide resource production projections

Cobalt Ferrite Nanocrystallites for Sustainable Hydrogen Production Application

Directory of Open Access Journals (Sweden)

Rajendra S. Gaikwad

2011-01-01

Full Text Available Cobalt ferrite, CoFe2O4, nanocrystalline films were deposited using electrostatic spray method and explored in sustainable hydrogen production application. Reflection planes in X-ray diffraction pattern confirm CoFe2O4 phase. The surface scanning microscopy photoimages reveal an agglomeration of closely-packed CoFe2O4 nanoflakes. Concentrated solar-panel, a two-step water splitting process, measurement technique was preferred for measuring the hydrogen generation rate. For about 5 hr sustainable, 440 mL/hr, hydrogen production activity was achieved, confirming the efficient use of cobalt ferrite nanocrystallites film in hydrogen production application.

Long-term effect of inoculum pretreatment on fermentative hydrogen production by repeated batch cultivations: homoacetogenesis and methanogenesis as competitors to hydrogen production

DEFF Research Database (Denmark)

Luo, Gang; Karakashev, Dimitar Borisov; Xie, Li

2011-01-01

Long-term effects of inoculum pretreatments(heat, acid, loading-shock) on hydrogen production from glucose under different temperatures (378C, 558C) and initial pH (7 and 5.5) were studied by repeated batch cultivations. Results obtained showed that it was necessary to investigate the long......-term effect of inoculum pretreatment on hydrogen production since pretreatments may just temporarily inhibit the hydrogen consuming processes. After long-term cultivation, pretreated inocula did not enhance hydrogen production compared to untreated inocula under mesophilic conditions (initial pH 7 and pH 5.......5) and thermophilic conditions (initial pH 7). However, pretreatment could inhibit lactate production and lead to higher hydrogen yield under thermophilic conditions at initial pH 5.5. The results further demonstrated that inoculum pretreatment could not permanently inhibit either methanogenesis or homoacetogenesis...

Regulation of hydrogen production by Enterobacter aerogenes by external NADH and NAD{sup +}

Energy Technology Data Exchange (ETDEWEB)

Zhang, Chong; Ma, Kun; Xing, Xin-Hui [Department of Chemical Engineering, Tsinghua University, Beijing 100084 (China)

2009-02-15

Experiments involving the addition of external nicotinamide adenine dinucleotide, reduced form (NADH) or nicotinamide adenine dinucleotide (NAD{sup +}) have been designed to examine how the hydrogen in Enterobacter aerogenes is liberated by NADH or NAD{sup +}. The addition of external NADH or NAD{sup +} was found to regulate hydrogen production by E. aerogenes in resting cells, batch cultures, and chemostat cultures. Particularly in chemostat cultivation, with the external addition of NADH, hydrogen production via the NADH pathway was decreased, while that via the formate pathway was increased; in the end, the overall hydrogen p was decreased. The addition of NAD{sup +}, on the other hand, gave the opposite results. The membrane-bound hydrogenase was found to play a central role in regulating hydrogen production. The occurrence of NADH oxidation (NAD{sup +} reduction) on the cell membrane resulted in an electron flow across the membrane; this changed the oxidation state and metabolic pattern of the cells, which eventually affected the hydrogen evolution. (author)

Hydrogen production in a PWR during LOCA

International Nuclear Information System (INIS)

Cassette, P.

1984-01-01

Hydrogen generation during a PWR LOCA has been estimated for design basis accident and for two more severe hypothetical accidents. Hydrogen production during design basis accident is a rather slow mechanism, allowing in the worst case, 15 days to connect a hydrogen recombining unit to the containment atmosphere monitoring system. Hydrogen generated by steam oxidation during more severe hypothetical accidents was found limited by steam availability and fuel melting phenomena. Uncertainty is, however, still remaining on corium-zirconium-steam interaction. In the worst case, calculations lead to the production of 500 kg of hydrogen, thus leading to a volume concentration of 15% in containment atmosphere, assuming homogeneous hydrogen distribution within the reactor building. This concentration is within flammability limits but not within detonation limits. However, hydrogen detonation due to local hydrogen accumulation cannot be discarded. A major uncertainty subsisting on hydrogen hazard is hydrogen distribution during the first hours of the accident. This point determines the effects and consequences of local detonation or deflagration which could possibly be harmful to safeguard systems, or induce missile generation in the reactor building. As electrical supply failures are identified as an important contributor to severe accident risk, corrective actions have been taken in France to improve their reliability, including the installation of a gas turbine on each site to supplement the existing sources. These actions are thus contributing to hydrogen hazard reduction

Technology selection for hydrogen production using nuclear energy

International Nuclear Information System (INIS)

Siti Alimah; Erlan Dewita

2008-01-01

The NPP can either be used to produce electricity, or as heat source for non-electric applications (cogeneration). High Temperature Reactor (HTR) with high outlet coolant temperature around 900~1000 o C, is a reactor type potential for cogeneration purposes such as hydrogen production and other chemical industry processes that need high heat. Considering the national energy policy that a balanced arrangement of renewable and unrenewable natural resources has to be made to keep environmental conservation for the sake of society prosperity in the future, hydrogen gas production using nuclear heat is an appropriate choice. Hydrogen gas is a new energy which is environmentally friendly that it is a prospecting alternative energy source in the future. Within the study, a comparison of three processes of hydrogen gas production covering electrolysis, steam reforming and sulfur-iodine cycle, have been conducted. The parameters that considered are the production cost, capital cost and energy cost, technological status, the independence of fossil fuel, the environmental friendly aspect, as well as the efficiency and the independence of corrosion-resistance material. The study result showed that hydrogen gas production by steam reforming is a better process compared to electrolysis and sulfur-iodine process. Therefore, steam reforming process can be a good choice for hydrogen gas production using nuclear energy in Indonesia. (author)

Uncertainty propagation in modeling of plasma-assisted hydrogen production from biogas

Science.gov (United States)

Zaherisarabi, Shadi; Venkattraman, Ayyaswamy

2016-10-01

With the growing concern of global warming and the resulting emphasis on decreasing greenhouse gas emissions, there is an ever-increasing need to utilize energy-production strategies that can decrease the burning of fossil fuels. In this context, hydrogen remains an attractive clean-energy fuel that can be oxidized to produce water as a by-product. In spite of being an abundant species, hydrogen is seldom found in a form that is directly usable for energy-production. While steam reforming of methane is one popular technique for hydrogen production, plasma-assisted conversion of biogas (carbon dioxide + methane) to hydrogen is an attractive alternative. Apart from producing hydrogen, the other advantage of using biogas as raw material is the fact that two potent greenhouse gases are consumed. In this regard, modeling is an important tool to understand and optimize plasma-assisted conversion of biogas. The primary goal of this work is to perform a comprehensive statistical study that quantifies the influence of uncertain rate constants thereby determining the key reaction pathways. A 0-D chemical kinetics solver in the OpenFOAM suite is used to perform a series of simulations to propagate the uncertainty in rate constants and the resulting mean and standard deviation of outcomes.

Co-fermentation of sewage sludge with ryegrass for enhancing hydrogen production: Performance evaluation and kinetic analysis.

Science.gov (United States)

Yang, Guang; Wang, Jianlong

2017-11-01

The low C/N ratio and low carbohydrate content of sewage sludge limit its application for fermentative hydrogen production. In this study, perennial ryegrass was added as the co-substrate into sludge hydrogen fermentation with different mixing ratios for enhancing hydrogen production. The results showed that the highest hydrogen yield of 60mL/g-volatile solids (VS) added was achieved when sludge/perennial ryegrass ratio was 30:70, which was 5 times higher than that from sole sludge. The highest VS removal of 21.8% was also achieved when sludge/perennial ryegrass ratio was 30:70, whereas VS removal from sole sludge was only 0.7%. Meanwhile, the co-fermentation system simultaneously improved hydrogen production efficiency and organics utilization of ryegrass. Kinetic analysis showed that the Cone model fitted hydrogen evolution better than the modified Gompertz model. Furthermore, hydrogen yield and VS removal increased with the increase of dehydrogenase activity. Copyright © 2017 Elsevier Ltd. All rights reserved.

Batch dark fermentation from enzymatic hydrolyzed food waste for hydrogen production.

Science.gov (United States)

Han, Wei; Ye, Min; Zhu, Ai Jun; Zhao, Hong Ting; Li, Yong Feng

2015-09-01

A combination bioprocess of solid-state fermentation (SSF) and dark fermentative hydrogen production from food waste was developed. Aspergillus awamori and Aspergillus oryzae were utilized in SSF from food waste to generate glucoamylase and protease which were used to hydrolyze the food waste suspension to get the nutrients-rich (glucose and free amino nitrogen (FAN)) hydrolysate. Both glucose and FAN increased with increasing of food waste mass ratio from 4% to 10% (w/v) and the highest glucose (36.9 g/L) and FAN (361.3mg/L) were observed at food waste mass ratio of 10%. The food waste hydrolysates were then used as the feedstock for dark fermentative hydrogen production by heat pretreated sludge. The best hydrogen yield of 39.14 ml H2/g food waste (219.91 ml H2/VSadded) was achieved at food waste mass ratio of 4%. The proposed combination bioprocess could effectively accelerate the hydrolysis rate, improve raw material utilization and enhance hydrogen yield. Copyright © 2015 Elsevier Ltd. All rights reserved.

Hydrogen production under salt stress conditions by a freshwater Rhodopseudomonas palustris strain.

Science.gov (United States)

Adessi, Alessandra; Concato, Margherita; Sanchini, Andrea; Rossi, Federico; De Philippis, Roberto

2016-03-01

Hydrogen represents a possible alternative energy carrier to face the growing request for energy and the shortage of fossil fuels. Photofermentation for the production of H2 constitutes a promising way for integrating the production of energy with waste treatments. Many wastes are characterized by high salinity, and polluted seawater can as well be considered as a substrate. Moreover, the application of seawater for bacterial culturing is considered cost-effective. The aims of this study were to assess the capability of the metabolically versatile freshwater Rhodopseudomonas palustris 42OL of producing hydrogen on salt-containing substrates and to investigate its salt stress response strategy, never described before. R. palustris 42OL was able to produce hydrogen in media containing up to 3 % added salt concentration and to grow in media containing up to 4.5 % salinity without the addition of exogenous osmoprotectants. While the hydrogen production performances in absence of sea salts were higher than in their presence, there was no significant difference in performances between 1 and 2 % of added sea salts. Nitrogenase expression levels indicated that the enzyme was not directly inhibited during salt stress, but a regulation of its expression may have occurred in response to salt concentration increase. During cell growth and hydrogen production in the presence of salts, trehalose was accumulated as a compatible solute; it protected the enzymatic functionality against salt stress, thus allowing hydrogen production. The possibility of producing hydrogen on salt-containing substrates widens the range of wastes that can be efficiently used in production processes.

Advances in hydrogen production by thermochemical water decomposition: A review

International Nuclear Information System (INIS)

Rosen, Marc A.

2010-01-01

Hydrogen demand as an energy currency is anticipated to rise significantly in the future, with the emergence of a hydrogen economy. Hydrogen production is a key component of a hydrogen economy. Several production processes are commercially available, while others are under development including thermochemical water decomposition, which has numerous advantages over other hydrogen production processes. Recent advances in hydrogen production by thermochemical water decomposition are reviewed here. Hydrogen production from non-fossil energy sources such as nuclear and solar is emphasized, as are efforts to lower the temperatures required in thermochemical cycles so as to expand the range of potential heat supplies. Limiting efficiencies are explained and the need to apply exergy analysis is illustrated. The copper-chlorine thermochemical cycle is considered as a case study. It is concluded that developments of improved processes for hydrogen production via thermochemical water decomposition are likely to continue, thermochemical hydrogen production using such non-fossil energy will likely become commercial, and improved efficiencies are expected to be obtained with advanced methodologies like exergy analysis. Although numerous advances have been made on sulphur-iodine cycles, the copper-chlorine cycle has significant potential due to its requirement for process heat at lower temperatures than most other thermochemical processes.

Evaluation of hydrogen production from CO2 corrosion of steel drums in SFR, Part 2

International Nuclear Information System (INIS)

Dugstad, A.; Videm, K.

1987-06-01

An experimental program has been carried out for the investigation of the hydrogen formation due to corrosion of steel by water containing CO 2 produced by microbiologic decomposition of paper in waste drums. The hydrogen production will be limited by a limited rate of CO 2 production, as CO 2 is consumed by corrosive reactions producing carbonate containing corrosion products. Experiments indicated that also iron oxide and hydroxides were formed together with FeCO 3 at low CO 2 partial pressures but at a rate which leads to a rather slow increase in hydrogen production. Hydrogen evaluation has been overestimated in previous reports on this subject. (authors)

Production of bioplastics and hydrogen gas by photosynthetic microorganisms

Science.gov (United States)

Yasuo, Asada; Masato, Miyake; Jun, Miyake

1998-03-01

Our efforts have been aimed at the technological basis of photosynthetic-microbial production of materials and an energy carrier. We report here accumulation of poly-(3-hydroxybutyrate) (PHB), a raw material of biodegradable plastics and for production of hydrogen gas, and a renewable energy carrier by photosynthetic microorganisms (tentatively defined as cyanobacteria plus photosynthetic bateria, in this report). A thermophilic cyanobacterium, Synechococcus sp. MA19 that accumulates PHB at more than 20% of cell dry wt under nitrogen-starved conditions was isolated and microbiologically identified. The mechanism of PHB accumulation was studied. A mesophilic Synechococcus PCC7942 was transformed with the genes encoding PHB-synthesizing enzymes from Alcaligenes eutrophus. The transformant accumulated PHB under nitrogen-starved conditions. The optimal conditions for PHB accumulation by a photosynthetic bacterium grown on acetate were studied. Hydrogen production by photosynthetic microorganisms was studied. Cyanobacteria can produce hydrogen gas by nitrogenase or hydrogenase. Hydrogen production mediated by native hydrogenase in cyanobacteria was revealed to be in the dark anaerobic degradation of intracellular glycogen. A new system for light-dependent hydrogen production was targeted. In vitro and in vivo coupling of cyanobacterial ferredoxin with a heterologous hydrogenase was shown to produce hydrogen under light conditions. A trial for genetic trasformation of Synechococcus PCC7942 with the hydrogenase gene from Clostridium pasteurianum is going on. The strong hydrogen producers among photosynthetic bacteria were isolated and characterized. Co-culture of Rhodobacter and Clostriumdium was applied to produce hydrogen from glucose. Conversely in the case of cyanobacteria, genetic regulation of photosynthetic proteins was intended to improve conversion efficiency in hydrogen production by the photosynthetic bacterium, Rhodobacter sphaeroides RV. A mutant acquired by

Hydrogen production by high-temperature gas-cooled reactor. Conceptual design of advanced process heat exchangers of the HTTR-IS hydrogen production system

International Nuclear Information System (INIS)

Sakaba, Nariaki; Ohashi, Hirofumi; Sato, Hiroyuki; Hara, Teruo; Kato, Ryoma; Kunitomi, Kazuhiko

2008-01-01

Nuclear hydrogen production is necessary in an anticipated hydrogen society that demands a massive quantity of hydrogen without economic disadvantage. Japan Atomic Energy Agency (JAEA) has launched the conceptual design study of a hydrogen production system with a near-term plan to connect it to Japan's first high-temperature gas-cooled reactor HTTR. The candidate hydrogen production system is based on the thermochemical water-splitting iodine sulphur (IS) process.The heat of 10 MWth at approximately 900degC, which can be provided by the secondary helium from the intermediate heat exchanger of the HTTR, is the energy input to the hydrogen production system. In this paper, we describe the recent progresses made in the conceptual design of advanced process heat exchangers of the HTTR-IS hydrogen production system. A new concept of sulphuric acid decomposer is proposed. This involves the integration of three separate functions of sulphuric acid decomposer, sulphur trioxide decomposer, and process heat exchanger. A new mixer-settler type of Bunsen reactor is also designed. This integrates three separate functions of Bunsen reactor, phase separator, and pump. The new concepts are expected to result in improved economics through construction and operation cost reductions because the number of process equipment and complicated connections between the equipment has been substantially reduced. (author)

South Africa's nuclear hydrogen production development programme

International Nuclear Information System (INIS)

Van Ravenswaay, J.P.; Van Niekerk, F.; Kriek, R.J.; Blom, E.; Krieg, H.M.; Van Niekerk, W.M.K.; Van der Merwe, F.; Vosloo, H.C.M.

2010-01-01

In May 2007 the South African Cabinet approved a National Hydrogen and Fuel Cell Technologies R and D and Innovation Strategy. The strategy will focus on research, development and innovation for: i) wealth creation through high value-added manufacturing and developing platinum group metals catalysis; ii) building on the existing knowledge in high temperature gas-cooled reactors (HTGR) and coal gasification Fischer-Tropsch technology, to develop local cost-competitive hydrogen production solutions; iii) to promote equity and inclusion in the economic benefits from South Africa's natural resource base. As part of the roll-out strategy, the South African Department of Science and Technology (DST) created three Competence Centres (CC), including a Hydrogen Infrastructure Competence Centre hosted by the North-West University (NWU) and the Council for Scientific and Industrial Research (CSIR). The Hydrogen Infrastructure CC is tasked with developing hydrogen production, storage, distribution as well as codes and standards programmes within the framework of the DST strategic objectives to ensure strategic national innovation over the next fifteen years. One of the focus areas of the Hydrogen Infrastructure CC will be on large scale CO 2 free hydrogen production through thermochemical water-splitting using nuclear heat from a suitable heat source such as a HTGR and the subsequent use of the hydrogen in applications such as the coal-to-liquid process and the steel industry. This paper will report on the status of the programme for thermochemical water-splitting as well as the associated projects for component and technology development envisaged in the Hydrogen Infrastructure CC. The paper will further elaborate on current and future collaboration opportunities as well as expected outputs and deliverables. (authors)

40 CFR 415.330 - Applicability; description of the carbon monoxide and by-product hydrogen production subcategory.

Science.gov (United States)

2010-07-01

... carbon monoxide and by-product hydrogen production subcategory. 415.330 Section 415.330 Protection of... MANUFACTURING POINT SOURCE CATEGORY Carbon Monoxide and By-Product Hydrogen Production Subcategory § 415.330 Applicability; description of the carbon monoxide and by-product hydrogen production subcategory. The provisions...

On-Board Hydrogen Gas Production System For Stirling Engines

Science.gov (United States)

Johansson, Lennart N.

2004-06-29

A hydrogen production system for use in connection with Stirling engines. The production system generates hydrogen working gas and periodically supplies it to the Stirling engine as its working fluid in instances where loss of such working fluid occurs through usage through operation of the associated Stirling engine. The hydrogen gas may be generated by various techniques including electrolysis and stored by various means including the use of a metal hydride absorbing material. By controlling the temperature of the absorbing material, the stored hydrogen gas may be provided to the Stirling engine as needed. A hydrogen production system for use in connection with Stirling engines. The production system generates hydrogen working gas and periodically supplies it to the Stirling engine as its working fluid in instances where loss of such working fluid occurs through usage through operation of the associated Stirling engine. The hydrogen gas may be generated by various techniques including electrolysis and stored by various means including the use of a metal hydride absorbing material. By controlling the temperature of the absorbing material, the stored hydrogen gas may be provided to the Stirling engine as needed.

Hydrogen production as a promising nuclear energy application

International Nuclear Information System (INIS)

Vanek, V.

2003-01-01

Hydrogen production from nuclear is a field of application which eventually can outweigh power production by nuclear power plants. There are two feasible routes of hydrogen production. The one uses heat to obtain hydrogen from natural gas through steam reforming of methane. This is an highly energy-consuming process requiring temperatures up to 900 deg C and producing carbon dioxide as a by-product. The other method includes direct thermochemical processes to obtain hydrogen, using sulfuric acid for instance. Sulfuric acid is decomposed thermally by the reaction: H 2 SO 4 -> H 2 O = SO 2 + (1/2) O 2 , followed by the processes I 2 + SO 2 + 2H O -> 2HI + H 2 SO 4 and 2HI -> H 2 + I 2 . The use of nuclear for this purpose is currently examined in Japan and in the US. (P.A.)

Hydrogen Sulfide Increases Nitric Oxide Production and Subsequent S-Nitrosylation in Endothelial Cells

Directory of Open Access Journals (Sweden)

Ping-Ho Chen

2014-01-01

Full Text Available Hydrogen sulfide (H2S and nitric oxide (NO, two endogenous gaseous molecules in endothelial cells, got increased attention with respect to their protective roles in the cardiovascular system. However, the details of the signaling pathways between H2S and NO in endothelia cells remain unclear. In this study, a treatment with NaHS profoundly increased the expression and the activity of endothelial nitric oxide synthase. Elevated gaseous NO levels were observed by a novel and specific fluorescent probe, 5-amino-2-(6-hydroxy-3-oxo-3H-xanthen-9-ylbenzoic acid methyl ester (FA-OMe, and quantified by flow cytometry. Further study indicated an increase of upstream regulator for eNOS activation, AMP-activated protein kinase (AMPK, and protein kinase B (Akt. By using a biotin switch, the level of NO-mediated protein S-nitrosylation was also enhanced. However, with the addition of the NO donor, NOC-18, the expressions of cystathionine-γ-lyase, cystathionine-β-synthase, and 3-mercaptopyruvate sulfurtransferase were not changed. The level of H2S was also monitored by a new designed fluorescent probe, 4-nitro-7-thiocyanatobenz-2-oxa-1,3-diazole (NBD-SCN with high specificity. Therefore, NO did not reciprocally increase the expression of H2S-generating enzymes and the H2S level. The present study provides an integrated insight of cellular responses to H2S and NO from protein expression to gaseous molecule generation, which indicates the upstream role of H2S in modulating NO production and protein S-nitrosylation.

Increased Production of Hydrogen Peroxide by Lactobacillus delbrueckii subsp. bulgaricus upon Aeration: Involvement of an NADH Oxidase in Oxidative Stress

Science.gov (United States)

Marty-Teysset, C.; de la Torre, F.; Garel, J.-R.

2000-01-01

The growth of Lactobacillus delbrueckii subsp. bulgaricus (L. delbrueckii subsp. bulgaricus) on lactose was altered upon aerating the cultures by agitation. Aeration caused the bacteria to enter early into stationary phase, thus reducing markedly the biomass production but without modifying the maximum growth rate. The early entry into stationary phase of aerated cultures was probably related to the accumulation of hydrogen peroxide in the medium. Indeed, the concentration of hydrogen peroxide in aerated cultures was two to three times higher than in unaerated ones. Also, a similar shift from exponential to stationary phase could be induced in unaerated cultures by adding increasing concentrations of hydrogen peroxide. A significant fraction of the hydrogen peroxide produced by L. delbrueckii subsp. bulgaricus originated from the reduction of molecular oxygen by NADH catalyzed by an NADH:H2O2 oxidase. The specific activity of this NADH oxidase was the same in aerated and unaerated cultures, suggesting that the amount of this enzyme was not directly regulated by oxygen. Aeration did not change the homolactic character of lactose fermentation by L. delbrueckii subsp. bulgaricus and most of the NADH was reoxidized by lactate dehydrogenase with pyruvate. This indicated that NADH oxidase had no (or a very small) energetic role and could be involved in eliminating oxygen. PMID:10618234

Lichen symbiosis: nature's high yielding machines for induced hydrogen production.

Directory of Open Access Journals (Sweden)

Aikaterini Papazi

Full Text Available Hydrogen is a promising future energy source. Although the ability of green algae to produce hydrogen has long been recognized (since 1939 and several biotechnological applications have been attempted, the greatest obstacle, being the O2-sensitivity of the hydrogenase enzyme, has not yet been overcome. In the present contribution, 75 years after the first report on algal hydrogen production, taking advantage of a natural mechanism of oxygen balance, we demonstrate high hydrogen yields by lichens. Lichens have been selected as the ideal organisms in nature for hydrogen production, since they consist of a mycobiont and a photobiont in symbiosis. It has been hypothesized that the mycobiont's and photobiont's consumption of oxygen (increase of COX and AOX proteins of mitochondrial respiratory pathways and PTOX protein of chrolorespiration establishes the required anoxic conditions for the activation of the phycobiont's hydrogenase in a closed system. Our results clearly supported the above hypothesis, showing that lichens have the ability to activate appropriate bioenergetic pathways depending on the specific incubation conditions. Under light conditions, they successfully use the PSII-dependent and the PSII-independent pathways (decrease of D1 protein and parallel increase of PSaA protein to transfer electrons to hydrogenase, while under dark conditions, lichens use the PFOR enzyme and the dark fermentative pathway to supply electrons to hydrogenase. These advantages of lichen symbiosis in combination with their ability to survive in extreme environments (while in a dry state constitute them as unique and valuable hydrogen producing natural factories and pave the way for future biotechnological applications.

Lichen Symbiosis: Nature's High Yielding Machines for Induced Hydrogen Production

Science.gov (United States)

Papazi, Aikaterini; Kastanaki, Elizabeth; Pirintsos, Stergios; Kotzabasis, Kiriakos

2015-01-01

Hydrogen is a promising future energy source. Although the ability of green algae to produce hydrogen has long been recognized (since 1939) and several biotechnological applications have been attempted, the greatest obstacle, being the O2-sensitivity of the hydrogenase enzyme, has not yet been overcome. In the present contribution, 75 years after the first report on algal hydrogen production, taking advantage of a natural mechanism of oxygen balance, we demonstrate high hydrogen yields by lichens. Lichens have been selected as the ideal organisms in nature for hydrogen production, since they consist of a mycobiont and a photobiont in symbiosis. It has been hypothesized that the mycobiont’s and photobiont’s consumption of oxygen (increase of COX and AOX proteins of mitochondrial respiratory pathways and PTOX protein of chrolorespiration) establishes the required anoxic conditions for the activation of the phycobiont’s hydrogenase in a closed system. Our results clearly supported the above hypothesis, showing that lichens have the ability to activate appropriate bioenergetic pathways depending on the specific incubation conditions. Under light conditions, they successfully use the PSII-dependent and the PSII-independent pathways (decrease of D1 protein and parallel increase of PSaA protein) to transfer electrons to hydrogenase, while under dark conditions, lichens use the PFOR enzyme and the dark fermentative pathway to supply electrons to hydrogenase. These advantages of lichen symbiosis in combination with their ability to survive in extreme environments (while in a dry state) constitute them as unique and valuable hydrogen producing natural factories and pave the way for future biotechnological applications. PMID:25826211

IEA hydrogen agreement, task 15: photobiological hydrogen production - an international collaboration

International Nuclear Information System (INIS)

Lindblad, P.; Asada, Y.; Benemann, J.; Hallenbeck, P.; Melis, A.; Miyake, J.; Seibert, M.; Skulberg, O.

2000-01-01

Biological hydrogen production, the production of H 2 by microorganisms, has been an active field of basic and applied research for many years. Realization of practical processes for photobiological hydrogen production from water using solar energy would result in a major, novel source of sustainable and renewable energy, without greenhouse gas emissions or environmental pollution. However, development of such processes requires significant scientific and technological advances, and long-term basic and applied R and D. This International Energy Agency (lEA) Task covers research areas and needs at the interface of basic and applied R and D which are of mutual interest to the countries and researchers participating in the lEA Hydrogen Agreement. The overall objective is to sufficiently advance the basic and early-stage applied science in this area of research over the next five years to allow an evaluation of the potential of such a technology to be developed as a practical renewable energy source for the 21st Century. (author)

Photobiological hydrogen production : photochemical efficiency and bioreactor design

NARCIS (Netherlands)

Akkerman, I.; Janssen, M.; Rocha, J.; Wijffels, R.H.

2002-01-01

Biological production of hydrogen can be carried out by photoautotrophic or photoheterotrophic organisms. Here, the photosystems of both processes are described. The main drawback of the photoautotrophic hydrogen production process is oxygen inhibition. The few efficiencies reported on the

Mesophilic and thermophilic alkaline fermentation of waste activated sludge for hydrogen production: Focusing on homoacetogenesis

DEFF Research Database (Denmark)

Wan, Jingjing; Jing, Yuhang; Zhang, Shicheng

2016-01-01

The present study compared the mesophilic and thermophilic alkaline fermentation of waste activated sludge (WAS) for hydrogen production with focus on homoacetogenesis, which mediated the consumption of H2 and CO2 for acetate production. Batch experiments showed that hydrogen yield of WAS increased...

Production of hydrogen by thermocatalytic cracking of natural gas

Energy Technology Data Exchange (ETDEWEB)

Muradov, N. [Florida Solar Energy Center, Cocoa, FL (United States)

1996-10-01

The conventional methods of hydrogen production from natural gas (for example, steam reforming and partial oxidation) are complex, multi-step processes that produce large quantities of CO{sub 2}. The main goal of this project is to develop a technologically simple process for hydrogen production from natural gas (NG) and other hydrocarbon fuels via single-step decomposition of hydrocarbons. This approach eliminates or significantly reduces CO{sub 2} emission. Carbon is a valuable by-product of this process, whereas conventional methods of hydrogen production from NG produce no useful by-products. This approach is based on the use of special catalysts that reduce the maximum temperature of the process from 1400-1500{degrees}C (thermal non-catalytic decomposition of methane) to 500-900{degrees}C. Transition metal based catalysts and various forms of carbon are among the candidate catalysts for the process. This approach can advantageously be used for the development of compact NG reformers for on-site production of hydrogen-methane blends at refueling stations and, also, for the production of hydrogen-rich gas for fuel cell applications. The author extended the search for active methane decomposition catalysts to various modifications of Ni-, Fe-, Mo- and Co-based catalysts. Variation in the operational parameters makes it possible to produce H{sub 2}-CH{sub 4} blends with a wide range of hydrogen concentrations that vary from 15 to 98% by volume. The author found that Ni-based catalysts are more effective at temperatures below 750{degrees}C, whereas Fe-based catalysts are effective at temperatures above 800{degrees}C for the production of hydrogen with purity of 95% v. or higher. The catalytic pyrolysis of liquid hydrocarbons (pentane, gasoline) over Fe-based catalyst was conducted. The author observed the production of a hydrogen-rich gas (hydrogen concentration up to 97% by volume) at a rate of approximately 1L/min.mL of hydrocarbon fuel.

Enhancement of bioenergy production from organic wastes by two-stage anaerobic hydrogen and methane production process

DEFF Research Database (Denmark)

Luo, Gang; Xie, Li; Zhou, Qi

2011-01-01

The present study investigated a two-stage anaerobic hydrogen and methane process for increasing bioenergy production from organic wastes. A two-stage process with hydraulic retention time (HRT) 3d for hydrogen reactor and 12d for methane reactor, obtained 11% higher energy compared to a single......:12 to 1:14, 6.7%, more energy could be obtained. Microbial community analysis indicated that the dominant bacterial species were different in the hydrogen reactors (Thermoanaerobacterium thermosaccharolyticum-like species) and methane reactors (Clostridium thermocellum-like species). The changes...

Nuclear hydrogen: An assessment of product flexibility and market viability

International Nuclear Information System (INIS)

Botterud, Audun; Yildiz, Bilge; Conzelmann, Guenter; Petri, Mark C.

2008-01-01

Nuclear energy has the potential to play an important role in the future energy system as a large-scale source of hydrogen without greenhouse gas emissions. Thus far, economic studies of nuclear hydrogen tend to focus on the levelized cost of hydrogen without accounting for the risks and uncertainties that potential investors would face. We present a financial model based on real options theory to assess the profitability of different nuclear hydrogen production technologies in evolving electricity and hydrogen markets. The model uses Monte Carlo simulations to represent uncertainty in future hydrogen and electricity prices. It computes the expected value and the distribution of discounted profits from nuclear hydrogen production plants. Moreover, the model quantifies the value of the option to switch between hydrogen and electricity production, depending on what is more profitable to sell. We use the model to analyze the market viability of four potential nuclear hydrogen technologies and conclude that flexibility in output product is likely to add significant economic value for an investor in nuclear hydrogen. This should be taken into account in the development phase of nuclear hydrogen technologies

Bio-hydrogen production from renewable organic wastes

Energy Technology Data Exchange (ETDEWEB)

Shihwu Sung

2004-04-30

Methane fermentation has been in practice over a century for the stabilization of high strength organic waste/wastewater. Although methanogenesis is a well established process and methane--the end-product of methanogenesis is a useful energy source; it is a low value end product with relatively less energy content (about 56 kJ energy/g CH{sub 4}). Besides, methane and its combustion by-product are powerful greenhouse gases, and responsible for global climate change. So there is a pressing need to explore alternative environmental technologies that not only stabilize the waste/wastewater but also generate benign high value end products. From this perspective, anaerobic bioconversion of organic wastes to hydrogen gas is an attractive option that achieves both goals. From energy security stand point, generation of hydrogen energy from renewable organic waste/wastewater could substitute non-renewable fossil fuels, over two-third of which is imported from politically unstable countries. Thus, biological hydrogen production from renewable organic waste through dark fermentation represents a critically important area of bioenergy production. This study evaluated both process engineering and microbial physiology of biohydrogen production.

Concepts for Large Scale Hydrogen Production

OpenAIRE

Jakobsen, Daniel; Åtland, Vegar

2016-01-01

The objective of this thesis is to perform a techno-economic analysis of large-scale, carbon-lean hydrogen production in Norway, in order to evaluate various production methods and estimate a breakeven price level. Norway possesses vast energy resources and the export of oil and gas is vital to the country s economy. The results of this thesis indicate that hydrogen represents a viable, carbon-lean opportunity to utilize these resources, which can prove key in the future of Norwegian energy e...

Thermal energy distribution analysis for hydrogen production in RGTT200K conceptual design

International Nuclear Information System (INIS)

Tumpal Pandiangan; Ign Djoko Irianto

2011-01-01

RGTT200K is a high temperature gas-cooled reactor (HTGR) which conceptually designed for power generation, hydrogen production and desalination. Hydrogen production process in this design uses thermochemical method of Iodine-Sulphur. To increase the thermal conversion efficiency in hydrogen production installations, it needs to design a thermal energy distribution and temperature associated with the process of thermo-chemical processes in the method of Iodine-Sulphur. In this method there are 7 kinds of processes: (i) H 2 SO4 decomposition reaction (ii) treatment of vaporization (iii) treatment of pre vaporizer (iv) treatment of flash 4 (v) treatment of decomposition of HI (vi) treatment of the flash 1-3 and (vii) Bunsen reaction. To regulate the distribution of energy and temperature appropriate to the needs of each process used 3 pieces of heat exchanger (HE). Calculation of energy distribution through the distribution of helium gas flow has been done with Scilab application programs, so that can know the distribution of thermal energy for production of 1 mole of hydrogen. From this model, it can calculate the thermal energy requirement for production of hydrogen at the desired capacity. In the conceptual design of RGTT200K, helium discharge has been designed by 20 kg/s, so that an efficient hydrogen production capacity needed to produce 15347.8 for 21.74 mole of H 2 . (author)

Thermodynamic evaluation of hydrogen production via bioethanol steam reforming

Energy Technology Data Exchange (ETDEWEB)

Tasnadi-Asztalos, Zsolt; Cormos, Ana-Maria; Imre-Lucaci, Árpád; Cormos, Călin C. [Babes-Bolyai University, Faculty of Chemistry and Chemical Engineering, Arany Janos 11, RO-400028, Cluj-Napoca (Romania)

2013-11-13

In this article, a thermodynamic analysis for bioethanol steam reforming for hydrogen production is presented. Bioethanol is a newly proposed renewable energy carrier mainly produced from biomass fermentation. Reforming of bioethanol provides a promising method for hydrogen production from renewable resources. Steam reforming of ethanol (SRE) takes place under the action of a metal catalyst capable of breaking C-C bonds into smaller molecules. A large domain for the water/bioethanol molar ratio as well as the temperature and average pressure has been used in the present work. The interval of investigated temperature was 100-800°C, the pressure was in the range of 1-10 bar and the molar ratio was between 3-25. The variations of gaseous species concentration e.g. H{sub 2}, CO, CO{sub 2}, CH{sub 4} were analyzed. The concentrations of the main products (H{sub 2} and CO) at lower temperature are smaller than the ones at higher temperature due to by-products formation (methane, carbon dioxide, acetylene etc.). The concentration of H2 obtained in the process using high molar ratio (>20) is higher than the one at small molar ratio (near stoichiometric). When the pressure is increased the hydrogen concentration decreases. The results were compared with literature data for validation purposes.

Photoelectrochemical Hydrogen Production Using New Combinatorial Chemistry Derived Materials

Energy Technology Data Exchange (ETDEWEB)

Jaramillo, Thomas F.; Baeck, Sung-Hyeon; Kleiman-Shwarsctein, Alan; Stucky, Galen D. (PI); McFarland, Eric W. (PI)

2004-10-25

Solar photoelectrochemical water-splitting has long been viewed as one of the “holy grails” of chemistry because of its potential impact as a clean, renewable method of fuel production. Several known photocatalytic semiconductors can be used; however, the fundamental mechanisms of the process remain poorly understood and no known material has the required properties for cost effective hydrogen production. In order to investigate morphological and compositional variations in metal oxides as they relate to opto-electrochemical properties, we have employed a combinatorial methodology using automated, high-throughput, electrochemical synthesis and screening together with conventional solid-state methods. This report discusses a number of novel, high-throughput instruments developed during this project for the expeditious discovery of improved materials for photoelectrochemical hydrogen production. Also described within this report are results from a variety of materials (primarily tungsten oxide, zinc oxide, molybdenum oxide, copper oxide and titanium dioxide) whose properties were modified and improved by either layering, inter-mixing, or doping with one or more transition metals. Furthermore, the morphologies of certain materials were also modified through the use of structure directing agents (SDA) during synthesis to create mesostructures (features 2-50 nm) that increased surface area and improved rates of hydrogen production.

Potential of hydrogen production from wind energy in Pakistan

International Nuclear Information System (INIS)

Uqaili, M. A.; Harijan, K.; Memon, M.

2007-01-01

The transport sector consumes about 34% of the total commercial energy consumption in Pakistan. About 97% of fuel used in this sector is oil and the remaining 3% is CNG and electricity. The indigenous reserves of oil and gas are limited and the country is heavily dependent on the import of oil. The oil import bill is serious strain on the country's economy. The production, transportation and consumption of fossil fuels also degrade the environment. Therefore, it is important to explore the opportunities for clean renewable energy for long-term energy supply in the transport sector. Sindh, the second largest province of Pakistan, has about 250 km long coastline. The estimated average annual wind speed at 50 m height at almost all sites is about 6-7 m/s, indicating that Sindh has the potential to effectively utilize wind energy source for power generation and hydrogen production. A system consisting of wind turbines coupled with electrolyzers is a promising design to produce hydrogen. This paper presents an assessment of the potential of hydrogen production from wind energy in the coastal area of Sindh, Pakistan. The estimated technical potential of wind power is 386 TWh per year. If the wind electricity is used to power electrolyzers, 347.4 TWh hydrogen can be produced annually, which is about 1.2 times the total energy consumption in the transport sector of Pakistan in 2005. The substitution of oil with renewable hydrogen is essential to increase energy independence, improve domestic economies, and reduce greenhouse gas and other harmful emissions

Technical Integration of Nuclear Hydrogen Production Technology

International Nuclear Information System (INIS)

Lee, Ki Young; Park, J. K.; Chang, J. H.

2009-04-01

These works focus on the development of attainment indices for nuclear hydrogen key technologies, the analysis of the hydrogen production process and the performance estimation for hydrogen production systems, and the assessment of the nuclear hydrogen production cost. For assessing the degree of attainments in comparison with the final goals of VHTR technologies in progress of researches, subdivided are the prerequisite items confirmed to the NHDD concepts. We developed and applied R and D quality management methodology to meet 'Development of Key Technologies for Nuclear Hydrogen' project. And we also distributed R and D QAM and R and D QAP to each teams and are in operation. The preconceptual flow diagrams of SI, HTSE, and HyS processes are introduced and their material and energy balances have been proposed. The hydrogen production thermal efficiencies of not only the SI process as a reference process but also the HTSE and HyS processes were also estimated. Technical feasibility assessments of SI, HTSE, and HyS processes have been carried out by using the pair-wise comparison and analytic hierarchy process, and it is revealed that the experts are considering the SI process as the most feasible process. The secondary helium pathway across the SI process is introduced. Dynamic simulation codes for the H2S04vaporizer, sulfuric acid and sulfur trioxide decomposers, and HI decomposer on the secondary helium pathway and for the primary and secondary sulfuric acid distillation columns, HIx solution distillation column, and preheater for HI vapor have been developed and integrated

Hydrogen production from steam methane reforming and electrolysis as part of a near-term hydrogen infrastructure

International Nuclear Information System (INIS)

Roberts, K.

2003-01-01

Building a complete hydrogen infrastructure for a transportation system based on Fuel Cells (FC) and hydrogen is a risky and expensive ordeal, especially given that it is not known with complete certainty that Fuel Cells will indeed replace the gasoline ICE. But how can we expect the diffusion of an automotive technology if there is no infrastructure to support its fuel needs? This gives rise to a chicken and egg type problem. One way to get around this problem is to produce hydrogen when and where it is needed. This solves the problems of high costs associated with expensive pipeline distribution networks, the high energy-intensities associated with liquefaction of hydrogen and the high costs of cryogenic equipment. This paper will consider the advantages and disadvantages of two such hydrogen production mechanisms, namely, onsite production of hydrogen from Electrolysis and onsite production of hydrogen from Steam Methane Reforming (SMR). Although SMR hydrogen may be more economical due to the availability and low cost of methane, under certain market and technological conditions onsite electrolytic hydrogen can be more attractive. The paper analyses the final price of delivered hydrogen based on its sensitivity to market conditions and technology developments. (author)

Production, storage, transporation and utilization of hydrogen

International Nuclear Information System (INIS)

Akiba, E.

1992-01-01

Hydrogen is produced from water and it can be used for fuel. Water is formed again by combustion of hydrogen with oxygen in the air. Hydrogen is an ideal fuel because hydrogen itself and gases formed by the combustion of hydrogen are not greenhouse and ozone layer damaging gases. Therefore, hydrogen is the most environmental friendly fuel that we have ever had. Hydrogen gas does not naturally exist. Therefore, hydrogen must be produced from hydrogen containing compounds such as water and hydrocarbons by adding energy. At present, hydrogen is produced in large scale as a raw material for the synthesis of ammonia, methanol and other chemicals but not for fuel. In other words, hydrogen fuel has not been realized but will be actualized in the near future. In this paper hydrogen will be discussed as fuel which will be used for aircraft, space application, power generation, combustion, etc. Especially, production of hydrogen is a very important technology for achieving hydrogen energy systems. Storage, transportation and utilization of hydrogen fuel will also be discussed in this paper

Effect of pH and sulfate concentration on hydrogen production using anaerobic mixed microflora

Energy Technology Data Exchange (ETDEWEB)

Hwang, Jae-Hoon; Choi, Jeong-A.; Bhatnagar, Amit; Kumar, Eva; Jeon, Byong-Hun [Department of Environmental Engineering, Yonsei University, Wonju, Gangwon-do, 220-710 (Korea); Abou-Shanab, R.A.I. [Department of Environmental Engineering, Yonsei University, Wonju, Gangwon-do, 220-710 (Korea); Department of Environmental Biotechnology, Mubarak City for Scientific Research, Alexandria (Egypt); Min, Booki [Department of Environmental Science and Engineering, Kyung Hee University, Yongin-Si, Gyeonggi-Do 446-701 (Korea); Song, Hocheol; Kim, Yong Je [Geologic Environment Division, KIGAM, Daejeon, 305-350 (Korea); Choi, Jaeyoung [Korea Institute of Science and Technology (KIST), Gangneung Institute, Gangneung 210-340 (Korea); Lee, Eung Seok [Geological Sciences, College of Arts and Sciences, Ohio University, Athens, OH 45701-2979 (United States); Um, Sukkee [School of Mechanical Engineering, Hanyang University, 17 Haengdang-Dong, Seongdong-Gu, Seoul, 133-791 (Korea); Lee, Dae Sung [Petroleum and Marine Research Department, KIGAM, Daejeon (Korea)

2009-12-15

The effects of varying sulfate concentrations with pH on continuous fermentative hydrogen production were studied using anaerobic mixed cultures growing on a glucose substrate in a chemostat reactor. The maximum hydrogen production rate was 2.8 L/day at pH 5.5 and sulfate concentration of 3000 mg/L. Hydrogen production and residual sulfate level decreased with increasing the pH from 5.5 to 6.2. The volatile fatty acids (VFAs) and ethanol fractions in the effluent were in the order of butyric acid (HBu) > acetic acid (HAc) > ethanol > propionic acid (HPr). Fluorescence In Situ Hybridization (FISH) analysis revealed the presence of hydrogen producing bacteria (HPB) under all pH ranges while sulfate reducing bacteria (SRB) were present at pH 5.8 and 6.2. The inhibition in hydrogen production by SRB at pH 6.2 diminished entirely by lowering to pH 5.5, at which activity of SRB is substantially suppressed. (author)

Photo-fermentative bacteria aggregation triggered by L-cysteine during hydrogen production.

Science.gov (United States)

Xie, Guo-Jun; Liu, Bing-Feng; Xing, De-Feng; Nan, Jun; Ding, Jie; Ren, Nan-Qi

2013-05-03

Hydrogen recovered from organic wastes and solar energy by photo-fermentative bacteria (PFB) has been suggested as a promising bioenergy strategy. However, the use of PFB for hydrogen production generally suffers from a serious biomass washout from photobioreactor, due to poor flocculation of PFB. In the continuous operation, PFB cells cannot be efficiently separated from supernatant and rush out with effluent from reactor continuously, which increased the effluent turbidity, meanwhile led to increases in pollutants. Moreover, to replenish the biomass washout, substrate was continuously utilized for cell growth rather than hydrogen production. Consequently, the poor flocculability not only deteriorated the effluent quality, but also decreased the potential yield of hydrogen from substrate. Therefore, enhancing the flocculability of PFB is urgent necessary to further develop photo-fermentative process. Here, we demonstrated that L-cysteine could improve hydrogen production of Rhodopseudomonas faecalis RLD-53, and more importantly, simultaneously trigger remarkable aggregation of PFB. Experiments showed that L-cysteine greatly promoted the production of extracellular polymeric substances, especially secretion of protein containing more disulfide bonds, and help for enhancement stability of floc of PFB. Through formation of disulfide bonds, L-cysteine not only promoted production of EPS, in particular the secretion of protein, but also stabilized the final confirmation of protein in EPS. In addition, the cell surface elements and functional groups, especially surface charged groups, have also been changed by L-cysteine. Consequently, absolute zeta potential reached a minimum value at 1.0 g/l of L-cysteine, which obviously decreased electrostatic repulsion interaction energy based on DLVO theory. Total interaction energy barrier decreased from 389.77 KT at 0.0 g/l of L-cysteine to 127.21 kT at 1.0 g/l. Thus, the strain RLD-53 overcame the total energy barrier and

Metabolic flux analysis of the hydrogen production potential in Synechocystis sp. PCC6803

Energy Technology Data Exchange (ETDEWEB)

Navarro, E. [Departamento de Lenguajes y Ciencias de la Computacion, Campus de Teatrinos, Universidad de Malaga, 29071 Malaga (Spain); Montagud, A.; Fernandez de Cordoba, P.; Urchueguia, J.F. [Instituto Universitario de Matematica Pura y Aplicada, Universidad Politecnica de Valencia, Camino de Vera 14, 46022 Valencia (Spain)

2009-11-15

Hydrogen is a promising energy vector; however, finding methods to produce it from renewable sources is essential to allow its wide-scale use. In that line, biological hydrogen production, although it is considered as a possible alternative, requires substantial improvements to overcome its present low yields. In that direction, genetic manipulation probably will play a central role and from that point of view metabolic flux analysis (MFA) constitutes an important tool to guide a priori most suitable genetic modifications oriented to a hydrogen yield increase. In this work MFA has been applied to analyze hydrogen photoproduction of Synechocystis sp. PCC6803. Flux analysis was carried out based on literature data and several basic fluxes were estimated in different growing conditions of the system. From this analysis, an upper limit for hydrogen photoproduction has been determined indicating a wide margin for improvement. MFA was also used to find a feasible operating space for hydrogen production, which avoids oxygen inhibition, one of the most important limitations to make hydrogen production cost effective. In addition, a set of biotechnological strategies are proposed that would be consistent with the performed mathematical analysis. (author)

Economical hydrogen production by electrolysis using nano pulsed DC

Energy Technology Data Exchange (ETDEWEB)

Dharmaraj, C.H. [Tangedco, Tirunelveli, ME Environmental Engineering (India); Adshkumar, S. [Department of Civil Engineering, Anna University of Technology Tirunelveli, Tirunelveli - 627007 (India)

2012-07-01

Hydrogen is an alternate renewable eco fuel. The environmental friendly hydrogen production method is electrolysis. The cost of electrical energy input is major role while fixing hydrogen cost in the conventional direct current Electrolysis. Using nano pulse DC input makes the input power less and economical hydrogen production can be established. In this investigation, a lab scale electrolytic cell developed and 0.58 mL/sec hydrogen/oxygen output is obtained using conventional and nano pulsed DC. The result shows that the nano pulsed DC gives 96.8 % energy saving.

Hydrogen peroxide production is affected by oxygen levels in mammalian cell culture.

Science.gov (United States)

Maddalena, Lucas A; Selim, Shehab M; Fonseca, Joao; Messner, Holt; McGowan, Shannon; Stuart, Jeffrey A

2017-11-04

Although oxygen levels in the extracellular space of most mammalian tissues are just a few percent, under standard cell culture conditions they are not regulated and are often substantially higher. Some cellular sources of reactive oxygen species, like NADPH oxidase 4, are sensitive to oxygen levels in the range between 'normal' physiological (typically 1-5%) and standard cell culture (up to 18%). Hydrogen peroxide in particular participates in signal transduction pathways via protein redox modifications, so the potential increase in its production under standard cell culture conditions is important to understand. We measured the rates of cellular hydrogen peroxide production in some common cell lines, including C2C12, PC-3, HeLa, SH-SY5Y, MCF-7, and mouse embryonic fibroblasts (MEFs) maintained at 18% or 5% oxygen. In all instances the rate of hydrogen peroxide production by these cells was significantly greater at 18% oxygen than at 5%. The increase in hydrogen peroxide production at higher oxygen levels was either abolished or substantially reduced by treatment with GKT 137831, a selective inhibitor of NADPH oxidase subunits 1 and 4. These data indicate that oxygen levels experienced by cells in culture influence hydrogen peroxide production via NADPH oxidase 1/4, highlighting the importance of regulating oxygen levels in culture near physiological values. However, we measured pericellular oxygen levels adjacent to cell monolayers under a variety of conditions and with different cell lines and found that, particularly when growing at 5% incubator oxygen levels, pericellular oxygen was often lower and variable. Together, these observations indicate the importance, and difficulty, of regulating oxygen levels experienced by cells in culture. Copyright © 2017 Elsevier Inc. All rights reserved.

Bio-hydrogen production by Enterobacter asburiae SNU-1 isolated from a landfill

Energy Technology Data Exchange (ETDEWEB)

Jong-Hwan Shin; Jong Hyun Yoon; Tai Hyun Park [School of Chemical and Biological Engineering, Seoul National University, Seoul 151-744, (Korea, Republic of)

2006-07-01

A new fermentative hydrogen-producing bacterium was isolated from a landfill, and it was identified as Enterobacter asburiae strain using a genomic DNA hybridization method. Environmental factors and metabolic flux influencing the hydrogen production were investigated, including pH, initial glucose and formate concentrations. The major hydrogen production pathway of this strain is considered to be a formate pathway by using formate hydrogen lyase (FHL). Optimum pH for the hydrogen production was pH 7.0 in PYG medium, at which hydrogen production/unit volume and overall hydrogen productivity were 2615 ml/l and 174 ml H{sub 2}/l/hr, respectively, at 25 g glucose/l. The maximum hydrogen productivity was estimated to be 417 ml H{sub 2}/l/hr at 15 g glucose/l. This strain produced bio-hydrogen mostly in the stationary phase, in which formate concentration was high. In this paper, hydrogen production was tried in formate medium after cell harvest. (authors)

Bio-hydrogen production by Enterobacter asburiae SNU-1 isolated from a landfill

International Nuclear Information System (INIS)

Jong-Hwan Shin; Jong Hyun Yoon; Tai Hyun Park

2006-01-01

A new fermentative hydrogen-producing bacterium was isolated from a landfill, and it was identified as Enterobacter asburiae strain using a genomic DNA hybridization method. Environmental factors and metabolic flux influencing the hydrogen production were investigated, including pH, initial glucose and formate concentrations. The major hydrogen production pathway of this strain is considered to be a formate pathway by using formate hydrogen lyase (FHL). Optimum pH for the hydrogen production was pH 7.0 in PYG medium, at which hydrogen production/unit volume and overall hydrogen productivity were 2615 ml/l and 174 ml H 2 /l/hr, respectively, at 25 g glucose/l. The maximum hydrogen productivity was estimated to be 417 ml H 2 /l/hr at 15 g glucose/l. This strain produced bio-hydrogen mostly in the stationary phase, in which formate concentration was high. In this paper, hydrogen production was tried in formate medium after cell harvest. (authors)

Hydrogen production from biomass pyrolysis gas via high temperature steam reforming process

International Nuclear Information System (INIS)

Wongchang, Thawatchai; Patumsawad, Suthum

2010-01-01

Full text: The aim of this work has been undertaken as part of the design of continuous hydrogen production using the high temperature steam reforming process. The steady-state test condition was carried out using syngas from biomass pyrolysis, whilst operating at high temperatures between 600 and 1200 degree Celsius. The main reformer operating parameters (e.g. temperature, resident time and steam to biomass ratio (S/B)) have been examined in order to optimize the performance of the reformer. The operating temperature is a key factor in determining the extent to which hydrogen production is increased at higher temperatures (900 -1200 degree Celsius) whilst maintaining the same as resident time and S/B ratio. The effects of exhaust gas composition on heating value were also investigated. The steam reforming process produced methane (CH 4 ) and ethylene (C 2 H 4 ) between 600 to 800 degree Celsius and enhanced production ethane (C 2 H 6 ) at 700 degree Celsius. However carbon monoxide (CO) emission was slightly increased for higher temperatures all conditions. The results show that the use of biomass pyrolysis gas can produce higher hydrogen production from high temperature steam reforming. In addition the increasing reformer efficiency needs to be optimized for different operating conditions. (author)

Utilization of solar and nuclear energy for hydrogen production

International Nuclear Information System (INIS)

Fischer, M.

1987-01-01

Although the world-wide energy supply situation appears to have eased at present, non-fossil primary energy sources and hydrogen as a secondary energy carrier will have to take over a long-term and increasing portion of the energy supply system. The only non-fossil energy sources which are available in relevant quantities, are nuclear energy, solar energy and hydropower. The potential of H 2 for the extensive utilization of solar energy is of particular importance. Status, progress and development potential of the electrolytic H 2 production with photovoltaic generators, solar-thermal power plants and nuclear power plants are studied and discussed. The joint German-Saudi Arabian Research, Development and Demonstration Program HYSOLAR for the solar hydrogen production and utilization is summarized. (orig.)

Hydrogen and syngas production from sewage sludge via steam gasification

Energy Technology Data Exchange (ETDEWEB)

Nipattummakul, Nimit [The Combustion Laboratory, Dept. of Mechanical Engineering, University of Maryland, College Park, MD (United States); The Waste Incineration Research Center, Dept. of Mechanical and Aerospace Engineering, King Mongkut' s University of Technology, North Bangkok (Thailand); Ahmed, Islam I.; Gupta, Ashwani K. [The Combustion Laboratory, Dept. of Mechanical Engineering, University of Maryland, College Park, MD (United States); Kerdsuwan, Somrat [The Waste Incineration Research Center, Dept. of Mechanical and Aerospace Engineering, King Mongkut' s University of Technology, North Bangkok (Thailand)

2010-11-15

High temperature steam gasification is an attractive alternative technology which can allow one to obtain high percentage of hydrogen in the syngas from low-grade fuels. Gasification is considered a clean technology for energy conversion without environmental impact using biomass and solid wastes as feedstock. Sewage sludge is considered a renewable fuel because it is sustainable and has good potential for energy recovery. In this investigation, sewage sludge samples were gasified at various temperatures to determine the evolutionary behavior of syngas characteristics and other properties of the syngas produced. The syngas characteristics were evaluated in terms of syngas yield, hydrogen production, syngas chemical analysis, and efficiency of energy conversion. In addition to gasification experiments, pyrolysis experiments were conducted for evaluating the performance of gasification over pyrolysis. The increase in reactor temperature resulted in increased generation of hydrogen. Hydrogen yield at 1000 C was found to be 0.076 g{sub gas} g{sub sample}{sup -1}. Steam as the gasifying agent increased the hydrogen yield three times as compared to air gasification. Sewage sludge gasification results were compared with other samples, such as, paper, food wastes and plastics. The time duration for sewage sludge gasification was longer as compared to other samples. On the other hand sewage sludge yielded more hydrogen than that from paper and food wastes. (author)

Supercritical water gasification of landfill leachate for hydrogen production in the presence and absence of alkali catalyst.

Science.gov (United States)

Weijin, Gong; Binbin, Li; Qingyu, Wang; Zuohua, Huang; Liang, Zhao

2018-03-01

Gasification of landfill leachate in supercritical water using batch-type reactor is investigated. Alkali such as NaOH, KOH, K 2 CO 3 , Na 2 CO 3 is used as catalyst. The effect of temperature (380-500 °C), retention time (5-25 min), landfill leachate concentration (1595 mg L -1 -15,225 mg L -1 ), catalyst adding amount (1-10 wt%) on hydrogen mole fraction, hydrogen yield, carbon gasification rate, COD, TOC, TN removal efficiency are investigated. The results showed that gaseous products mainly contained hydrogen, methane, carbon dioxide and carbon monoxide without addition of catalyst. However, the main gaseous products are hydrogen and methane with addition of NaOH, KOH, K 2 CO 3 , Na 2 CO 3 . In the absence of alkali catalyst, the effect of temperature on landfill leachate gasification is positive. Hydrogen mole fraction, hydrogen yield, carbon gasification ratio increase with temperature, which maximum value being 55.6%, 107.15 mol kg -1 , 71.96% is obtained at 500 °C, respectively. Higher raw landfill leachate concentration leads to lower hydrogen production and carbon gasification rate. The suitable retention time is suggested to be 15 min for higher hydrogen production and carbon gasification rate. COD, TOC and TN removal efficiency also increase with increase of temperature, decrease of landfill leachate concentration. In the presence of catalyst, the hydrogen production is obviously promoted by addition of alkali catalyst. the effect of catalysts on hydrogen production is in the following order: NaOH ＞ KOH ＞ Na 2 CO 3  ＞ K 2 CO 3 . The maximum hydrogen mole fraction and hydrogen yield being 74.40%, 70.05 mol kg -1 is obtained with adding amount of 5 wt% NaOH at 450 °C, 28 MPa, 15 min. Copyright © 2017. Published by Elsevier Ltd.

Solar photochemical production of HBr for off-peak electrolytic hydrogen production

Energy Technology Data Exchange (ETDEWEB)

Heaton, H. [Solar Reactor Technologies Inc., Miami, FL (United States)

1996-10-01

Progress is reported on the development of a unique and innovative hydrogen production concept utilizing renewable (Solar) energy and incorporating energy storage. The concept is based on a solar-electrolytic system for production of hydrogen and oxygen. It employs water, bromine, solar energy, and supplemental electrical power. The process consumes only water, sunlight and off-peak electricity, and produces only hydrogen, oxygen, and peaking electrical power. No pollutants are emitted, and fossil fuels are not consumed. The concept is being developed by Solar Reactor Technologies, Inc., (SRT) under the auspices of a Cooperative Agreement with the U.S. Department of Energy (DOE).

Substrate and product inhibition of hydrogen production by the extreme thermophile, Caldicellulosiruptor saccharolyticus

NARCIS (Netherlands)

Niel, van E.W.J.; Claassen, P.A.M.; Stams, A.J.M.

2003-01-01

Substrate and product inhibition of hydrogen production during sucrose fermentation by the extremely thermophilic bacterium Caldicellulosiruptor saccharolyticus was studied. The inhibition kinetics were analyzed with a noncompetitive, nonlinear inhibition model. Hydrogen was the most severe

Use of nuclear energy for hydrogen production

International Nuclear Information System (INIS)

Axente, Damian

2006-01-01

Full text: The potentials of three hydrogen production processes under development for the industrial production of hydrogen using nuclear energy, namely the advanced electrolysis the steam reforming, the sulfur-iodine water splitting cycle, are compared and evaluated in this paper. Water electrolysis and steam reforming of methane are proven and used extensively today for the production of hydrogen. The overall thermal efficiency of the electrolysis includes the efficiency of the electrical power generation and of the electrolysis itself. The electrolysis process efficiency is about 75 % and of electrical power generation is only about 30 %, the overall thermal efficiency for H 2 generation being about 25 %. Steam reforming process consists of reacting methane (or natural gas) and steam in a chemical reactor at 800-900 deg. C, with a thermal efficiency of about 70 %. In a reforming process, with heat supplied by nuclear reactor, the heat must be supplied by a secondary loop from the nuclear side and be transferred to the methane/steam mixture, via a heat exchanger type reactor. The sulfur-iodine cycle, a thermochemical water splitting, is of particular interest because it produces hydrogen efficiently with no CO 2 as byproduct. If heated with a nuclear source it could prove to be an ideal environmental solution to hydrogen production. Steam reforming remains the cheapest hydrogen production method based on the latest estimates, even when implemented with nuclear reactor. The S-I cycle offers a close second solution and the electrolysis is the most expensive of the options for industrial H 2 production. The nuclear plant could power electrolysis operations right away; steam reforming with nuclear power is a little bit further off into the future, the first operation with nuclear facility is expected to have place in Japan in 2008. The S-I cycle implementation is still over the horizon, it will be more than 10 years until we will see that cycle in full scale

Thermodynamics of Hydrogen Production from Dimethyl Ether Steam Reforming and Hydrolysis

Energy Technology Data Exchange (ETDEWEB)

T.A. Semelsberger

2004-10-01

The thermodynamic analyses of producing a hydrogen-rich fuel-cell feed from the process of dimethyl ether (DME) steam reforming were investigated as a function of steam-to-carbon ratio (0-4), temperature (100 C-600 C), pressure (1-5 atm), and product species: acetylene, ethanol, methanol, ethylene, methyl-ethyl ether, formaldehyde, formic acid, acetone, n-propanol, ethane and isopropyl alcohol. Results of the thermodynamic processing of dimethyl ether with steam indicate the complete conversion of dimethyl ether to hydrogen, carbon monoxide and carbon dioxide for temperatures greater than 200 C and steam-to-carbon ratios greater than 1.25 at atmospheric pressure (P = 1 atm). Increasing the operating pressure was observed to shift the equilibrium toward the reactants; increasing the pressure from 1 atm to 5 atm decreased the conversion of dimethyl ether from 99.5% to 76.2%. The order of thermodynamically stable products in decreasing mole fraction was methane, ethane, isopropyl alcohol, acetone, n-propanol, ethylene, ethanol, methyl-ethyl ether and methanol--formaldehyde, formic acid, and acetylene were not observed. The optimal processing conditions for dimethyl ether steam reforming occurred at a steam-to-carbon ratio of 1.5, a pressure of 1 atm, and a temperature of 200 C. Modeling the thermodynamics of dimethyl ether hydrolysis (with methanol as the only product considered), the equilibrium conversion of dimethyl ether is limited. The equilibrium conversion was observed to increase with temperature and steam-to-carbon ratio, resulting in a maximum dimethyl ether conversion of approximately 68% at a steam-to-carbon ratio of 4.5 and a processing temperature of 600 C. Thermodynamically, dimethyl ether processed with steam can produce hydrogen-rich fuel-cell feeds--with hydrogen concentrations exceeding 70%. This substantiates dimethyl ether as a viable source of hydrogen for PEM fuel cells.

Primary energy sources for hydrogen production

International Nuclear Information System (INIS)

Hassmann, K.; Kuehne, H.M.

1993-01-01

The costs for hydrogen production through water electrolysis are estimated, assuming the electricity is produced from solar, hydro-, fossil, or nuclear power. The costs for hydrogen end-use in the power generation, heat and transportation sectors are also calculated, based on a state of the art technology and a more advanced technology expected to represent the state by the year 2010. The costs for hydrogen utilization (without energy taxes) are shown to be higher than current prices for fossil fuels (including taxes). Without restrictions imposed on fossil fuel consumption, hydrogen shall not gain a significant market share in either of the cases discussed. 2 figs., 3 tabs., 4 refs

Production of hydrogen by microbial fermentation

Energy Technology Data Exchange (ETDEWEB)

Roychowdhury, S.; Cox, D.; Levandowsky, M.

1988-01-01

Production of hydrogen by defined and undefined bacterial cultures was studied, using pure sugars (glucose and maltose) or natural sources rich in either pure sugars or polysaccharides. The latter included sugar cane juice, corn pulp (enzymatically treated or untreated), and enzymatically treated paper. Mixed microbial flora from sewage and landfill sediments, as well as pure and mixed cultures of known coliform bacteria produced mixtures of hydrogen and carbon dioxide at 37/sup 0/C and 55/sup 0/C, with hydrogen concentrations as high as 87%. In the case of the pure glucose substrate, an average yield of 0.7 mol hydrogen per mol glucose was obtained.

VHTR-based Nuclear Hydrogen Plant Analysis for Hydrogen Production with SI, HyS, and HTSE Facilities

International Nuclear Information System (INIS)

Shin, Youngjoon; Lee, Taehoon; Lee, Kiyoung; Kim, Minhwan

2016-01-01

In this paper, analyses of material and heat balances on the SI, HyS, and HTSE processes coupled to a Very High Temperature gas-cooled Reactor (VHTR) were performed. The hydrogen production efficiency including the thermal to electric energy ratio demanded from each process is found and the normalized evaluation results obtained from three processes are compared to each other. The currently technological issues to maintain the long term continuous operation of each process will be discussed at the conference site. VHTR-based nuclear hydrogen plant analysis for hydrogen production with SI, HyS, and HTSE facilities has been carried out to determine the thermal efficiency. It is evident that the thermal to electrical energy ratio demanded from each hydrogen production process is an important parameter to select the adequate process for hydrogen production. To improve the hydrogen production efficiency in the SI process coupled to the VHTR without electrical power generation, the demand of electrical energy in the SI process should be minimized by eliminating an electrodialysis step to break through the azeotrope of the HI/I_2/H_2O ternary aqueous solution

Increasing hydrogen storage capacity using tetrahydrofuran.

Science.gov (United States)

Sugahara, Takeshi; Haag, Joanna C; Prasad, Pinnelli S R; Warntjes, Ashleigh A; Sloan, E Dendy; Sum, Amadeu K; Koh, Carolyn A

2009-10-21

Hydrogen hydrates with tetrahydrofuran (THF) as a promoter molecule are investigated to probe critical unresolved observations regarding cage occupancy and storage capacity. We adopted a new preparation method, mixing solid powdered THF with ice and pressurizing with hydrogen at 70 MPa and 255 +/- 2 K (these formation conditions are insufficient to form pure hydrogen hydrates). All results from Raman microprobe spectroscopy, powder X-ray diffraction, and gas volumetric analysis show a strong dependence of hydrogen storage capacity on THF composition. Contrary to numerous recent reports that claim it is impossible to store H(2) in large cages with promoters, this work shows that, below a THF mole fraction of 0.01, H(2) molecules can occupy the large cages of the THF+H(2) structure II hydrate. As a result, by manipulating the promoter THF content, the hydrogen storage capacity was increased to approximately 3.4 wt % in the THF+H(2) hydrate system. This study shows the tuning effect may be used and developed for future science and practical applications.

A hydrogen production experiment by the thermo-chemical and electrolytic hybrid hydrogen production in lower temperature range. System viability and preliminary thermal efficiency estimation

International Nuclear Information System (INIS)

Takai, Toshihide; Nakagiri, Toshio; Inagaki, Yoshiyuki

2008-10-01

A new experimental apparatus by the thermo-chemical and electrolytic Hybrid-Hydrogen production in Lower Temperature range (HHLT) was developed and hydrogen production experiment was performed to confirm the system operability. Hydrogen production efficiency was estimated and technical problems were clarified through the experimental results. Stable operation of the SO 3 electrolysis cell and the sulfur dioxide solution electrolysis cell were confirmed during experimental operation and any damage which would be affected solid operation was not detected under post operation inspection. To improve hydrogen production efficiency, it was found that the reduction of sulfuric acid circulation and the decrease in the cell voltage were key issues. (author)

Biological Hydrogen Production from Corn-Syrup Waste Using a Novel System

Directory of Open Access Journals (Sweden)

George Nakhla

2009-06-01

Full Text Available The reported patent-pending system comprises a novel biohydrogen reactor with a gravity settler for decoupling of SRT from HRT. The biohydrogenator was operated for 100 days at 37 °C, hydraulic retention time 8 h and solids retention time ranging from 2.2–2.5 days. The feed was a corn-syrup waste generated as a byproduct from an industrial facility for bioethanol production located in southwestern Ontario, Canada. The system was initially started up with a synthetic feed containing glucose at concentration of 8 g/L and other essential inorganics. Anaerobicaly-digested sludge from the St. Mary’s wastewater treatment plant (St. Mary, Ontario, Canada was used as the seed, and was heat treated at 70 °C for 30 min to inhibit methanogens. After 10 days, when the hydrogen production was steady, the corn-syrup waste was introduced to the system. Glucose was the main constituent in the corn-syrup; its concentration was varied over a period of 90 days from 8 to 25 g/L. The change in glucose concentration was used to study the impact of variable organic loading on the stability of hydrogen production in the biohydrogenator. Hydrogen production rate increased from 10 L H2/L·d to 34 L H2/L·d with the increase of organic loading rate (OLR from 26 to 81 gCOD/L·d, while a maximum hydrogen yield of 430 mL H2/gCOD was achieved in the system with an overall average of 385 mL H2/gCOD.

Hydrogen Production from Semiconductor-based Photocatalysis via Water Splitting

Directory of Open Access Journals (Sweden)

Jeffrey C. S. Wu

2012-10-01

Full Text Available Hydrogen is the ideal fuel for the future because it is clean, energy efficient, and abundant in nature. While various technologies can be used to generate hydrogen, only some of them can be considered environmentally friendly. Recently, solar hydrogen generated via photocatalytic water splitting has attracted tremendous attention and has been extensively studied because of its great potential for low-cost and clean hydrogen production. This paper gives a comprehensive review of the development of photocatalytic water splitting for generating hydrogen, particularly under visible-light irradiation. The topics covered include an introduction of hydrogen production technologies, a review of photocatalytic water splitting over titania and non-titania based photocatalysts, a discussion of the types of photocatalytic water-splitting approaches, and a conclusion for the current challenges and future prospects of photocatalytic water splitting. Based on the literatures reported here, the development of highly stable visible–light-active photocatalytic materials, and the design of efficient, low-cost photoreactor systems are the key for the advancement of solar-hydrogen production via photocatalytic water splitting in the future.

Co-production of hydrogen and electricity with CO{sub 2} capture

Energy Technology Data Exchange (ETDEWEB)

Arienti, S.; Cotone, P.; Davison, J. [Foster Wheeler Italiana (Italy)

2007-07-01

This paper summarizes the results of a study carried out by Foster Wheeler for the IEA Greenhouse Gas R & D Programme that focused on different IGCC configurations with CO{sub 2} capture and H{sub 2} production. The three following main cases are compared: production of hydrogen, with minimum amount of electricity for a stand-alone plant production; co-production of the optimum hydrogen/electricity ratio; and co-production of hydrogen and electricity in a flexible plant that varies the hydrogen/electricity ratio. The paper reviews three available gasification technologies and presents the results of a more detailed evaluation of the selected one. The scope of this paper is to underline possible advantages of hydrogen and electricity co-production from coal, that is likely going to replace natural gas and petroleum as a source of hydrogen in the long term. Expected advantage of co-production will be the ability to vary the hydrogen/electricity ratio to meet market demands. A natural gas, diesel and gasoline demand market analysis has been performed for the Netherlands and the USA to determine the expected future hydrogen demand. Plant performance and costs are established and electric power production costs are evaluated. Electricity and hydrogen co-production plants are compared to plants that produce electricity only, with and without CO{sub 2} capture, to evaluate the costs of CO{sub 2} avoidance. 4 refs., 8 figs., 4 tabs.

Efficiency analysis of hydrogen production methods from biomass

NARCIS (Netherlands)

Ptasinski, K.J.

2008-01-01

Abstract: Hydrogen is considered as a universal energy carrier for the future, and biomass has the potential to become a sustainable source of hydrogen. This article presents an efficiency analysis of hydrogen production processes from a variety of biomass feedstocks by a thermochemical method –

Photocurrent increase by metal modification of Fe{sub 2}O{sub 3} photoanodes and its effect on photoelectrocatalytic hydrogen production by degradation of organic substances

Energy Technology Data Exchange (ETDEWEB)

Iervolino, Giuseppina [Department of Industrial Engineering, University of Salerno, Via Giovanni Paolo II, 132, Fisciano, Salerno, Italy, (Italy); Tantis, Iosif [Department of Chemical Engineering, University of Patras, 26500, Patras (Greece); Sygellou, Lamprini [FORTH/ICE-HT, P.O. Box 1414, 26504, Patras (Greece); Vaiano, Vincenzo, E-mail: vvaiano@unisa.it [Department of Industrial Engineering, University of Salerno, Via Giovanni Paolo II, 132, Fisciano, Salerno, Italy, (Italy); Sannino, Diana [Department of Industrial Engineering, University of Salerno, Via Giovanni Paolo II, 132, Fisciano, Salerno, Italy, (Italy); Lianos, Panagiotis, E-mail: lianos@upatras.gr [Department of Chemical Engineering, University of Patras, 26500, Patras (Greece)

2017-04-01

Highlights: • Metals-modified hematite photoanodes prepared by electrodeposition method. • Ti and Ni-modified hematite thin films showed the higher photocurrents values. • The optimal loading of modifier was found at nominal 1% for Ni and 3% for Ti. • The highest H2 production was obtained on 3%Ti-Fe2O3 in the presence of glucose. - Abstract: The present work reports the investigation of photocurrent increase by metal modification of Fe{sub 2}O{sub 3} photoanodes and its effect on photoelectrocatalytic hydrogen production using aqueous solutions containing various organic compounds. Fe{sub 2}O{sub 3} photoanodes were prepared by the electrodeposition method. The efficiency of various metal modifiers of the hematite structure (Ti, Ni, Sn, Co and Cu) has been tested by monitoring the photoelectrochemical behavior of the ensuing photoanodes. Hydrogen production was monitored in an H-shaped reactor using pure and metal-modified hematite films deposited on FTO electrodes as photocatalyst while a combination of commercial carbon paste with dispersed Pt nanoparticles was used as electrocatalyst. In all cases, hydrogen production was obtained by application of a small external electric bias (in the range 0.5- 0.7 V vs Ag/AgCl electrode). Highest photocurrent production has been achieved with a Ti-modified Fe{sub 2}O{sub 3} photoanode in the presence of glucose as sacrificial agent.

Thermodynamic analysis of hydrogen production from biomass gasification

International Nuclear Information System (INIS)

Cohce, M.K.; Dincer, I.; Rosen, M.A.

2009-01-01

'Full Text': Biomass resources have the advantage of being renewable and can therefore contribute to renewable hydrogen production. In this study, an overview is presented of hydrogen production methods in general, and biomass-based hydrogen production in particular. For two methods in the latter category (direct gasification and pyrolysis), assessments are carried out, with the aim of investigating the feasibility of producing hydrogen from biomass and better understanding the potential of biomass as a renewable energy source. A simplified model is presented here for biomass gasification based on chemical equilibrium considerations, and the effects of temperature, pressure and the Gibbs free energy on the equilibrium hydrogen yield are studied. Palm oil (designated C 6 H 10 O 5 ), one of the most common biomass resources in the world, is considered in the analyses. The gasifier is observed to be one of the most critical components of a biomass gasification system, and is modeled using stoichiometric reactions. Various thermodynamic efficiencies are evaluated, and both methods are observed to have reasonably high efficiencies. (author)

The Modular Helium Reactor for Hydrogen Production

International Nuclear Information System (INIS)

E. Harvego; M. Richards; A. Shenoy; K. Schultz; L. Brown; M. Fukuie

2006-01-01

For electricity and hydrogen production, an advanced reactor technology receiving considerable international interest is a modular, passively-safe version of the high-temperature, gas-cooled reactor (HTGR), known in the U.S. as the Modular Helium Reactor (MHR), which operates at a power level of 600 MW(t). For hydrogen production, the concept is referred to as the H2-MHR. Two concepts that make direct use of the MHR high-temperature process heat are being investigated in order to improve the efficiency and economics of hydrogen production. The first concept involves coupling the MHR to the Sulfur-Iodine (SI) thermochemical water splitting process and is referred to as the SI-Based H2-MHR. The second concept involves coupling the MHR to high-temperature electrolysis (HTE) and is referred to as the HTE-Based H2-MHR

Attenuation of cigarette smoke-induced airway mucus production by hydrogen-rich saline in rats.

Directory of Open Access Journals (Sweden)

Yunye Ning

Full Text Available BACKGROUND: Over-production of mucus is an important pathophysiological feature in chronic airway disease such as chronic obstructive pulmonary disease (COPD and asthma. Cigarette smoking (CS is the leading cause of COPD. Oxidative stress plays a key role in CS-induced airway abnormal mucus production. Hydrogen protected cells and tissues against oxidative damage by scavenging hydroxyl radicals. In the present study we investigated the effect of hydrogen on CS-induced mucus production in rats. METHODS: Male Sprague-Dawley rats were divided into four groups: sham control, CS group, hydrogen-rich saline pretreatment group and hydrogen-rich saline control group. Lung morphology and tissue biochemical changes were determined by immunohistochemistry, Alcian Blue/periodic acid-Schiff staining, TUNEL, western blot and realtime RT-PCR. RESULTS: Hydrogen-rich saline pretreatment attenuated CS-induced mucus accumulation in the bronchiolar lumen, goblet cell hyperplasia, muc5ac over-expression and abnormal cell apoptosis in the airway epithelium as well as malondialdehyde increase in the BALF. The phosphorylation of EGFR at Tyr1068 and Nrf2 up-regulation expression in the rat lungs challenged by CS exposure were also abrogated by hydrogen-rich saline. CONCLUSION: Hydrogen-rich saline pretreatment ameliorated CS-induced airway mucus production and airway epithelium damage in rats. The protective role of hydrogen on CS-exposed rat lungs was achieved at least partly by its free radical scavenging ability. This is the first report to demonstrate that intraperitoneal administration of hydrogen-rich saline protected rat airways against CS damage and it could be promising in treating abnormal airway mucus production in COPD.

GAT 4 production and storage of hydrogen. Report July 2004

International Nuclear Information System (INIS)

2004-01-01

This paper concerns two aspects of the hydrogen: the production and the storage. For both parts the challenges and a state of the art are presented. It discusses also the hydrogen production by renewable energies, by solar energy, the hydrogen of hydrocarbons reforming purification, active phases development, thermal transfer simulation. Concerning the hydrogen storage the hydrogen adsorption by large surface solid, the storage by metallic hydrides, the alanates and light hydrides, the adsorption on carbon nano-tubes, the storage in nano-structures, the thermal and mechanical simulation of the hydrogen are presented. (A.L.B.)

Hydrogen Production for Refuelling Applications

Energy Technology Data Exchange (ETDEWEB)

Hulteberg, Christian; Aagesen, Diane (Intelligent Energy, Long Beach, CA (United States))

2009-08-15

/day); Feedstock Cost (USD 0.15 - USD 0.45 per kg); Availability (85% - 95%). The return-on-investment is between USD 90 000 and USD 180 000 in 60 % of the 5 000 simulation runs, which leads to the conclusion that given these assumptions the owning and operation of such a unit can be profitable. As for the performance of the system, it is concluded to be within targets based on the different performance measures reported above. The conversion is in the expected range (80-85%), given the throughput of 16 kg of hydrogen per day. The efficiency as reported is in the acceptable range (approx65%), with some room for improvement within the given system architecture, if desired. However, there is a trade-off between throughput, efficiency and cost that will have to be considered in every redesign of the system. The PSA chosen for the task has performed well during the 200+ hours of operation and there is no doubt that it will be sufficient for the task. The same thing can be said with respect to the system performance with respect to thermo-mechanical stress; which was proven by operating the system for more than 500 hours and performing 58 start-and-stop cycles during the testing. There does not seem to be any major differences between operating on natural gas or methane, based on the testing performed. The slight decrease in hydrogen production can be due to a difference in the H{sub 2}/CO ratio between the various fuels. As expected the efficiency increases with load as well as the hydrogen production rate. Based on the results disseminated above, there is no indication why the current reactor system cannot be configured into a field deployable system. The operation of the system has given valuable experience that will be embedded into any field deployed unit

Enhancement of hydrogen production during waste activated sludge anaerobic fermentation by carbohydrate substrate addition and pH control.

Science.gov (United States)

Chen, Yinguang; Xiao, Naidong; Zhao, Yuxiao; Mu, Hui

2012-06-01

The effects of carbohydrate/protein ratio (CH/Pr) and pH on hydrogen production from waste activated sludge (WAS) were investigated. Firstly, the optimal pH value for hydrogen production was influenced by the CH/Pr ratio, which was pH 10, 9, 8, 8, 8 and 6 at the CH/Pr ratio (COD based) of 0.2 (sole sludge), 1, 2.4, 3.8, 5 and 6.6, respectively. The maximal hydrogen production (100.6 mL/g-COD) was achieved at CH/Pr of 5 and pH 8, which was due to the synergistic effect of carbohydrate addition on hydrogen production, the enhancement of sludge protein degradation and protease and amylase activities, and the suitable fermentation pathway for hydrogen production. As hydrogen consumption was observed at pH 8, in order to further increase hydrogen production a two-step pH control strategy (pH 8+pH 10) was developed and the hydrogen production was further improved by 17.6%. Copyright © 2012 Elsevier Ltd. All rights reserved.

Fermentative hydrogen production by the new marine Pantoea agglomerans isolated from the mangrove sludge

Energy Technology Data Exchange (ETDEWEB)

Zhu, Daling [College of Marine Science and Engineering, Tianjin University of Science and Technology, Tianjin 300457 (China); Wang, Guangce [College of Marine Science and Engineering, Tianjin University of Science and Technology, Tianjin 300457 (China); Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071 (China); Qiao, Hongjin; Cai, Jinling [Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071 (China)

2008-11-15

A new fermentative hydrogen-producing bacterium was isolated from mangrove sludge and identified as Pantoea agglomerans using light microscopic examination, biological tests and 16S rRNA gene sequence analysis. The isolated bacterium, designated as P. agglomerans BH-18, is a new strain that has never been optimized as a potential hydrogen-producing bacterium. In this study, the culture conditions and the hydrogen-producing ability of P. agglomerans BH-18 were examined. The strain was a salt-tolerant facultative anaerobe with the initial optimum pH value at 8.0-9.0 and temperature at 30 C on cell growth. During fermentation, hydrogen started to evolve when cell growth entered late-exponential phase and was mainly produced in the stationary phase. The strain was able to produce hydrogen over a wide range of initial pH from 5 to 10, with an optimum initial pH of 6. The level of hydrogen production was affected by the initial glucose concentration, and the optimum value was found to be 10 g glucose/l. The maximum hydrogen-producing yield (2246 ml/l) and overall hydrogen production rate (160 ml/l/h) were obtained at an initial glucose concentration of 10 g/l and an initial pH value of 7.2 in marine culture conditions. In particular, the level of hydrogen production was also affected by the salt concentration. Hydrogen production reached a higher level in fresh culture conditions than in marine ones. In marine conditions, hydrogen productivity was 108 ml/l/h at an initial glucose concentration of 20 g/l and pH value of 7.2, whereas, it increased by 27% in fresh conditions. In addition, this strain could produce hydrogen using glucose and many other carbon sources such as fructose, sucrose, sorbitol and so on. As a result, it is possible that P. agglomerans BH-18 is used for biohydrogen production and biological treatment of mariculture wastewater and marine organic waste. (author)

Evaluation of Fermentative Hydrogen Production from Single and Mixed Fruit Wastes

Directory of Open Access Journals (Sweden)

Julius Akinbomi

2015-05-01

Full Text Available The economic viability of employing dark fermentative hydrogen from whole fruit wastes as a green alternative to fossil fuels is limited by low hydrogen yield due to the inhibitory effect of some metabolites in the fermentation medium. In exploring means of increasing hydrogen production from fruit wastes, including orange, apple, banana, grape and melon, the present study assessed the hydrogen production potential of singly-fermented fruits as compared to the fermentation of mixed fruits. The fruit feedstock was subjected to varying hydraulic retention times (HRTs in a continuous fermentation process at 55 °C for 47 days. The weight distributions of the first, second and third fruit mixtures were 70%, 50% and 20% orange share, respectively, while the residual weight was shared equally by the other fruits. The results indicated that there was an improvement in cumulative hydrogen yield from all of the feedstock when the HRT was five days. Based on the results obtained, apple as a single fruit and a fruit mixture with 20% orange share have the most improved cumulative hydrogen yields of 504 (29.5% of theoretical yield and 513 mL/g volatile solid (VS (30% of theoretical yield , respectively, when compared to other fruits.

Solar to hydrogen: Compact and cost effective CPV field for rooftop operation and hydrogen production

KAUST Repository

Burhan, Muhammad

2016-11-25

Current commercial CPV systems are designed as large units which are targeted to be installed in open desert fields with high DNI availability. It appeared that the CPV is among some of those technologies which gained very little attention of people, with less customers and market. For conventional PV systems, the installations at the rooftop of commercial and residential buildings have a significant share in the total installed capacity of PV systems. That is why for most of the countries, the PV installations at the rooftop of commercial and residential buildings are aimed to be increased to half of total installed PV. On the other hand, there is no commercial CPV system available to be suitable for rooftop operation, giving motivation for the development of CPV field of compact systems. This paper discusses the development of a CPV field for the rooftop operation, comprising of compact CPV system with cost effective but highly accurate solar tracking sensor and wireless master slave control. In addition, the performance of the developed CPV systems is evaluated for production of hydrogen, which can be used as energy carrier or energy storage and a maximum solar to hydrogen efficiency of 18% is obtained. However, due to dynamic nature of the weather data and throughout the day variations in the performance of CPV and electrolyser, the solar to hydrogen performance is proposed to be reported as daily and long term average efficiency. The CPV-Hydrogen system showed daily average conversion efficiency of 15%, with solar to hydrogen production rate of 218 kW h/kg.

Microbial production of hydrogen from starch-manufacturing wastes

Energy Technology Data Exchange (ETDEWEB)

Yokoi, H.; Maki, R.; Hirose, J.; Hayashi, S. [Miyazaki Univ. (Japan). Dept. of Applied Chemistry

2002-05-01

Effective hydrogen production from starch-manufacturing wastes by microorganisms was investigated. Continuous hydrogen production in high yield of 2.7 mol H{sub 2} mol{sup -1} glucose was attained by a mixed culture of Clostridium butyricum and Enterobacter aerogenes HO-39 in the starch waste medium consisting of sweet potato starch residue as a carbon source and corn steep liquor as a nitrogen source in a repeated batch culture. Rhodobacter sp. M-19 could produce hydrogen from the supernatant of the culture broth obtained in the repeated batch culture of C. butyricum and E. aerogenes HO-39. Hydrogen yield of 4.5 mol H{sub 2} mol{sup -1} glucose was obtained by culturing Rhodobacter sp. M-19 in the supernatant supplemented with 20{mu}gl{sup -1} Na{sub 2}MoO{sub 4} 2H{sub 2}O and 10mgl{sup -1} EDTA in a repeated batch culture with pH control at 7.5. Therefore, continuous hydrogen production with total hydrogen yield of 7.2 mol H{sub 2} mol{sup -1} glucose from the starch remaining in the starch residue was attained by the repeated batch culture with C. butyricum and E. aerogenes HO-39 and by the successive repeated batch culture with Rhodobacter sp. M-19. (Author)

Ovonic Renewable Hydrogen (ORH) - low temperature hydrogen production from renewable fuels

International Nuclear Information System (INIS)

Reichman, B.; Mays, W.; Strebe, J.; Fetcenko, M.

2009-01-01

'Full text': ECD has developed a new technology to produce hydrogen from various organic matters. In this technology termed Ovonic Renewable Hydrogen (ORH), base material such as NaOH is used as a reactant to facilitate the reforming of the organic matters to hydrogen gas. This Base-Facilitated Reforming (BFR) process is a one-step process and has number of advantages over the conventional steam reforming and gasification processes including lower operation temperature and lower heat consumption. This paper will describe the ORH process and discuss its technological and economics advantages over the conventional hydrogen production processes. ORH process has been studied and demonstrated on variety of renewable fuels including liquid biofuels and solid biomass materials. Results of these studies will be presented. (author)

Study on substrate metabolism process of saline waste sludge and its biological hydrogen production potential.

Science.gov (United States)

Zhang, Zengshuai; Guo, Liang; Li, Qianqian; Zhao, Yangguo; Gao, Mengchun; She, Zonglian

2017-07-01

With the increasing of high saline waste sludge production, the treatment and utilization of saline waste sludge attracted more and more attention. In this study, the biological hydrogen production from saline waste sludge after heating pretreatment was studied. The substrate metabolism process at different salinity condition was analyzed by the changes of soluble chemical oxygen demand (SCOD), carbohydrate and protein in extracellular polymeric substances (EPS), and dissolved organic matters (DOM). The excitation-emission matrix (EEM) with fluorescence regional integration (FRI) was also used to investigate the effect of salinity on EPS and DOM composition during hydrogen fermentation. The highest hydrogen yield of 23.6 mL H 2 /g VSS and hydrogen content of 77.6% were obtained at 0.0% salinity condition. The salinity could influence the hydrogen production and substrate metabolism of waste sludge.

Compact hydrogen production systems for solid polymer fuel cells

Science.gov (United States)

Ledjeff-Hey, K.; Formanski, V.; Kalk, Th.; Roes, J.

Generally there are several ways to produce hydrogen gas from carbonaceous fuels like natural gas, oil or alcohols. Most of these processes are designed for large-scale industrial production and are not suitable for a compact hydrogen production system (CHYPS) in the power range of 1 kW. In order to supply solid polymer fuel cells (SPFC) with hydrogen, a compact fuel processor is required for mobile applications. The produced hydrogen-rich gas has to have a low level of harmful impurities; in particular the carbon monoxide content has to be lower than 20 ppmv. Integrating the reaction step, the gas purification and the heat supply leads to small-scale hydrogen production systems. The steam reforming of methanol is feasible at copper catalysts in a low temperature range of 200-350°C. The combination of a small-scale methanol reformer and a metal membrane as purification step forms a compact system producing high-purity hydrogen. The generation of a SPFC hydrogen fuel gas can also be performed by thermal or catalytic cracking of liquid hydrocarbons such as propane. At a temperature of 900°C the decomposition of propane into carbon and hydrogen takes place. A fuel processor based on this simple concept produces a gas stream with a hydrogen content of more than 90 vol.% and without CO and CO2.

Solid oxide fuel cells and hydrogen production

International Nuclear Information System (INIS)

Dogan, F.

2009-01-01

'Full text': A single-chamber solid oxide fuel cell (SC-SOFC), operating in a mixture of fuel and oxidant gases, provides several advantages over the conventional SOFC such as simplified cell structure (no sealing required). SC-SOFC allows using a variety of fuels without carbon deposition by selecting appropriate electrode materials and cell operating conditions. The operating conditions of single chamber SOFC was studied using hydrocarbon-air gas mixtures for a cell composed of NiO-YSZ / YSZ / LSCF-Ag. The cell performance and catalytic activity of the anode was measured at various gas flow rates. The results showed that the open-circuit voltage and the power density increased as the gas flow rate increased. Relatively high power densities up to 660 mW/cm 2 were obtained in a SC-SOFC using porous YSZ electrolytes instead of dense electrolytes required for operation of a double chamber SOFC. In addition to propane- or methane-air mixtures as a fuel source, the cells were also tested in a double chamber configuration using hydrogen-air mixtures by controlling the hydrogen/air ratio at the cathode and the anode. Simulation of single chamber conditions in double chamber configurations allows distinguishing and better understanding of the electrode reactions in the presence of mixed gases. Recent research efforts; the effect of hydrogen-air mixtures as a fuel source on the performance of anode and cathode materials in single-chamber and double-chamber SOFC configurations,will be presented. The presentation will address a review on hydrogen production by utilizing of reversible SOFC systems. (author)

Feasibility of bio-hydrogen production from sewage sludge using defined microbial consortium

Energy Technology Data Exchange (ETDEWEB)

Shireen Meher Kotay; Debabrata Das [Fermentation Technology Lab., Department of Biotechnology, Indian Institute of Technology Kharagpur, W.B., INDIA-721302 (India)

2006-07-01

Biological hydrogen production potential of a defined microbial consortium consisting of three facultative anaerobes, Enterobacter cloacae IIT-BT 08, Citrobacter freundii IIT-BT L139 and Bacillus coagulans IIT-BT S1 was studied. In this investigation their individual and combinatorial H{sub 2} production capabilities have been studied on defined media and pretreated sewage sludge. Defined medium, MYG (1% w/v Malt extract, 0.4% w/v yeast extract and 1% w/v glucose) with glucose as limiting substrate has been found to be most suitable for hydrogen production. Individually E. cloacae clearly gave higher yield (276 ml H{sub 2}/ g COD reduced) using defined medium than the other two strains. There was no considerable difference in maximal yield of hydrogen from individual and combinatorial (1:1:1 consortium) modes suggesting that E. cloacae dominated in the consortia on defined medium. Contradictorily, B. coagulans gave better bio-hydrogen yield (37.16 ml H{sub 2}/g COD consumed) than the other two strains when activated sewage sludge was used as substrate. The pretreatment of sludge included sterilization, (15% v/v) dilution and supplementation with 0.5%w/v glucose which was found to be essential to screen out the hydrogen consuming bacteria and ameliorate the hydrogenation. Considering (1:1:1) consortium as inoculum, interestingly yield of hydrogen was recorded to increase to 41.23 ml H{sub 2}/ g COD reduced inferring that in consortium, the substrate utilization was significantly higher. The hydrogen yield from pretreated sludge obtained in this study (35.54 ml H{sub 2} g sludge) has been found to be distinctively higher than the earlier reports (8.1 - 16.9 ml H{sub 2}/g sludge). However it was lower compared to the yield obtained from co-digestion of (83:17) food waste and sewage sludge (122 ml H{sub 2}/g carbohydrate COD). Employing formulated microbial consortia for bio-hydrogen production from sewage sludge was an attempt to augment the hydrogen yield from sludge

Feasibility of bio-hydrogen production from sewage sludge using defined microbial consortium

Energy Technology Data Exchange (ETDEWEB)

Shireen Meher Kotay; Debabrata Das [Fermentation Technology Lab., Department of Biotechnology, Indian Institute of Technology Kharagpur, W.B., INDIA-721302 (India)

2006-07-01

Biological hydrogen production potential of a defined microbial consortium consisting of three facultative anaerobes, Enterobacter cloacae IIT-BT 08, Citrobacter freundii IIT-BT L139 and Bacillus coagulans IIT-BT S1 was studied. In this investigation their individual and combinatorial H{sub 2} production capabilities have been studied on defined media and pretreated sewage sludge. Defined medium, MYG (1% w/v Malt extract, 0.4% w/v yeast extract and 1% w/v glucose) with glucose as limiting substrate has been found to be most suitable for hydrogen production. Individually E. cloacae clearly gave higher yield (276 ml H{sub 2}/ g COD reduced) using defined medium than the other two strains. There was no considerable difference in maximal yield of hydrogen from individual and combinatorial (1:1:1 consortium) modes suggesting that E. cloacae dominated in the consortia on defined medium. Contradictorily, B. coagulans gave better bio-hydrogen yield (37.16 ml H{sub 2}/ g COD consumed) than the other two strains when activated sewage sludge was used as substrate. The pretreatment of sludge included sterilization, (15% v/v) dilution and supplementation with 0.5% w/v glucose which was found to be essential to screen out the hydrogen consuming bacteria and ameliorate the hydrogenation. Considering (1:1:1) consortium as inoculum, interestingly yield of hydrogen was recorded to increase to 41.23 ml H{sub 2}/ g COD reduced inferring that in consortium, the substrate utilization was significantly higher. The hydrogen yield from pretreated sludge obtained in this study (35.54 ml H{sub 2}/ g sludge) has been found to be distinctively higher than the earlier reports (8.1 - 16.9 ml H{sub 2} / g sludge). However it was lower compared to the yield obtained from co-digestion of (83:17) food waste and sewage sludge (122 ml H{sub 2}/ g carbohydrate COD). Employing formulated microbial consortia for bio-hydrogen production from sewage sludge was an attempt to augment the hydrogen yield from

Feasibility of bio-hydrogen production from sewage sludge using defined microbial consortium

International Nuclear Information System (INIS)

Shireen Meher Kotay; Debabrata Das

2006-01-01

Biological hydrogen production potential of a defined microbial consortium consisting of three facultative anaerobes, Enterobacter cloacae IIT-BT 08, Citrobacter freundii IIT-BT L139 and Bacillus coagulans IIT-BT S1 was studied. In this investigation their individual and combinatorial H 2 production capabilities have been studied on defined media and pretreated sewage sludge. Defined medium, MYG (1% w/v Malt extract, 0.4% w/v yeast extract and 1% w/v glucose) with glucose as limiting substrate has been found to be most suitable for hydrogen production. Individually E. cloacae clearly gave higher yield (276 ml H 2 / g COD reduced) using defined medium than the other two strains. There was no considerable difference in maximal yield of hydrogen from individual and combinatorial (1:1:1 consortium) modes suggesting that E. cloacae dominated in the consortia on defined medium. Contradictorily, B. coagulans gave better bio-hydrogen yield (37.16 ml H 2 /g COD consumed) than the other two strains when activated sewage sludge was used as substrate. The pretreatment of sludge included sterilization, (15% v/v) dilution and supplementation with 0.5%w/v glucose which was found to be essential to screen out the hydrogen consuming bacteria and ameliorate the hydrogenation. Considering (1:1:1) consortium as inoculum, interestingly yield of hydrogen was recorded to increase to 41.23 ml H 2 / g COD reduced inferring that in consortium, the substrate utilization was significantly higher. The hydrogen yield from pretreated sludge obtained in this study (35.54 ml H 2 g sludge) has been found to be distinctively higher than the earlier reports (8.1 - 16.9 ml H 2 /g sludge). However it was lower compared to the yield obtained from co-digestion of (83:17) food waste and sewage sludge (122 ml H 2 /g carbohydrate COD). Employing formulated microbial consortia for bio-hydrogen production from sewage sludge was an attempt to augment the hydrogen yield from sludge. (authors)

Feasibility of bio-hydrogen production from sewage sludge using defined microbial consortium

International Nuclear Information System (INIS)

Shireen Meher Kotay; Debabrata Das

2006-01-01

Biological hydrogen production potential of a defined microbial consortium consisting of three facultative anaerobes, Enterobacter cloacae IIT-BT 08, Citrobacter freundii IIT-BT L139 and Bacillus coagulans IIT-BT S1 was studied. In this investigation their individual and combinatorial H 2 production capabilities have been studied on defined media and pretreated sewage sludge. Defined medium, MYG (1% w/v Malt extract, 0.4% w/v yeast extract and 1% w/v glucose) with glucose as limiting substrate has been found to be most suitable for hydrogen production. Individually E. cloacae clearly gave higher yield (276 ml H 2 / g COD reduced) using defined medium than the other two strains. There was no considerable difference in maximal yield of hydrogen from individual and combinatorial (1:1:1 consortium) modes suggesting that E. cloacae dominated in the consortia on defined medium. Contradictorily, B. coagulans gave better bio-hydrogen yield (37.16 ml H 2 / g COD consumed) than the other two strains when activated sewage sludge was used as substrate. The pretreatment of sludge included sterilization, (15% v/v) dilution and supplementation with 0.5% w/v glucose which was found to be essential to screen out the hydrogen consuming bacteria and ameliorate the hydrogenation. Considering (1:1:1) consortium as inoculum, interestingly yield of hydrogen was recorded to increase to 41.23 ml H 2 / g COD reduced inferring that in consortium, the substrate utilization was significantly higher. The hydrogen yield from pretreated sludge obtained in this study (35.54 ml H 2 / g sludge) has been found to be distinctively higher than the earlier reports (8.1 - 16.9 ml H 2 / g sludge). However it was lower compared to the yield obtained from co-digestion of (83:17) food waste and sewage sludge (122 ml H 2 / g carbohydrate COD). Employing formulated microbial consortia for bio-hydrogen production from sewage sludge was an attempt to augment the hydrogen yield from sludge. (authors)

Study of organic waste for production of hydrogen in reactor

International Nuclear Information System (INIS)

Guzmán Chinea, Jesús Manuel; Guzmán Marrero, Elizabeth; Pérez Ponce, Alejandro

2015-01-01

Biological processes have long been used for the treatment of organic waste makes, especially our study is based on the anaerobic process in reactors, using residual organic industry. Without excluding other non-industrial we have studied. Fundamental objectives treating organic waste is to reduce the pollutant load to the environment, another aim is to recover the waste recovering the energy contained in it. In this context, the biological hydrogen production from organic waste is an interesting alternative because it has low operating costs and raw material is being used as a residue in any way should be treated before final disposal. Hydrogen can be produced sustainable by anaerobic bacteria that grow in the dark with rich carbohydrate substrates giving as final products H 2 , CO 2 and volatile fatty acids. The whey byproduct from cheese production, has great potential to be used for the generation of hydrogen as it has a high carbohydrate content and a high organic load. The main advantages of using anaerobic processes in biological treatment of organic waste, are the low operating costs, low power consumption, the ability to degrade high organic loads, resistance biomass to stay long in the absence of substrate, without lose their metabolic activity, and low nutritional requirements and increase the performance of 0.9 mol H2 / mol lactose. (full text)Biological processes have long been used for the treatment of organic waste makes, especially our study is based on the anaerobic process in reactors, using residual organic industry. Without excluding other non-industrial we have studied. Fundamental objectives treating organic waste is to reduce the pollutant load to the environment, another aim is to recover the waste recovering the energy contained in it. In this context, the biological hydrogen production from organic waste is an interesting alternative because it has low operating costs and raw material is being used as a residue in any way should be treated

Hydrogen production and storage: R & D priorities and gaps

Energy Technology Data Exchange (ETDEWEB)

NONE

2006-05-04

This review of priorities and gaps in hydrogen production and storage R & D has been prepared by the IEA Hydrogen Implementing Agreement in the context of the activities of the IEA Hydrogen Co-ordination Group. It includes two papers. The first is by Trygve Riis, Elisabet F. Hagen, Preben J.S. Vie and Oeystein Ulleberg. This offers an overview of the technologies for hydrogen production. The technologies discussed are reforming of natural gas; gasification of coal and biomass; and the splitting of water by water-electrolysis, photo-electrolysis, photo-biological production and high-temperature decomposition. The second paper is by Trygve Riis, Gary Sandrock, Oeystein Ulleberg and Preben J.S. Vie. The objective of this paper is to provide a brief overview of the possible hydrogen storage options available today and in the foreseeable future. Hydrogen storage can be considered for onboard vehicular, portable, stationary, bulk, and transport applications, but the main focus of this paper is on vehicular storage, namely fuel cell or ICE/electric hybrid vehicles. 7 refs., 24 figs., 14 tabs.

Effect of light intensity and initial pH during hydrogen production by an integrated dark and photofermentation process

Energy Technology Data Exchange (ETDEWEB)

Nath, Kaushik [Department of Chemical Engineering, GH Patel College of Engineering and Technology, Vallabh Vidyanagar 388 120, Gujarat (India); Das, Debabrata [Fermentation Technology Laboratory, Department of Biotechnology, Indian Institute of Technology, Kharagpur 721302 (India)

2009-09-15

Photofermentation was carried out with the spent fermentation broth obtained from the anaerobic dark fermentation in a two-stage process. For the first stage, i.e. dark fermentation Enterobacter cloacae DM 11 was used as hydrogen producing microorganism. For photofermentation Rhodobacter sphaeroides O.U. 001, a photo-heterotrophic purple non-sulfur bacterium, was used. pH study revealed that cumulative hydrogen production was maximum at initial medium pH of 7.0 {+-} 0.2. Biomass yield was also high at the vicinity of pH 7.0 and it decreased as the pH increased from 7.0 to 8.0. Increased light intensity resulted in an increase in the total volume of hydrogen evolved and also hydrogen production rate. However, light conversion efficiency decreased by increasing light intensity. A four-fold increase in light intensity resulted in a three-fold decrease in light conversion efficiency although the cumulative volume of hydrogen gas production increased. It was observed that only a maximum of 0.51% light conversion efficiency could be achieved but at the expense of very low light intensity of 2500 lux (3.75 W m{sup -2}). (author)

Developments and constraints in fermentative hydrogen production

NARCIS (Netherlands)

Bartacek, J.; Zabranska, J.; Lens, P.N.L.

2007-01-01

Fermentative hydrogen production is a novel aspect of anaerobic digestion. The main advantage of hydrogen is that it is a clean and renewable energy source/carrier with high specific heat of combustion and no contribution to the Greenhouse effect, and can be used in many industrial applications.

Renewable hydrogen production by catalytic steam reforming of peanut shells pyrolysis products

Energy Technology Data Exchange (ETDEWEB)

Evans, R.J.; Chornet, E.; Czernik, S.; Feik, C.; French, R.; Phillips, S. [National Renewable Energy Lab., Golden, CO (United States); Abedi, J.; Yeboah, Y.D. [Clark Atlanta Univ., Atlanta, GA (United States); Day, D.; Howard, J. [Scientific Carbons Inc., Blakely, GA (United States); McGee, D. [Enviro-Tech Enterprises Inc., Matthews, NC (United States); Realff, M.J. [Georgia Inst. of Technology, Atlanta, GA (United States)

2002-07-01

A project was initiated to determine the feasibility of producing hydrogen from agricultural wastes at a cost comparable to methane-reforming technologies. It is possible that hydrogen can be produced cost competitively with natural gas reforming by integrating hydrogen production with existing waste product utilization processes. This report presents initial results of an engineering demonstration project involving the development of a steam reforming process by a team of government, industrial and academic organizations working at the thermochemical facility at the National Renewable Energy Laboratory. The process is to be used on the gaseous byproducts from a process for making activated carbon from densified peanut shells. The reactor is interfaced with a 20 kg/hour fluidized-bed fast pyrolysis system and takes advantage of process chemical analysis and computer control and monitoring capacity. The reactor will be tested on the pyrolysis vapors produced in the activated carbon process. The final phase of the project will look at the production of hydrogen through the conversion of residual CO to H{sub 2} over a shift catalyst and separating hydrogen from CO{sub 2} using pressure swing adsorption. The purified oxygen will be mixed with natural gas and used for transportation purposes. The study demonstrates the potential impact of hydrogen and bioenergy on the economic development and diversification of rural areas. 11 refs., 2 tabs., 5 figs.

Principle and perspectives of hydrogen production through biocatalyzed electrolysis

NARCIS (Netherlands)

Rozendal, R.A.; Hamelers, H.V.M.; Euverink, G.J.W.; Metz, S.J.; Buisman, C.J.N.

2006-01-01

Biocatalyzed electrolysis is a novel biological hydrogen production process with the potential to efficiently convert a wide range of dissolved organic materials in wastewaters. Even substrates formerly regarded to be unsuitable for hydrogen production due to the endothermic nature of the involved

A CFD Simulation of Hydrogen Production in Microreactors

Directory of Open Access Journals (Sweden)

Javad Sabziani

2015-01-01

Full Text Available In this study, the modeling of hydrogen production process in microreactors by methanol-steam reforming reaction is investigated. The catalytic reaction of methanol-steam reforming producing hydrogen is simulated considering a 3D geometry for the microreactor. To calculate diffusion among species, mixture average correlations are compared to Stephan-Maxwell equations. The reactions occurring inside the microreactor include reforming of methanol with steam, methanol decomposition, and a reaction between carbon dioxide and hydrogen. The main objectives of this study are the prediction of temperature profile along the microreactor using either mixture average method or Stephan-Maxwell one and the comparison between the present predictions and some existing experimental data. The simulation results indicate that Stephan-Maxwell method conforms more suitably to the experimental results. The difference is more at lower feed flow rates since, when the flow rate increases, mass transfer mechanism changes from diffusion to convection, which in turn reduces the difference.

Biological Hydrogen Production: Simultaneous Saccharification and Fermentation with Nitrogen and Phosphorus Removal from Wastewater Effluent

Science.gov (United States)

2012-03-01

process.7 The reaction is of great economic importance given that the world’s industrial production of nitrogenous fertilizer increased 27-fold between... Enzymatic Saccharification and Fermentation of Paper and Pulp Industry Effluent for Biohydrogen Production . Int. J. Hydrogen Energy 2010, 35, pp...Reactor Setup and Operation 11 4.2 Operational Comparison: SBR and CBR 12 4.3 Effect of pH and Loading on Hydrogen Production 13 4.4 Enzymatic Source

Composition of hydrogenation products of Borodino brown coal

Energy Technology Data Exchange (ETDEWEB)

M.A. Gyul' malieva; A.S. Maloletnev; G.A. Kalabin; A.M. Gyul' maliev [Institute for Fossil Fuels, Moscow (Russian Federation)

2008-02-15

The composition of liquid products of hydrogenation of brown coal from the Borodino deposit was determined by means of {sup 13}C NMR spectroscopy and chemical thermodynamics methods. It was shown that the group composition of the liquid hydrogenation products at thermodynamic equilibrium is predictable from the elemental composition of the organic matter of parent coal. 9 refs., 5 figs., 6 tabs.

Hydrogen Production Cost Estimate Using Biomass Gasification: Independent Review

Energy Technology Data Exchange (ETDEWEB)

Ruth, M.

2011-10-01

This independent review is the conclusion arrived at from data collection, document reviews, interviews and deliberation from December 2010 through April 2011 and the technical potential of Hydrogen Production Cost Estimate Using Biomass Gasification. The Panel reviewed the current H2A case (Version 2.12, Case 01D) for hydrogen production via biomass gasification and identified four principal components of hydrogen levelized cost: CapEx; feedstock costs; project financing structure; efficiency/hydrogen yield. The panel reexamined the assumptions around these components and arrived at new estimates and approaches that better reflect the current technology and business environments.

Hydrogen - High pressure production and storage

International Nuclear Information System (INIS)

Lauretta, J.R

2005-01-01

The development of simple, safe and more and more efficient technologies for the production and the storage of hydrogen is necessary condition for the transition towards the economy of hydrogen.In this work the hydrogen production studies experimentally to high pressure by electrolysis of alkaline solutions without the intervention of compressing systems and its direct storage in safe containers.The made tests show that the process of electrolysis to high pressure is feasible and has better yield than to low pressure, and that is possible to solve the operation problems, with relatively simple technology.The preliminary studies and tests indicate that the system container that studied is immune to the outbreak and can have forms and very different sizes, nevertheless, to reach or to surpass the efficiency of storage of the conventional systems the investments necessary will be due to make to be able to produce aluminum alloy tubes of high resistance

Influence of temperature on hydrogen production from bread mill wastewater by sewage sludge

Energy Technology Data Exchange (ETDEWEB)

Tang, G.L.; Huang, J.; Li, Y.Y.; Sun, Z.J. [China Agricultural Univ., Beijing (China). College of Resources and Environmental Sciences; Tang, Q.Q. [Nanjing Univ., Nanjing (China). Medical School

2008-07-01

Hydrogen (H{sub 2}) energy has been touted as a sustainable and clean energy source that can solve environmental problems such as acid rain, greenhouse gases and transboundary pollution. While most hydrogen is currently produced from nonrenewable sources such as oil, natural gas, and coal, these processes are energy-intensive and costly. The biological production of hydrogen using fermentative bacteria is an environmentally friendly and energy-saving process which has recently attracted much attention as an effective way of converting biomass into H{sub 2}. Waste-based H{sub 2} production processes mainly include wastewater from paper mills, municipal solid waste, rice winery wastewater, and food wastewater from cafeterias. This study investigated the use of bread mill wastewater for biological production of hydrogen due to its high production potential. Annual bread production in China is estimated to be over 1.5 million tons, producing 10 m{sup 3} of wastewater per ton of bread. The wastewater has high chemical oxygen demand and carbohydrate concentrations and is therefore suitable for anaerobic treatment processes. This study evaluated the effect of temperature on H{sub 2} production from bread mill wastewater by sewage sludge in lab-scale experiments. H{sub 2} production, the distribution of volatile fatty acids and the lag-phase time were influenced by temperature. H{sub 2} production and H{sub 2} yield increased with increasing temperature. The optimal temperature for H{sub 2} production was 50 degrees C. Butyrate, acetate and alcohol were the main by-products of H{sub 2} fermentation. According to 16S rDNA analysis, the dominant microflora was Clostridium, but the microbial species varied with temperature. The activation energy for H{sub 2} production was estimated to be 92 kJ per mol for bread mill wastewater. It was concluded that bread mill wastewater could potentially serve as a substrate for H{sub 2} production. This research provides a means of

High temperature electrolysis for hydrogen production using nuclear energy

International Nuclear Information System (INIS)

Herring, J. Stephen; O'brien, James E.; Stoots, Carl M.; Hawkes, Grant L.; Hartvigsen, Joseph J.

2005-01-01

High-temperature nuclear reactors have the potential for substantially increasing the efficiency of hydrogen production from water splitting, which can be accomplished via high-temperature electrolysis (HTE) or thermochemical processes. In order to achieve competitive efficiencies, both processes require high-temperature operation (∼850degC). High-temperature electrolytic water splitting supported by nuclear process heat and electricity has the potential to produce hydrogen with overall system efficiencies of 45 to 55%. At the Idaho National Laboratory, we are developing solid-oxide cells to operate in the steam electrolysis mode. The research program includes both experimental and modeling activities. Experimental results were obtained from ten-cell and 22-cell planar electrolysis stacks, fabricated by Ceramatec, Inc. The electrolysis cells are electrolyte-supported, with scandia-stabilized zirconia electrolytes (∼200 μm thick, 64 cm 2 active area), nickel-cermet steam/hydrogen electrodes, and manganite air-side electrodes. The metallic interconnect plates are fabricated from ferritic stainless steel. The experiments were performed over a range of steam inlet mole fractions, gas glow rates, and current densities. Hydrogen production rates greater than 100 normal liters per hour for 196 hours have been demonstrated. In order to evaluate the performance of large-scale HTE operations, we have developed single-cell models, based on FLUENT, and a process model, using the systems-analysis code HYSYS. (author)

Improvement of anaerobic bio-hydrogen gas production from organic sludge waste

International Nuclear Information System (INIS)

Lee, S.; Lee, Y. H.

2009-01-01

Microbial hydrogen gas production from organic matters stands out as one of the most promising alternatives for sustainable green energy production. Based on the literature review, investigation of anaerobic bio-hydrogen gas production from organic sludge waste using a mixed culture has been very limited. The objective of this study was to assess the anaerobic bio-hydrogen gas production from organic sludge waste under various conditions. (Author)

Potential of biogenic hydrogen production for hydrogen driven remediation strategies in marine environments.

Science.gov (United States)

Hosseinkhani, Baharak; Hennebel, Tom; Boon, Nico

2014-09-25

Fermentative production of bio-hydrogen (bio-H2) from organic residues has emerged as a promising alternative for providing the required electron source for hydrogen driven remediation strategies. Unlike the widely used production of H2 by bacteria in fresh water systems, few reports are available regarding the generation of biogenic H2 and optimisation processes in marine systems. The present research aims to optimise the capability of an indigenous marine bacterium for the production of bio-H2 in marine environments and subsequently develop this process for hydrogen driven remediation strategies. Fermentative conversion of organics in marine media to H2 using a marine isolate, Pseudoalteromonas sp. BH11, was determined. A Taguchi design of experimental methodology was employed to evaluate the optimal nutritional composition in batch tests to improve bio-H2 yields. Further optimisation experiments showed that alginate-immobilised bacterial cells were able to produce bio-H2 at the same rate as suspended cells over a period of several weeks. Finally, bio-H2 was used as electron donor to successfully dehalogenate trichloroethylene (TCE) using biogenic palladium nanoparticles as a catalyst. Fermentative production of bio-H2 can be a promising technique for concomitant generation of an electron source for hydrogen driven remediation strategies and treatment of organic residue in marine ecosystems. Copyright © 2014 Elsevier B.V. All rights reserved.

Cleaning up gasoline will increase refinery hydrogen demand

International Nuclear Information System (INIS)

Pretorius, E.B.; Muan, A.

1992-01-01

This paper reports that hydrogen needs will increase two to five times as the world turns its attention to cleaning up engine exhaust. The subject of fuel trends and hydrogen needs at Foster Wheeler USA Corp.'s Hydrogen Plant Conference, June 2--4, in Orlando was addressed. The conference was attended by more than 100 people from 12 different countries. Drawing on knowledge from over 1 billion scfd of total installed hydrogen plant capacity, Foster Wheeler experts presented papers in the fields of steam reforming, partial oxidation (with all feedstocks, from natural gas to resids and coal), and steam reformer design. Other industry specialists gave papers on refinery balances, markets, coal feedstocks, utility systems, and components for hydrogen plants

Hydrogenation of rapeseed oil for production of liquid bio-chemicals

International Nuclear Information System (INIS)

Pinto, F.; Martins, S.; Gonçalves, M.; Costa, P.; Gulyurtlu, I.; Alves, A.; Mendes, B.

2013-01-01

Highlights: ► Production of renewable liquid hydrocarbons through rapeseed oil hydrogenation. ► Hydrogenation at lower temperature and lower hydrogen pressures. ► Test of a catalyst commonly employed in petrochemical industry. ► Improve of hydrogenation process viability by decreasing operational costs. ► Analysis of hydrogenated product applications as bio-chemicals. -- Abstract: The main objective of rapeseed oil hydrogenation tests was the production of liquid bio-chemicals to be used as renewable raw material for the production of several chemicals and in chemical synthesis to substitute petroleum derived stuff. As, hydrogenation of vegetable oils is already applied for the production of biofuels, the work done focused in producing aromatic compounds, due to their economic value. The effect of experimental conditions on rapeseed oil hydrogenation was studied, namely, reaction temperature and time with the aim of selecting the most favourable conditions to convert rapeseed oil into liquid valuable bio-chemicals. Rapeseed oil was hydrogenated at a hydrogen initial pressure of 1.10 MPa. Reaction temperature varied in the range from 200 °C to 400 °C, while reaction times between 6 and 180 min were tested. The performance of a commercial cobalt and molybdenum catalyst was also studied. The highest hydrocarbons yields were obtained at the highest temperature and reaction times tested. At a temperature of 400 °C and at the reaction time of 120 min hydrocarbons yield was about 92% in catalyst presence, while in the absence of the catalyst this value decreased to 85%. Hydrocarbons yield was even higher when the reaction time of 180 min was used in the presence of catalyst, as the yield of 97% was observed. At these conditions hydrocarbons formed had a high content of aromatic compounds, around 50%. For this reason, the viscosity values of hydrogenated oils were lower than that established by EN590, which together with hydrogenated liquids composition

Enhanced Hydrogen Production Integrated with CO2 Separation in a Single-Stage Reactor

Energy Technology Data Exchange (ETDEWEB)

Shwetha Ramkumar; Mahesh Iyer; Danny Wong; Himanshu Gupta; Bartev Sakadjian; Liang-Lhih Fan

2008-09-30

High purity hydrogen is commercially produced from syngas by the Water Gas Shift Reaction (WGSR) in high and low temperature shift reactors using iron oxide and copper catalysts respectively. However, the WGSR is thermodynamically limited at high temperatures towards hydrogen production necessitating excess steam addition and catalytic operation. In the calcium looping process, the equilibrium limited WGSR is driven forward by the incessant removal of CO{sub 2} by-product through the carbonation of calcium oxide. At high pressures, this process obviates the need for a catalyst and excess steam requirement, thereby removing the costs related to the procurement and deactivation of the catalyst and steam generation. Thermodynamic analysis for the combined WGS and carbonation reaction was conducted. The combined WGS and carbonation reaction was investigated at varying pressures, temperatures and S/C ratios using a bench scale reactor system. It was found that the purity of hydrogen increases with the increase in pressure and at a pressure of 300 psig, almost 100% hydrogen is produced. It was also found that at high pressures, high purity hydrogen can be produced using stoichiometric quantities of steam. On comparing the catalytic and non catalytic modes of operation in the presence of calcium oxide, it was found that there was no difference in the purity of hydrogen produced at elevated pressures. Multicyclic reaction and regeneration experiments were also conducted and it was found that the purity of hydrogen remains almost constant after a few cycles.

Life cycle assessment of hydrogen production and fuel cell systems

International Nuclear Information System (INIS)

Dincer, I.

2007-01-01

This paper details life cycle assessment (LCA) of hydrogen production and fuel cell system. LCA is a key tool in hydrogen and fuel cell technologies for design, analysis, development; manufacture, applications etc. Energy efficiencies and greenhouse gases and air pollution emissions have been evaluated in all process steps including crude oil and natural gas pipeline transportation, crude oil distillation, natural gas reprocessing, wind and solar electricity generation , hydrogen production through water electrolysis and gasoline and hydrogen distribution and utilization

Hydrogen production from fusion reactors coupled with high temperature electrolysis

International Nuclear Information System (INIS)

Fillo, J.A.; Powell, J.R.; Steinberg, M.

The decreasing availability of fossil fuels emphasizes the need to develop systems which will produce synthetic fuel to substitute for and complement the natural supply. An important first step in the synthesis of liquid and gaseous fuels is the production of hydrogen. Thermonuclear fusion offers an inexhaustible source of energy for the production of hydrogen from water. Processes which may be considered for this purpose include electrolysis, thermochemical decomposition or thermochemical-electrochemical hybrid cycles. Preliminary studies at Brookhaven indicate that high temperature electrolysis has the highest potential efficiency for production of hydrogen from fusion. Depending on design electric generation efficiencies of approximately 40 to 60 percent and hydrogen production efficiencies of approximately 50 to 70 percent are projected for fusion reactors using high temperature blankets

Use of coffee mucilage as a new substrate for hydrogen production in anaerobic co-digestion with swine manure.

Science.gov (United States)

Hernández, Mario Andrés; Rodríguez Susa, Manuel; Andres, Yves

2014-09-01

Coffee mucilage (CM), a novel substrate produced as waste from agricultural activity in Colombia, the largest fourth coffee producer in the world, was used for hydrogen production. The study evaluated three ratios (C1-3) for co-digestion of CM and swine manure (SM), and an increase in organic load to improve hydrogen production (C4). The hydrogen production was improved by a C/N ratio of 53.4 used in C2 and C4. The average hydrogen production rate in C4 was 7.6 NL H2/LCMd, which indicates a high hydrogen potential compare to substrates such as POME and wheat starch. In this condition, the biogas composition was 0.1%, 50.6% and 39.0% of methane, carbon dioxide and hydrogen, respectively. The butyric and acetic fermentation pathways were the main routes identified during hydrogen production which kept a Bu/Ac ratio at around 1.0. A direct relationship between coffee mucilage, biogas and cumulative hydrogen volume was established. Copyright © 2014 Elsevier Ltd. All rights reserved.

Nano-ferrites for water splitting: Unprecedented high photocatalytic hydrogen production under visible light

KAUST Repository

Mangrulkar, Priti A.; Polshettiwar, Vivek; Labhsetwar, Nitin K.; Varma, Rajender S.; Rayalu, Sadhana Suresh

2012-01-01

In the present investigation, hydrogen production via water splitting by nano-ferrites was studied using ethanol as the sacrificial donor and Pt as co-catalyst. Nano-ferrite is emerging as a promising photocatalyst with a hydrogen evolution rate of 8.275 μmol h -1 and a hydrogen yield of 8275 μmol h -1 g -1 under visible light compared to 0.0046 μmol h -1 for commercial iron oxide (tested under similar experimental conditions). Nano-ferrites were tested in three different photoreactor configurations. The rate of hydrogen evolution by nano-ferrite was significantly influenced by the photoreactor configuration. Altering the reactor configuration led to sevenfold (59.55 μmol h -1) increase in the hydrogen evolution rate. Nano-ferrites have shown remarkable stability in hydrogen production up to 30 h and the cumulative hydrogen evolution rate was observed to be 98.79 μmol h -1. The hydrogen yield was seen to be influenced by several factors like photocatalyst dose, illumination intensity, irradiation time, sacrificial donor and presence of co-catalyst. These were then investigated in detail. It was evident from the experimental data that nano-ferrites under optimized reaction conditions and photoreactor configuration could lead to remarkable hydrogen evolution activity under visible light. Temperature had a significant role in enhancing the hydrogen yield. © 2012 The Royal Society of Chemistry.

Method for the enzymatic production of hydrogen

Science.gov (United States)

Woodward, J.; Mattingly, S.M.

1999-08-24

The present invention is an enzymatic method for producing hydrogen comprising the steps of: (a) forming a reaction mixture within a reaction vessel comprising a substrate capable of undergoing oxidation within a catabolic reaction, such as glucose, galactose, xylose, mannose, sucrose, lactose, cellulose, xylan and starch; the reaction mixture also comprising an amount of glucose dehydrogenase in an amount sufficient to catalyze the oxidation of the substrate, an amount of hydrogenase sufficient to catalyze an electron-requiring reaction wherein a stoichiometric yield of hydrogen is produced, an amount of pH buffer in an amount sufficient to provide an environment that allows the hydrogenase and the glucose dehydrogenase to retain sufficient activity for the production of hydrogen to occur and also comprising an amount of nicotinamide adenine dinucleotide phosphate sufficient to transfer electrons from the catabolic reaction to the electron-requiring reaction; (b) heating the reaction mixture at a temperature sufficient for glucose dehydrogenase and the hydrogenase to retain sufficient activity and sufficient for the production of hydrogen to occur, and heating for a period of time that continues until the hydrogen is no longer produced by the reaction mixture, wherein the catabolic reaction and the electron-requiring reactions have rates of reaction dependent upon the temperature; and (c) detecting the hydrogen produced from the reaction mixture. 8 figs.

Hydrogen production from algal biomass - Advances, challenges and prospects.

Science.gov (United States)

Show, Kuan-Yeow; Yan, Yuegen; Ling, Ming; Ye, Guoxiang; Li, Ting; Lee, Duu-Jong

2018-06-01

Extensive effort is being made to explore renewable energy in replacing fossil fuels. Biohydrogen is a promising future fuel because of its clean and high energy content. A challenging issue in establishing hydrogen economy is sustainability. Biohydrogen has the potential for renewable biofuel, and could replace current hydrogen production through fossil fuel thermo-chemical processes. A promising source of biohydrogen is conversion from algal biomass, which is abundant, clean and renewable. Unlike other well-developed biofuels such as bioethanol and biodiesel, production of hydrogen from algal biomass is still in the early stage of development. There are a variety of technologies for algal hydrogen production, and some laboratory- and pilot-scale systems have demonstrated a good potential for full-scale implementation. This work presents an elucidation on development in biohydrogen encompassing biological pathways, bioreactor designs and operation and techno-economic evaluation. Challenges and prospects of biohydrogen production are also outlined. Copyright © 2018 Elsevier Ltd. All rights reserved.

Safety assessment for the IS process in a hydrogen production facility

International Nuclear Information System (INIS)

Cho, Nam Chul

2005-08-01

A substitute energy development have been required due to the dry up of the fossil fuel and an environmental problem. Consequently, among substitute energy to be discussed, producing hydrogen from water which does not release carbon is a very promising technology. Also, Iodine-Sulfur(IS) thermochemical water decomposition is one of the promising process which is used to produce hydrogen efficiently using the high temperature gas-cooled reactor(HTGR) as an energy source that is possible to supply heat over 1000 .deg. C. In this study, to make a safety assessment of the hydrogen production using the IS process, an initiating events analysis and an accident scenario modeling considering the relief system were carried out. A method for initiating event identification used the Master Logic Diagram(MLD) that is logical and deductive. As a result, 9 initiating events that cause a leakage of the chemical material were identified. 6 accident scenario based on the initiating event are identified and quantified to the event trees. The frequency of the chemical material leakage produced by IS process is estimated relatively high to the value of 1.22x10 -4 /y. Therefore, it requires more effort on safety of the hydrogen production which can be considered as a part of the nuclear system and safety management research to increase social acceptability. Moreover, these methods will be helpful to the safety assessment of the hydrogen production system of the IS process in general

Redox Control and Hydrogen Production in Sediment Caps Using Carbon Cloth Electrodes

Science.gov (United States)

Sun, Mei; Yan, Fei; Zhang, Ruiling; Reible, Danny D.; Lowry, Gregory V.; Gregory, Kelvin B.

2010-01-01

Sediment caps that degrade contaminants can improve their ability to contain contaminants relative to sand and sorbent-amended caps, but few methods to enhance contaminant degradation in sediment caps are available. The objective of this study was to determine if, carbon electrodes emplaced within a sediment cap at poised potential could create a redox gradient and provide electron donor for the potential degradation of contaminants. In a simulated sediment cap overlying sediment from the Anacostia River (Washington, DC), electrochemically induced redox gradients were developed within 3 days and maintained over the period of the test (~100 days). Hydrogen and oxygen were produced by water electrolysis at the electrode surfaces and may serve as electron donor and acceptor for contaminant degradation. Electrochemical and geochemical factors that may influence hydrogen production were studied. Hydrogen production displayed zero order kinetics with ~75% coulombic efficiency and rates were proportional to the applied potential between 2.5V to 5V and not greatly affected by pH. Hydrogen production was promoted by increasing ionic strength and in the presence of natural organic matter. Graphite electrode-stimulated degradation of tetrachlorobenzene in a batch reactor was dependent on applied voltage and production of hydrogen to a concentration above the threshold for biological dechlorination. These findings suggest that electrochemical reactive capping can potentially be used to create “reactive” sediments caps capable of promoting chemical or biological transformations of contaminants within the cap. PMID:20879761

Potential Fusion Market for Hydrogen Production Under Environmental Constraints

International Nuclear Information System (INIS)

Konishi, Satoshi

2005-01-01

Potential future hydrogen market and possible applications of fusion were analyzed. Hydrogen is expected as a major energy and fuel mediun for the future, and various processes for hydrogen production can be considered as candidates for the use of fusion energy. In order to significantly contribute to reduction of CO 2 emission, fusion must be deployed in developing countries, and must substitute fossil based energy with synthetic fuel such as hydrogen. Hydrogen production processes will have to evaluated and compared from the aspects of energy efficiency and CO 2 emission. Fusion can provide high temperature heat that is suitable for vapor electrolysis, thermo-chemical water decomposition and steam reforming with biomass waste. That is a possible advantage of fusion over renewables and Light water power reactor. Despite of its technical difficulty, fusion is also expected to have less limitation for siting location in the developing countries. Under environmental constraints, fusion has a chance to be a major primary energy source, and production of hydrogen enhances its contribution, while in 'business as usual', fusion will not be selected in the market. Thus if fusion is to be largely used in the future, meeting socio-economic requirements would be important

Effect of some environmental parameters on fermentative hydrogen production by Enterobacter cloacae DM11

Energy Technology Data Exchange (ETDEWEB)

Nath, K.; Kumar, A.; Das, D. [Indian Inst. of Technology, Kharagpur (India). Dept. of Biotechnology, Fermentation Technology Laboratory

2006-06-15

This study addressed the issue of using biological systems for hydrogen production as an environmentally sound alternative to conventional thermochemical and electrochemical processes. In particular, it examined the potential for anaerobic fermentation for biological hydrogen production and the possibility of coupling gaseous energy generation with simultaneous treatment of biodegradable waste materials. The study focused on hydrogen production by anaerobic fermentation using Enterobacter cloacae DM11, a Gram-negative, motile facultative anaerobe. Although hydrogen production by these bacteria depends on many environmental parameters, there is very little information on the effects of these factors in the hydrogen production potential of this organism. For that reason, this study examined the effect of initial medium pH, reaction temperature, initial glucose concentration, and iron (Fe2+) concentration on the fermentative production of hydrogen. Fermentative hydrogen production was carried out by Enterobacter cloacae DM11, using glucose as the substrate. Batch cultivations were performed in a 500 ml custom-designed vertical tubular bioreactor. The maximum molar yield of hydrogen was 3.31 mol (mol glucose){sub 1}. The rate and cumulative volume of hydrogen production decreased at higher initial glucose concentration. The pH of 6.5 at a temperature of 37 degrees C was most suitable for maximum rate of production of hydrogen in batch fermentation. The addition of Fe2+ on hydrogen production had a marginal enhancing effect on total hydrogen production. A simple model developed from the modified Gompertz equation was used to fit the cumulative hydrogen production curve and to estimate the hydrogen production potential, maximum production rate, and lag time. It was concluded that these study results could be used in the development of a high rate continuous hydrogen production process. 30 refs., 4 tabs., 3 figs.

40 CFR 415.420 - Applicability; description of the hydrogen cyanide production subcategory.

Science.gov (United States)

2010-07-01

... hydrogen cyanide production subcategory. 415.420 Section 415.420 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Hydrogen Cyanide Production Subcategory § 415.420 Applicability; description of the hydrogen cyanide production subcategory. This subpart applies to discharges to waters of the United States...

Economics and synergies of electrolytic and thermochemical methods of environmentally benign hydrogen production

International Nuclear Information System (INIS)

Naterer, G.F.

2010-01-01

Most of the world's hydrogen (about 97%) is currently derived from fossil fuels. For reduction of greenhouse gases, improvement of urban air quality, and energy security, among other reasons, carbon-free sources of hydrogen production are crucial to hydrogen becoming a significant energy carrier. Nuclear hydrogen production is a promising carbon-free alternative for large-scale, low-cost production of hydrogen in the future. Two nuclear technologies, applied in tandem, have a promising potential to generate hydrogen economically without leading to greenhouse gas emissions: 1) electrolysis and 2) thermochemical decomposition of water. This paper will investigate their unique complementary roles and economics of producing hydrogen, from a Canadian perspective. Together they can serve a unique potential for both de-centralized hydrogen needs in periods of low-demand electricity, and centralized base-load production from a nuclear station. Hydrogen production has a significantly higher thermal efficiency, but electrolysis can take advantage of low electricity prices during off-peak hours. By effectively linking these systems, water-based production of hydrogen can become more competitive against the predominant existing technology, SMR (steam-methane reforming). (orig.)

Low-cost process for hydrogen production

Science.gov (United States)

Cha, Chang Y.; Bauer, Hans F.; Grimes, Robert W.

1993-01-01

A method is provided for producing hydrogen and carbon black from hydrocarbon gases comprising mixing the hydrocarbon gases with a source of carbon and applying radiofrequency energy to the mixture. The hydrocarbon gases and the carbon can both be the products of gasification of coal, particularly the mild gasification of coal. A method is also provided for producing hydrogen an carbon monoxide by treating a mixture of hydrocarbon gases and steam with radio-frequency energy.

Hydrogen production from coal using a nuclear heat source

Science.gov (United States)

Quade, R. N.

1976-01-01

A strong candidate for hydrogen production in the intermediate time frame of 1985 to 1995 is a coal-based process using a high-temperature gas-cooled reactor (HTGR) as a heat source. Expected process efficiencies in the range of 60 to 70% are considerably higher than all other hydrogen production processes except steam reforming of a natural gas. The process involves the preparation of a coal liquid, hydrogasification of that liquid, and steam reforming of the resulting gaseous or light liquid product. A study showing process efficiency and cost of hydrogen vs nuclear reactor core outlet temperature has been completed, and shows diminishing returns at process temperatures above about 1500 F. A possible scenario combining the relatively abundant and low-cost Western coal deposits with the Gulf Coast hydrogen users is presented which provides high-energy density transportation utilizing coal liquids and uranium.

Out-of-pile demonstration test of hydrogen production system coupling with HTTR

International Nuclear Information System (INIS)

Inagaki, Yoshiyuki; Nishihara, Tetsuo; Takeda, Tetsuaki; Hada, Kazuhiko; Hayashi, Koji

1999-01-01

In Japan Atomic Energy Research Institute, a hydrogen production system is being designed to produce hydrogen by means of a steam reforming process of natural gas using nuclear heat (10 MW, 905degC) supplied by the High Temperature Engineering Test Reactor (HTTR). The safety principle and criteria are also being investigated in the HTTR hydrogen production system. Prior to coupling of the steam reforming system with the HTTR, an out-of-pile demonstration test was planned to confirm safety, controllability and performance of the steam reforming system under simulated operational conditions of the HTTR hydrogen production system. The out-of-pile test facility simulates key components downstream an intermediate heat exchanger of the HTTR hydrogen production system on a scale of 1 to 30 has a hydrogen production capacity of 110 Nm 3 /h using an electric heater as a reactor substitute. The test facility is under manufacturing aiming at completion in 2000 and followed by the test till 2004. In parallel to this, a hydrogen permeation test and a corrosion test of a catalyst tube of a steam reformer are being carried out to obtain data necessary for the design of the system. This report describes outline of the out-of-pile hydrogen production facility and demonstration test program for the HTTR hydrogen production system at present status. (author)

Out-of-pile demonstration test of hydrogen production system coupling with HTTR

Energy Technology Data Exchange (ETDEWEB)

Inagaki, Yoshiyuki; Nishihara, Tetsuo; Takeda, Tetsuaki; Hada, Kazuhiko; Hayashi, Koji [Japan Atomic Energy Research Inst., Oarai, Ibaraki (Japan). Oarai Research Establishment

1999-07-01

In Japan Atomic Energy Research Institute, a hydrogen production system is being designed to produce hydrogen by means of a steam reforming process of natural gas using nuclear heat (10 MW, 905degC) supplied by the High Temperature Engineering Test Reactor (HTTR). The safety principle and criteria are also being investigated in the HTTR hydrogen production system. Prior to coupling of the steam reforming system with the HTTR, an out-of-pile demonstration test was planned to confirm safety, controllability and performance of the steam reforming system under simulated operational conditions of the HTTR hydrogen production system. The out-of-pile test facility simulates key components downstream an intermediate heat exchanger of the HTTR hydrogen production system on a scale of 1 to 30 has a hydrogen production capacity of 110 Nm{sup 3}/h using an electric heater as a reactor substitute. The test facility is under manufacturing aiming at completion in 2000 and followed by the test till 2004. In parallel to this, a hydrogen permeation test and a corrosion test of a catalyst tube of a steam reformer are being carried out to obtain data necessary for the design of the system. This report describes outline of the out-of-pile hydrogen production facility and demonstration test program for the HTTR hydrogen production system at present status. (author)

Performance requirements of an inertial-fusion-energy source for hydrogen production

International Nuclear Information System (INIS)

Hovingh, J.

1983-01-01

Performance of an inertial fusion system for the production of hydrogen is compared to a tandem-mirror-system hydrogen producer. Both systems use the General Atomic sulfur-iodine hydrogen-production cycle and produce no net electric power to the grid. An ICF-driven hydrogen producer will have higher system gains and lower electrical-consumption ratios than the design point for the tandem-mirror system if the inertial-fusion-energy gain eta Q > 8.8. For the ICF system to have a higher hydrogen production rate per unit fusion power than the tandem-mirror system requires that eta Q > 17. These can be achieved utilizing realistic laser and pellet performances

Experimental evaluation of methane dry reforming process on a membrane reactor to hydrogen production

Energy Technology Data Exchange (ETDEWEB)

Silva, Fabiano S.A.; Benachour, Mohand; Abreu, Cesar A.M. [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. of Chemical Engineering], Email: f.aruda@yahoo.com.br

2010-07-01

In a fixed bed membrane reactor evaluations of methane-carbon dioxide reforming over a Ni/{gamma}- Al{sub 2}O{sub 3} catalyst were performed at 773 K, 823 K and 873 K. A to convert natural gas into syngas a fixed-bed reactor associate with a selective membrane was employed, where the operating procedures allowed to shift the chemical equilibrium of the reaction in the direction of the products of the process. Operations under hydrogen permeation, at 873 K, promoted the increase of methane conversion, circa 83%, and doubled the yield of hydrogen production, when compared with operations where no hydrogen permeation occurred. (author)

Manufacture of aromatic hydrocarbons from coal hydrogenation products

Energy Technology Data Exchange (ETDEWEB)

A.S. Maloletnev; M.A. Gyul' malieva [Institute for Fossil Fuels, Moscow (Russian Federation)

2007-08-15

The manufacture of aromatic hydrocarbons from coal distillates was experimentally studied. A flow chart for the production of benzene, ethylbenzene, toluene, and xylenes was designed, which comprised the hydrogen treatment of the total wide-cut (or preliminarily dephenolized) fraction with FBP 425{sup o}C; fractional distillation of the hydrotreated products into IBP-60, 60-180, 180-300, and 300-425{sup o}C fractions; the hydro-cracking of middle fractions for increasing the yield of gasoline fractions whenever necessary; the catalytic reform of the fractions with bp up to 180{sup o}C; and the extraction of aromatic hydrocarbons.

Thermochemical hydrogen production based on magnetic fusion

International Nuclear Information System (INIS)

Krikorian, O.H.; Brown, L.C.

1982-01-01

Conceptual design studies have been carried out on an integrated fusion/chemical plant system using a Tandem Mirror Reactor fusion energy source to drive the General Atomic Sulfur-Iodine Water-Splitting Cycle and produce hydrogen as a future feedstock for synthetic fuels. Blanket design studies for the Tandem Mirror Reactor show that several design alternatives are available for providing heat at sufficiently high temperatures to drive the General Atomic Cycle. The concept of a Joule-boosted decomposer is introduced in one of the systems investigated to provide heat electrically for the highest temperature step in the cycle (the SO 3 decomposition step), and thus lower blanket design requirements and costs. Flowsheeting and conceptual process designs have been developed for a complete fusion-driven hydrogen plant, and the information has been used to develop a plot plan for the plant and to estimate hydrogen production costs. Both public and private utility financing approaches have been used to obtain hydrogen production costs of $12-14/GJ based on July 1980 dollars

Renewable hydrogen production via thermochemical/electrochemical coupling

Energy Technology Data Exchange (ETDEWEB)

Ambrosini, Andrea [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Babiniec, Sean Michael [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Miller, James E. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2017-10-01

A coupled electrochemical/thermochemical cycle was investigated to produce hydrogen from renewable resources. Like a conventional thermochemical cycle, this cycle leverages chemical energy stored in a thermochemical working material that is reduced thermally by solar energy. However, in this concept, the stored chemical energy only needs to be partially, but not fully, capable of splitting steam to produce hydrogen. To complete the process, a proton-conducting membrane is driven to separate hydrogen as it is produced, thus shifting the thermodynamics toward further hydrogen production. This novel coupled-cycle concept provides several benefits. First, the required oxidation enthalpy of the reversible thermochemical material is reduced, enabling the process to occur at lower temperatures. Second, removing the requirement for spontaneous steam-splitting widens the scope of materials compositions, allowing for less expensive/more abundant elements to be used. Lastly, thermodynamics calculations suggest that this concept can potentially reach higher efficiencies than photovoltaic-to-electrolysis hydrogen production methods. This Exploratory Express LDRD involved assessing the practical feasibility of the proposed coupled cycle. A test stand was designed and constructed and proton-conducting membranes were synthesized. While the full proof of concept was not achieved, the individual components of the experiment were validated and new capabilities that can be leveraged by a variety of programs were developed.

Hydrogen production system coupled with high-temperature gas-cooled reactor (HTTR)

International Nuclear Information System (INIS)

Shiozawa, Shusaku

2003-01-01

On the HTTR program, R and D on nuclear reactor technology and R and D on thermal application technology such as hydrogen production and so on, are advanced. When carrying out power generation and thermal application such as hydrogen production and so on, it is, at first, necessary to supply nuclear heat safely, stably and in low cost, JAERI carries out some R and Ds on nuclear reactor technology using HTTR. In parallel to this, JAERI also carries out R and D for jointing nuclear reactor system with thermal application systems because of no experience in the world on high temperature heat of about 1,000 centigrade supplied by nuclear reactor except power generation, and R and D on thermochemical decomposition method IS process for producing hydrogen from water without exhaust of carbon dioxide. Here were described summaries on R and D on nuclear reactor technology, R and D on jointing technology using HTTR hydrogen production system, R and D on IS process hydrogen production, and comparison hydrogen production with other processes. (G.K.)

Electrocatalysis research for fuel cells and hydrogen production

CSIR Research Space (South Africa)

Mathe, MK

2012-01-01

Full Text Available The CSIR undertakes research in the Electrocatalysis of fuel cells and for hydrogen production. The Hydrogen South Africa (HySA) strategy supports research on electrocatalysts due to their importance to the national beneficiation strategy. The work...

USE OF THE MODULAR HELIUM REACTOR FOR HYDROGEN PRODUCTION

International Nuclear Information System (INIS)

SCHULTZ, K.R.

2003-01-01

OAK-B135 A significant ''Hydrogen Economy'' is predicted that will reduce our dependence on petroleum imports and reduce pollution and greenhouse gas emissions. Hydrogen is an environmentally attractive fuel that has the potential to displace fossil fuels, but contemporary hydrogen production is primarily based on fossil fuels. The author has recently completed a three-year project for the US Department of Energy (DOE) whose objective was to ''define an economically feasible concept for production of hydrogen, using an advanced high-temperature nuclear reactor as the energy source''. Thermochemical water-slitting, a chemical process that accomplishes the decomposition of water into hydrogen and oxygen, met this objective. The goal of the first phase of this study was to evaluate thermochemical processes which offer the potential for efficient, cost-effective, large-scale production of hydrogen, and to select one for further detailed consideration. They selected the Sulfur-Iodine cycle. In the second phase, they reviewed all the basic reactor types for suitability to provide the high temperature heat needed by the selected thermochemical water splitting cycle and chose the helium gas-cooled reactor. In the third phase they designed the chemical flowsheet for the thermochemical process and estimated the efficiency and cost of the process and the projected cost of producing hydrogen. These results are summarized in this report

An Overview of Natural Gas Conversion Technologies for Co-Production of Hydrogen and Value-Added Solid Carbon Products

Energy Technology Data Exchange (ETDEWEB)

Dagle, Robert A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Dagle, Vanessa [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Bearden, Mark D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Holladay, Jamelyn D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Krause, Theodore R. [Argonne National Lab. (ANL), Argonne, IL (United States); Ahmed, Shabbir [Argonne National Lab. (ANL), Argonne, IL (United States)

2017-11-16

This report was prepared in response to the U.S. Department of Energy Fuel Cell Technologies Office Congressional Appropriation language to support research on carbon-free production of hydrogen using new chemical processes that utilize natural gas to produce solid carbon and hydrogen. The U.S. produces 9-10 million tons of hydrogen annually with more than 95% of the hydrogen produced by steam-methane reforming (SMR) of natural gas. SMR is attractive because of its high hydrogen yield; but it also converts the carbon to carbon dioxide. Non-oxidative thermal decomposition of methane to carbon and hydrogen is an alternative to SMR and produces CO₂-free hydrogen. The produced carbon can be sold as a co-product, thus providing economic credit that reduces the delivered net cost of hydrogen. The combination of producing hydrogen with potentially valuable carbon byproducts has market value in that this allows greater flexibility to match the market prices of hydrogen and carbon. That is, the higher value product can subsidize the other in pricing decisions. In this report we highlight the relevant technologies reported in the literature—primarily thermochemical and plasma conversion processes—and recent research progress and commercial activities. Longstanding technical challenges include the high energetic requirements (e.g., high temperatures and/or electricity requirements) necessary for methane activation and, for some catalytic processes, the separation of solid carbon product from the spent catalyst. We assess current and new carbon product markets that could be served given technological advances, and we discuss technical barriers and potential areas of research to address these needs. We provide preliminary economic analysis for these processes and compare to other emerging (e.g., electrolysis) and conventional (e.g., SMR) processes for hydrogen production. The overarching conclusion of this study is that the cost of hydrogen can be potentially

PRODUCTION OF HYDROGEN FROM THE STEAM AND OXIDATIVE REFORMING OF LPG: THERMODYNAMIC AND EXPERIMENTAL STUDY

Directory of Open Access Journals (Sweden)

P. P. Silva

2015-09-01

Full Text Available AbstractThe objective of this paper was to use a thermodynamic analysis to find operational conditions that favor the production of hydrogen from steam and oxidative reforming of liquefied petroleum gas (LPG. We also analyzed the performance of a catalyst precursor, LaNiO3, in order to compare the performance of the obtained catalyst with the thermodynamic equilibrium predictions. The results showed that it is possible to produce high concentrations of hydrogen from LPG reforming. The gradual increase of temperature and the use of high water concentrations decrease the production of coke and increase the formation of H2. The reaction of oxidative reforming of LPG was more suitable for the production of hydrogen and lower coke formation. Furthermore the use of an excess of water (H2O/LPG =7.0 and intermediate temperatures (973 K are the most suitable conditions for the process.

In vitro hydrogen production by glucose dehydrogenase and hydrogenase

Energy Technology Data Exchange (ETDEWEB)

Woodward, J. [Oak Ridge National Lab., TN (United States)

1996-10-01

A new in vitro enzymatic pathway for the generation of molecular hydrogen from glucose has been demonstrated. The reaction is based upon the oxidation of glucose by Thermoplasma acidophilum glucose dehydrogenase with the concomitant oxidation of NADPH by Pyrococcus furiosus hydrogenase. Stoichiometric yields of hydrogen were produced from glucose with continuous cofactor recycle. This simple system may provide a method for the biological production of hydrogen from renewable sources. In addition, the other product of this reaction, gluconic acid, is a high-value commodity chemical.

Safe production and application of hydrogen at Munich airport

Energy Technology Data Exchange (ETDEWEB)

Szamer, R.

2005-07-01

At Munich International Airport the world's first public filling station for liquid and gaseous hydrogen with on-site hydrogen gas production has been installed. In order to prove the safety, liability and economic feasibility of hydrogen this pilot project examined the complete sequence of hydrogen production and application: on-site production with pressurized electrolyser and steam reformer, storage and filling of gaseous and liquid hydrogen, application of hydrogen for propelling several vehicles, e.g. airport busses in day to day operation, cars, fork lifter. TUV SUD Group, one of the largest service provider for technical safety and quality, was involved in the safety evaluation of the hydrogen project from the very beginning with the following services: safety consultancy throughout all project phases, e.g. for licensing procedures, plant design and operation safety analysis of the overall plant and of subsystems (electrolyser, filling stations, storage tanks, control systems etc.) safety assessment and acceptance testing of CH2 busses, CH2 fork lifter and LH2 passenger cars inspections and tests The challenges of this complex project relating to safety will be presented in the lecture, e.g. identification of potential hazards, safety requirements for the design and operation of the hydrogen plant as wells as for the various applications. Project description The hydrogen plant (cf. Figure 1) comprises two supply paths, one for compressed gaseous hydrogen (CH2) and one for cryogenic liquid hydrogen. Gaseous hydrogen is produced via high-pressure electrolysis at an operating pressure of 3 MPa (30 bar) and/or steam reforming process. The hydrogen will be led into a compressor, compressed to 35 MPa (350 bar) and stored in high pressure cylinders with a total geometrical storage volume of 10 m. The cylinders supply the high-pressure filling stations which refuels the 3 hydrogen buses and the fork lifter. Liquid hydrogen (LH2) is delivered in tank trucks and

Hydrogen Production by Geobacter Species and a Mixed Consortium in a Microbial Electrolysis Cell

KAUST Repository

Call, D. F.

2009-10-09

A hydrogen utilizing exoelectrogenic bacterium (Geobacter sulfurreducens) was compared to both a nonhydrogen oxidizer (Geobacter metallireducens) and a mixed consortium in order to compare the hydrogen production rates and hydrogen recoveries of pure and mixed cultures in microbial electrolysis cells (MECs). At an applied voltage of 0.7 V, both G. sulfurreducens and the mixed culture generated similar current densities (ca. 160 A/m3), resulting in hydrogen production rates of ca. 1.9 m3 H2/m 3/day, whereas G. metallireducens exhibited lower current densities and production rates of 110 ± 7 A/m3 and 1.3 ± 0.1 m3 H2/m3/day, respectively. Before methane was detected in the mixed-culture MEC, the mixed consortium achieved the highest overall energy recovery (relative to both electricity and substrate energy inputs) of 82% ± 8% compared to G. sulfurreducens (77% ± 2%) and G. metallireducens (78% ± 5%), due to the higher coulombic efficiency of the mixed consortium. At an applied voltage of 0.4 V, methane production increased in the mixed-culture MEC and, as a result, the hydrogen recovery decreased and the overall energy recovery dropped to 38% ± 16% compared to 80% ± 5% for G. sulfurreducens and 76% ± 0% for G. metallireducens. Internal hydrogen recycling was confirmed since the mixed culture generated a stable current density of 31 ± 0 A/m3 when fed hydrogen gas, whereas G. sulfurreducens exhibited a steady decrease in current production. Community analysis suggested that G. sulfurreducens was predominant in the mixed-culture MEC (72% of clones) despite its relative absence in the mixed-culture inoculum obtained from a microbial fuel cell reactor (2% of clones). These results demonstrate that Geobacter species are capable of obtaining similar hydrogen production rates and energy recoveries as mixed cultures in an MEC and that high coulombic efficiencies in mixed culture MECs can be attributed in part to the recycling of hydrogen into current. Copyright �

Hydrogen Production by Geobacter Species and a Mixed Consortium in a Microbial Electrolysis Cell▿

Science.gov (United States)

Call, Douglas F.; Wagner, Rachel C.; Logan, Bruce E.

2009-01-01

A hydrogen utilizing exoelectrogenic bacterium (Geobacter sulfurreducens) was compared to both a nonhydrogen oxidizer (Geobacter metallireducens) and a mixed consortium in order to compare the hydrogen production rates and hydrogen recoveries of pure and mixed cultures in microbial electrolysis cells (MECs). At an applied voltage of 0.7 V, both G. sulfurreducens and the mixed culture generated similar current densities (ca. 160 A/m3), resulting in hydrogen production rates of ca. 1.9 m3 H2/m3/day, whereas G. metallireducens exhibited lower current densities and production rates of 110 ± 7 A/m3 and 1.3 ± 0.1 m3 H2/m3/day, respectively. Before methane was detected in the mixed-culture MEC, the mixed consortium achieved the highest overall energy recovery (relative to both electricity and substrate energy inputs) of 82% ± 8% compared to G. sulfurreducens (77% ± 2%) and G. metallireducens (78% ± 5%), due to the higher coulombic efficiency of the mixed consortium. At an applied voltage of 0.4 V, methane production increased in the mixed-culture MEC and, as a result, the hydrogen recovery decreased and the overall energy recovery dropped to 38% ± 16% compared to 80% ± 5% for G. sulfurreducens and 76% ± 0% for G. metallireducens. Internal hydrogen recycling was confirmed since the mixed culture generated a stable current density of 31 ± 0 A/m3 when fed hydrogen gas, whereas G. sulfurreducens exhibited a steady decrease in current production. Community analysis suggested that G. sulfurreducens was predominant in the mixed-culture MEC (72% of clones) despite its relative absence in the mixed-culture inoculum obtained from a microbial fuel cell reactor (2% of clones). These results demonstrate that Geobacter species are capable of obtaining similar hydrogen production rates and energy recoveries as mixed cultures in an MEC and that high coulombic efficiencies in mixed culture MECs can be attributed in part to the recycling of hydrogen into current. PMID:19820150

Optical pumping production of spin polarized hydrogen

International Nuclear Information System (INIS)

Knize, R.J.; Happer, W.; Cecchi, J.L.

1984-01-01

There has been much interest recently in the production of large quantities of spin polarized hydrogen in various fields including controlled fusion, quantum fluids, high energy, and nuclear physics. One promising method for the development of large quantities of spin polarized hydrogen is the utilization of optical pumping with a laser. Optical pumping is a process where photon angular momentum is converted into electron and nuclear spin. The advent of tunable CW dye lasers (approx. 1 watt) allow the production of greater than 10 18 polarized atoms/sec. We have begun a program at Princeton to investigate the physics and technology of using optical pumping to produce large quantities of spin polarized hydrogen. Initial experiments have been done in small closed glass cells. Eventually, a flowing system, open target, or polarized ion source could be constructed

Evaluation of hydrogen production system coupling with HTTR using dynamic analysis code

International Nuclear Information System (INIS)

Sato, Hiroyuki; Ohashi, Hirofumi; Inaba, Yoshitomo; Nishihara, Tetsuo; Hayashi, Koji; Inagaki, Yoshiyuki

2006-01-01

The Japan Atomic Energy Agency (JAEA) was entrusted 'Development of Nuclear Heat Utilization Technology' by Ministry of Education, Culture, Sports, Science and Technology. In this development, the JAEA investigated the system integration technology to couple the hydrogen production system by steam reforming with the High Temperature Engineering Test Reactor (HTTR). Prior to the construction of the hydrogen production system coupling with the HTTR, a dynamic analysis code had to be developed to evaluate the system transient behaviour of the hydrogen production system because there are no examples of chemical facilities coupled with nuclear reactor in the world. This report describes the evaluation of the hydrogen production system coupling with HTTR using analysis code, N-HYPAC, which can estimate transient behaviour of the hydrogen production system by steam reforming. The results of this investigation provide that the influence of the thermal disturbance caused by the hydrogen production system on the HTTR can be estimated well. (author)

Development and Characterization of Titanium Dioxide Gel with Encapsulated Bacteriorhodopsin for Hydrogen Production.

Science.gov (United States)

Johnson, Kaitlin E; Gakhar, Sukriti; Risbud, Subhash H; Longo, Marjorie L

2018-06-06

We study bacteriorhodopsin (BR) in its native purple membrane encapsulated within amorphous titanium dioxide, or titania, gels and in the presence of titania sol-particles to explore this system for hydrogen production. Förster resonance energy transfer between BR and titanium dioxide sol particles was used to conclude that there is nanometer-scale proximity of bacteriorhodopsin to the titanium dioxide. The detection of BR-titania sol aggregates by fluorescence anisotropy and particle sizing indicated the affinity amorphous titania has for BR without the use of additional cross-linkers. UV-Visible spectroscopy of BR-titania gels show that methanol addition did not denature BR at a 25 mM concentration presence as a sacrificial electron donor. Additionally, confinement of BR in the gels significantly limited protein denaturation at higher concentration of added methanol or ethanol. Subsequently, titania gels fabricated through the sol-gel process using a titanium ethoxide precursor, water and the addition of 25 mM methanol were used to encapsulate BR and a platinum reduction catalyst for the production of hydrogen gas under white light irradiation. The inclusion of 5 µM bacteriorhodopsin resulted in a hydrogen production rate of about 3.8 µmole hydrogen mL -1 hr -1 , an increase of 52% compared to gels containing no protein. Electron transfer and proton pumping by BR in close proximity to the titania gel surface are feasible explanations for the enhanced production of hydrogen without the need to crosslink BR to the titania gel. This work sets the stage for further developments of amorphous, rather than crystalline, titania-encapsulated bacteriorhodopsin for solar-driven hydrogen production through water-splitting.

Integrated analysis of transportation demand pathway options for hydrogen production, storage, and distribution

Energy Technology Data Exchange (ETDEWEB)

Thomas, C.E.S. [Directed Technologies Inc., Arlington, VA (United States)

1996-10-01

Directed Technologies, Inc. has begun the development of a computer model with the goal of providing guidance to the Hydrogen Program Office regarding the most cost effective use of limited resources to meet national energy security and environmental goals through the use of hydrogen as a major energy carrier. The underlying assumption of this programmatic pathway model is that government and industry must work together to bring clean hydrogen energy devices into the marketplace. Industry cannot provide the long term resources necessary to overcome technological, regulatory, institutional, and perceptual barriers to the use of hydrogen as an energy carrier, and government cannot provide the substantial investments required to develop hydrogen energy products and increased hydrogen production capacity. The computer model recognizes this necessary government/industry partnership by determining the early investments required by government to bring hydrogen energy end uses within the time horizon and profitability criteria of industry, and by estimating the subsequent investments required by industry. The model then predicts the cost/benefit ratio for government, based on contributions of each hydrogen project to meeting societal goals, and it predicts the return on investment for industry. Sensitivity analyses with respect to various government investments such as hydrogen research and development and demonstration projects will then provide guidance as to the most cost effective mix of government actions. The initial model considers the hydrogen transportation market, but this programmatic pathway methodology will be extended to other market segments in the future.

Fixed-bed hydrogen pyrolysis of rapeseed: product yields and compositions

International Nuclear Information System (INIS)

Onay, O.; Kockar, O.M.; Gaines, A.F.; Snape, C.E.

2006-01-01

The fixed-bed hydro pyrolysis tests have been conducted on a sample of rapeseed to investigate the effect of hydro pyrolysis on the yields and chemical structures of bio-oils, with a view to improving overall product quality. A ammonium dioxydithiomolybdenate catalyst has been used in some tests to further increase conversion. The maximum bio-oil yield of 84% was obtained in hydrogen atmosphere (with catalyst) at hydrogen pressure of 15 MPa, hydrogen flow rate of 10 dm 3 min -1 , hydro pyrolysis temperature of 520 degree C, and heating rate of 5 o Cmin -1 . Then this bio-oil was characterized by elemental analysis and some spectroscopic and chromatographic techniques. And finally, this bio-oil yield and chemical composition compared with oil obtained from fast pyrolysis condition

Hydrogen production from palm oil mill effluent by fermentation

Energy Technology Data Exchange (ETDEWEB)

Tanisho, S.; Shimazaki, T. [Yokohama National Univ., Shigeharu TANISHO and Tsuruyo SHIMAZAKI, Yokohama (Japan)

2003-09-01

Hydrogen production by fermentation was examined by using palm oil mill effluent. Clostridium butyricum produced more than 2.2 NL of hydrogen from 1 L of raw POME at pH 5.0, and Enterobacter aerogenes produced ca. 1.9 NL at pH 6.0. While from the culture liquid added 1% of peptone on the raw POME, C. butyricum produced more than 3.3 NL and also E. aerogenes 3.4 NL at pH 6.0 and 5.0, respectively. In this manner, the addition of nitrogen source to the POME liquid exerted an influence on the volume of hydrogen production. Since Aspergillus niger has ability to produce cellulase, co-cultivation of C.butyricum with A. niger was tried to utilize celluloses in the POME. Against our expectations, however, the results were lower productivities than pure cultivation's. We analyzed the components of POME by liquid chromatography and capillary electrophoresis before and after cultivation. The main substrate for hydrogen production was found to be glycerol. (authors)

Performance test results of mock-up test facility of HTTR hydrogen production system

International Nuclear Information System (INIS)

Ohashi, Hirofumi; Inaba, Yoshitomo; Nishihara, Tetsuo

2004-01-01

For the purpose to demonstrate effectiveness of high-temperature nuclear heat utilization, Japan Atomic Energy Research Institute has been developing a hydrogen production system and has planned to connect the hydrogen production system to High Temperature Engineering Test Reactor (HTTR). Prior to construction of a HTTR hydrogen production system, a mock-up test facility was constructed to investigate transient behavior of the hydrogen production system and to establish system controllability. The Mock-up test facility with a full-scale reaction tube is an approximately 1/30-scale model of the HTTR hydrogen production system and an electric heater is used as a heat source instead of a reactor. After its construction, a performance test of the test facility was carried out in the same pressure and temperature conditions as those of the HTTR hydrogen production system to investigate its performance such as hydrogen production ability, controllability and so on. It was confirmed that hydrogen was stably produced with a hot helium gas about 120m 3 /h, which satisfy the design value, and thermal disturbance of helium gas during the start-up could be mitigated within the design value by using a steam generator. The mock-up test of the HTTR hydrogen production system using this facility will continue until 2004. (author)

Liquid hydrogen production and economics for NASA Kennedy Space Center

Science.gov (United States)

Block, D. L.

1985-12-01

Detailed economic analyses for the production of liquid hydrogen used to power the Space Shuttle are presented. The hydrogen production and energy needs of the NASA Kennedy Space Center are reviewed, and steam reformation, polygeneration, and electrolysis for liquid hydrogen production are examined on an equal economic basis. The use of photovoltaics as an electrolysis power source is considered. The 1985 present worth is calculated based on life cycle costs over a 21-year period beginning with full operation in 1990. Two different sets of escalation, inflation, and discount rates are used, with revenue credit being given for energy or other products of the hydrogen production process. The results show that the economic analyses are very dependent on the escalation rates used. The least net present value is found for steam reformation of natural gas, while the best net present value is found for the electrolysis process which includes the phasing of photovoltaics.

An Integrated Hydrogen Production-CO2 Capture Process from Fossil Fuel

Energy Technology Data Exchange (ETDEWEB)

Zhicheng Wang

2007-03-15

The new technology concept integrates two significant complementary hydrogen production and CO{sub 2}-sequestration approaches that have been developed at Oak Ridge National Laboratory (ORNL) and Clark Atlanta University. The process can convert biomass into hydrogen and char. Hydrogen can be efficiently used for stationary power and mobile applications, or it can be synthesized into Ammonia which can be used for CO{sub 2}-sequestration, while char can be used for making time-release fertilizers (NH{sub 4}HCO{sub 3}) by absorption of CO{sub 2} and other acid gases from exhaust flows. Fertilizers are then used for the growth of biomass back to fields. This project includes bench scale experiments and pilot scale tests. The Combustion and Emission Lab at Clark Atlanta University has conducted the bench scale experiments. The facility used for pilot scale tests was built in Athens, GA. The overall yield from this process is 7 wt% hydrogen and 32 wt% charcoal/activated carbon of feedstock (peanut shell). The value of co-product activated carbon is about $1.1/GJ and this coproduct reduced the selling price of hydrogen. And the selling price of hydrogen is estimated to be $6.95/GJ. The green house experimental results show that the samples added carbon-fertilizers have effectively growth increase of three different types of plants and improvement ability of keeping fertilizer in soil to avoid the fertilizer leaching with water.

Contribution to the study of new hydrogen production, purification and storage processes

International Nuclear Information System (INIS)

Manaud, Jean-Pierre

1984-01-01

This research thesis addresses the various aspects of hydrogen production, purification and process within the scope of hydrogen-based energy production. Hydrogen production is achieved by water decomposition through a thermo-chemical process. The author reports the thermodynamic assessment of a water decomposition thermo-chemical cycle for chlorine and sulphur-related cycles. He reports the experimental investigation of hydrogen purification by selective diffusion, the study of contamination of a CeMg12 alloy by nitrogen, oxygen and water vapour with application to hydrogen storage under the form of hydrides [fr

Startech Hydrogen Production Final Technical Report

Energy Technology Data Exchange (ETDEWEB)

Startech Engineering Department

2007-11-27

The assigned work scope includes the modification and utilization of the Plasma Converter System, Integration of a StarCell{trademark} Multistage Ceramic Membrane System (StarCell), and testing of the integrated systems towards DOE targets for gasification and membrane separation. Testing and evaluation was performed at the Startech Engineering and Demonstration Test Center in Bristol, CT. The Objectives of the program are as follows: (1) Characterize the performance of the integrated Plasma Converter and StarCell{trademark} Systems for hydrogen production and purification from abundant and inexpensive feedstocks; (2) Compare integrated hydrogen production performance to conventional technologies and DOE benchmarks; (3) Run pressure and temperature testing to baseline StarCell's performance; and (4) Determine the effect of process contaminants on the StarCell{trademark} system.

Process for the production of hydrogen from water

Science.gov (United States)

Miller, William E [Naperville, IL; Maroni, Victor A [Naperville, IL; Willit, James L [Batavia, IL

2010-05-25

A method and device for the production of hydrogen from water and electricity using an active metal alloy. The active metal alloy reacts with water producing hydrogen and a metal hydroxide. The metal hydroxide is consumed, restoring the active metal alloy, by applying a voltage between the active metal alloy and the metal hydroxide. As the process is sustainable, only water and electricity is required to sustain the reaction generating hydrogen.

The hydrogen resource. Productive, technical and economic analysis

International Nuclear Information System (INIS)

De Fronzo, G.

2000-01-01

Diffusion of hydrogen as an energetic vector meets with a lot of obstacles that don't depend on available raw material, but on hydrogen combination with other elements. It is necessary, therefore, to separate hydrogen picking out the available different technologies to have different pure hydrogen of variable quantities. Besides, its diffusion as fuel is limited because of the great production cost compared to fuels sprung from petroleum. Hydrogen used on a large scale could have advantages on the environment and occupation, but there are economic and politic obstacles to limit its diffusion. Future of economic system, based on hydrogen as the main energetic vector, will depend on the programme that national and international qualified governing bodies will be able to do [it

Renewable hydrogen utilisation for the production of methanol

International Nuclear Information System (INIS)

Galindo Cifre, P.; Badr, O.

2007-01-01

Electrolytic hydrogen production is an efficient way of storing renewable energy generated electricity and securing the contribution of renewables in the future electricity supply. The use of this hydrogen for the production of methanol results in a liquid fuel that can be utilised directly with minor changes in the existing infrastructure. To utilise the renewable generated hydrogen for production of renewable methanol, a sustainable carbon source is needed. This carbon can be provided by biomass or CO 2 in the flue gases of fossil fuel-fired power stations, cement factories, fermentation processes and water purification plants. Methanol production pathways via biomass gasification and CO 2 recovery from the flue gasses of a fossil fuel-fired power station have been reviewed in this study. The cost of methanol production from biomass was found to lie in the range of 300-400 EUR/tonne of methanol, and the production cost of CO 2 based methanol was between 500 and 600 EUR/tonne. Despite the higher production costs compared with methanol produced by conventional natural gas reforming (i.e. 100-200 EUR/tonne, aided by the low current price of natural gas), these new processes incorporate environmentally beneficial aspects that have to be taken into account. (author)

Renewable energy for hydrogen production and sustainable urban mobility

International Nuclear Information System (INIS)

Briguglio, N.; Andaloro, L.; Ferraro, M.; Di Blasi, A.; Dispenza, G.; Antonucci, V.; Matteucci, F.; Breedveld, L.

2010-01-01

In recent years, the number of power plants based on renewable energy (RWE) has been increasing and hydrogen as an energy carrier has become a suitable medium-to-long term storage solution as well as a ''fuel'' for FCEV's because of its CO 2 -free potential. In this context, the aim of the present study is to carry out both an economic and environmental analysis of a start-up RWE plant using a simulation code developed in previous work and a Life Cycle Assessment (LCA). The plant will be located in the South of Italy (Puglia) and will consist of different RWE sources (Wind Power, Photovoltaic, Biomass). RWE will be used to produce hydrogen from an electrolyzer, which will feed a fleet of buses using different fuels (methane, hydrogen, or a mixture of these). In particular, a wind turbine of 850 kW will feed a hydrogen production plant and a biomass plant will produce methane. Preliminary studies have shown that it is possible to obtain hydrogen at a competitive cost (DOE target) and that components (wind turbine, electrolyzer, vessel, etc.) influence the final price. In addition, LCA results have permitted a comparison of different minibuses using either fossil fuels or renewable energy sources. (author)

Renewable energy for hydrogen production and sustainable urban mobility

Energy Technology Data Exchange (ETDEWEB)

Briguglio, N.; Andaloro, L.; Ferraro, M.; Di Blasi, A.; Dispenza, G.; Antonucci, V. [Istituto di Tecnologie avanzate per l' Energia ' ' Nicola Giordano' ' Salita S, Lucia sopra Contesse, 5, 98126 Messina (Italy); Matteucci, F. [TRE SpA Tozzi Renewable Energy, Via Zuccherificio, 10, 48100 Mezzano (RA) (Italy); Breedveld, L. [2B Via della Chiesa Campocroce, 4, 31021 Mogliano Veneto (TV) (Italy)

2010-09-15

In recent years, the number of power plants based on renewable energy (RWE) has been increasing and hydrogen as an energy carrier has become a suitable medium-to-long term storage solution as well as a ''fuel'' for FCEV's because of its CO{sub 2}-free potential. In this context, the aim of the present study is to carry out both an economic and environmental analysis of a start-up RWE plant using a simulation code developed in previous work and a Life Cycle Assessment (LCA). The plant will be located in the South of Italy (Puglia) and will consist of different RWE sources (Wind Power, Photovoltaic, Biomass). RWE will be used to produce hydrogen from an electrolyzer, which will feed a fleet of buses using different fuels (methane, hydrogen, or a mixture of these). In particular, a wind turbine of 850 kW will feed a hydrogen production plant and a biomass plant will produce methane. Preliminary studies have shown that it is possible to obtain hydrogen at a competitive cost (DOE target) and that components (wind turbine, electrolyzer, vessel, etc.) influence the final price. In addition, LCA results have permitted a comparison of different minibuses using either fossil fuels or renewable energy sources. (author)

Thermodynamic comparison of two processes of hydrogen production: steam methane reforming-A solar thermochemical process

International Nuclear Information System (INIS)

Gomri, Rabah; Boumaza, Mourad

2006-01-01

Hydrogen is mainly employed like primary product, for the synthesis of ammonia. The ammonia is synthesized by chemically combining hydrogen and nitrogen under pressure, in the presence of a catalyst. This ammonia is used, for the production of the nitrate fertilizers. Nowadays hydrogen gains more attention mainly because, it is regarded as a future significant fuel by much of experts. The widespread use of hydrogen as source of energy could help to reduce the concern concerning the safety of energy, the total change of climate and the quality of air. Hydrogen is presented then as an excellent alternate initially and as substitute thereafter. It can play a role even more significant than conventional energies. Indeed, it has the advantage of being nonpolluting and it can use the same means of transport as conventional energies. For Algeria, it proves of importance capital. It not only makes it possible to increase and diversify its energy reserves and its exports but also to provide for its energy needs which become increasingly significant. Although hydrogen can be produced starting from a large variety of resources using a range of various technologies, the natural gas is generally preferred and will remain in the near future the principal primary product for the manufacture of hydrogen. Currently the most effective means of production of hydrogen is the Steam Reforming of Natural Gas (SMR). This process is seen as a one of principal technologies for the production of hydrogen. The disadvantages of this process it's that it consumes a great quantity of primary energy and that it releases in the atmosphere the gases that contribute to the warming of the plane. Among the alternatives processes of hydrogen production one can quote solar thermochemical processes. In this study, an exergetic analysis of the process of hydrogen production based on Zn/ZnO redox reactions is presented. In the first part of this study, an exergetic analysis is made for a temperature of the

Study of metabolic pathways for hydrogen production in chlamydomonas reinhardtii and transposition on a torus photo bioreactor; Etude des voies metaboliques de production d'hydrogene chez la microalgue Chlamydomonas reinhardtii et transposition en photobioreacteur

Energy Technology Data Exchange (ETDEWEB)

Fouchard, S

2006-04-15

Considering the recent increase in energy consumption. aide associated environmental risks, new trails are followed today to develop the use of clean and renewable alternative energies. In this context hydrogen seems to be a serious solution and this study, based on micro-algae photosynthetic capacities exploitation, will allow to devise a process for hydrogen production from only water and solar energy without greenhouse gas release. The sulphur deprivation protocol on TAP medium, known to lead to hydrogen production in Chlamydomonas reinhardtii species was particularly studied. At the metabolic level, two important phenomena are induced under these conditions: an over-accumulation of the intracellular starch reserves and a simultaneous alteration of the PsII activity which leads to anoxia and Fe-hydrogenase induction, an enzyme with a strong specific activity responsible for the hydrogen production. The contribution of the two electron transfer pathways implied in the hydrogen production process (PsII-dependent and PSII-independent) as well as the importance of the previously accumulated starch were highlighted here. We also investigated the potential for designing autotrophic protocols for hydrogen photoproduction. Various protocols, considered to be relevant, were then transposed on a torus photo-bioreactor, specifically developed in this study and which allows the control of culture parameters as well as the precise measurement of gas release kinetics, in order to obtain first estimates of productivity of the system. Integration of the physical; aspects of the pilot and biological aspects of the process in a model, finally opens new prospects for subject development, in particular for a reasoned optimization of hydrogen production via this double physiology/process approach. (author)

Analysis of economic and infrastructure issues associated with hydrogen production from nuclear energy

International Nuclear Information System (INIS)

Summers, W.A.; Gorensek, M.B.; Danko, E.; Schultz, K.R.; Richards, M.B.; Brown, L.C.

2004-01-01

Consideration is being given to the large-scale transition of the world's energy system from one based on carbon fuels to one based on the use of hydrogen as the carrier. This transition is necessitated by the declining resource base of conventional oil and gas, air quality concerns, and the threat of global climate change linked to greenhouse gas emissions. Since hydrogen can be produced from water using non-carbon primary energy sources, it is the ideal sustainable fuel. The options for producing the hydrogen include renewables (e.g. solar and wind), fossil fuels with carbon sequestration, and nuclear energy. A comprehensive study has been initiated to define economically feasible concepts and to determine estimates of efficiency and cost for hydrogen production using next generation nuclear reactors. A unique aspect of the study is the assessment of the integration of a nuclear plant, a hydrogen production process and the broader infrastructure requirements. Hydrogen infrastructure issues directly related to nuclear hydrogen production are being addressed, and the projected cost, value and end-use market for hydrogen will be determined. The infrastructure issues are critical, since the combined cost of storing, transporting, distributing, and retailing the hydrogen product could well exceed the cost of hydrogen production measured at the plant gate. The results are expected to be useful in establishing the potential role that nuclear hydrogen can play in the future hydrogen economy. Approximately half of the three-year study has been completed. Results to date indicate that nuclear produced hydrogen can be competitive with hydrogen produced from natural gas for use at oil refineries or ammonia plants, indicating a potential early market opportunity for large-scale centralized hydrogen production. Extension of the hydrogen infrastructure from these large industrial users to distributed hydrogen users such as refueling stations and fuel cell generators could

Timeline of bio-hydrogen production by anaerobic digestion of biomass

Directory of Open Access Journals (Sweden)

Bernadette E. TELEKY

2015-12-01

Full Text Available Anaerobic digestion of biomass is a process capable to produce biohydrogen, a clean source of alternative energy. Lignocellulosic biomass from agricultural waste is considered a renewable energy source; therefore its utilization also contributes to the reduction of water, soil and air pollution. The study consists in five consecutive experiments designed to utilize anaerobic bacterial enrichment cultures originating from the Hungarian Lake, Hévíz. Wheat straw was used as complex substrate to produce hydrogen. The timeline evolution of hydrogen production was analyzed and modelled by two functions: Logistic and Boltzmann. The results proved that hydrogen production is significant, with a maximum of 0.24 mlN/ml and the highest hydrogen production occurs between the days 4-10 of the experiment.

Degradation of 2,4,6-Trichlorophenol and hydrogen production simultaneously by TiO2 nanotubes/graphene composite

Science.gov (United States)

Slamet, Raudina

2017-11-01

Industrial waters in coal pyrolysis process, synthetic chemicals and oil and gas process contain phenol derivatives that are dangerous to the environment and needs to be removed, one of them is 2,4,6-Trichlorophenol. Degradation of 2,4,6-Trichlorophenol and hydrogen production simultaneously have been investigated using TiNT/Graphene composite at various graphene loading and initial concentration of 2,4,6-Trichlorophenol. Optimal graphene loading of 0.6 wt% was obtained in the simultaneous system with 89% elimination of 2,4,6-Trichlorophenol and 986 µmol of hydrogen production. Test results showed that addition of 2,4,6-Trichlorophenol would subsequently increased 2,4,6-Trichlorophenol conversion and enhanced hydrogen production linearly. 2.7 times greater hydrogen production was found in addition of 50 ppm 2,4,6-Trichlorophenol.

Hydrogen sulfide production from cysteine and homocysteine by periodontal and oral bacteria.

Science.gov (United States)

Yoshida, Akihiro; Yoshimura, Mamiko; Ohara, Naoya; Yoshimura, Shigeru; Nagashima, Shiori; Takehara, Tadamichi; Nakayama, Koji

2009-11-01

Hydrogen sulfide is one of the predominant volatile sulfur compounds (VSCs) produced by oral bacteria. This study developed and evaluated a system for detecting hydrogen sulfide production by oral bacteria. L-methionine-alpha-deamino-gamma-mercaptomethane-lyase (METase) and beta carbon-sulfur (beta C-S) lyase were used to degrade homocysteine and cysteine, respectively, to produce hydrogen sulfide. Enzymatic reactions resulting in hydrogen sulfide production were assayed by reaction with bismuth trichloride, which forms a black precipitate when mixed with hydrogen sulfide. The enzymatic activities of various oral bacteria that result in hydrogen sulfide production and the capacity of bacteria from periodontal sites to form hydrogen sulfide in reaction mixtures containing L-cysteine or DL-homocysteine were assayed. With L-cysteine as the substrate, Streptococcus anginosus FW73 produced the most hydrogen sulfide, whereas Porphyromonas gingivalis American Type Culture Collection (ATCC) 33277 and W83 and Fusobacterium nucleatum ATCC 10953 produced approximately 35% of the amount produced by the P. gingivalis strains. Finally, the hydrogen sulfide found in subgingival plaque was analyzed. Using bismuth trichloride, the hydrogen sulfide produced by oral bacteria was visually detectable as a black precipitate. Hydrogen sulfide production by oral bacteria was easily analyzed using bismuth trichloride. However, further innovation is required for practical use.

Engineering Synechocystis PCC6803 for hydrogen production: influence on the tolerance to oxidative and sugar stresses.

Directory of Open Access Journals (Sweden)

Marcia Ortega-Ramos

Full Text Available In the prospect of engineering cyanobacteria for the biological photoproduction of hydrogen, we have studied the hydrogen production machine in the model unicellular strain Synechocystis PCC6803 through gene deletion, and overexpression (constitutive or controlled by the growth temperature. We demonstrate that the hydrogenase-encoding hoxEFUYH operon is dispensable to standard photoautotrophic growth in absence of stress, and it operates in cell defense against oxidative (H₂O₂ and sugar (glucose and glycerol stresses. Furthermore, we showed that the simultaneous over-production of the proteins HoxEFUYH and HypABCDE (assembly of hydrogenase, combined to an increase in nickel availability, led to an approximately 20-fold increase in the level of active hydrogenase. These novel results and mutants have major implications for those interested in hydrogenase, hydrogen production and redox metabolism, and their connections with environmental conditions.

Photobiological hydrogen production and carbon dioxide sequestration

Science.gov (United States)

Berberoglu, Halil

Photobiological hydrogen production is an alternative to thermochemical and electrolytic technologies with the advantage of carbon dioxide sequestration. However, it suffers from low solar to hydrogen energy conversion efficiency due to limited light transfer, mass transfer, and nutrient medium composition. The present study aims at addressing these limitations and can be divided in three parts: (1) experimental measurements of the radiation characteristics of hydrogen producing and carbon dioxide consuming microorganisms, (2) solar radiation transfer modeling and simulation in photobioreactors, and (3) parametric experiments of photobiological hydrogen production and carbon dioxide sequestration. First, solar radiation transfer in photobioreactors containing microorganisms and bubbles was modeled using the radiative transport equation (RTE) and solved using the modified method of characteristics. The study concluded that Beer-Lambert's law gives inaccurate results and anisotropic scattering must be accounted for to predict the local irradiance inside a photobioreactor. The need for accurate measurement of the complete set of radiation characteristics of microorganisms was established. Then, experimental setup and analysis methods for measuring the complete set of radiation characteristics of microorganisms have been developed and successfully validated experimentally. A database of the radiation characteristics of representative microorganisms have been created including the cyanobacteria Anabaena variabilis, the purple non-sulfur bacteria Rhodobacter sphaeroides and the green algae Chlamydomonas reinhardtii along with its three genetically engineered strains. This enabled, for the first time, quantitative assessment of the effect of genetic engineering on the radiation characteristics of microorganisms. In addition, a parametric experimental study has been performed to model the growth, CO2 consumption, and H 2 production of Anabaena variabilis as functions of

Renewable energy from biomass: a sustainable option? - Hydrogen production from alcohols

Science.gov (United States)

Balla, Zoltán; Kith, Károly; Tamás, András; Nagy, Orsolya

2015-04-01

in the case, than the same volume of ethanol-water mixture can be prepared. The renewal of alcohol, the alcohol-water mixture is then passed through the catalytic reformer into a preheater. The exhaust gas contains a relatively large number of carbon monoxide, which would spoil the fuel cell, so the carbon monoxide concentration to a high and a low temperature water-gas reaction is reduced. This increases the hydrogen production. The last step of the carbon monoxide content to eliminate preferential oxidation. The alcohol reforming catalyst for the precious metals spread most of what arose from high activity and stability. However, the precious metals are very expensive, so a non-precious metal catalysts is the design and development of objective activity and stability which reaches the precious metal catalysts of. Using the new reaction catalysts opportunities are created, which are smaller than the activation energy than the non-catalytic process. The basic objective of the technological developments more active at lower temperatures, the selective target product, long-life, low cost design catalysts.

Formate detection by potassium permanganate for enhanced hydrogen production in Escherichia coli

Energy Technology Data Exchange (ETDEWEB)

Maeda, Toshinari [Artie McFerrin Department of Chemical Engineering, 220 Jack E. Brown Building, Texas A and M University, College Station, TX 77843-3122 (United States); Wood, Thomas K. [Artie McFerrin Department of Chemical Engineering, 220 Jack E. Brown Building, Texas A and M University, College Station, TX 77843-3122 (United States); Department of Biology, Texas A and M University, College Station, TX 77843-3258 (United States); Zachry Department of Civil and Environmental Engineering, Texas A and M University, College Station, TX 77843-3136 (United States)

2008-05-15

Mutagenesis of Escherichia coli for hydrogen production is difficult since there is no high-throughput screen. Here we describe a method for rapid detection of enhanced hydrogen production by engineered strains by detecting formate via potassium permanganate; in E. coli, hydrogen is synthesized from formate using the formate hydrogen lyase system. (author)

Hydrogen production from rice winery wastewater in an upflow anaerobic reactor by using mixed anaerobic cultures

Energy Technology Data Exchange (ETDEWEB)

Hanqing Yu; Zhenhu Zhu [University of Science and Technology, Hefei, Anhui (China). School of Chemistry and Materials; Wenrong Hu [Shandong Univ., Jinan (China). School of Resources and Environmental Engineering; Haisheng Zhang [Jingzi Wine Distillery Company, Shandong (China)

2002-12-01

Continuous production of hydrogen from the anaerobic acidogenesis of a high-strength rice winery wastewater by a mixed bacterial flora was demonstrated. The experiment was conducted in a 3.0-l upflow reactor to investigate individual effects of hydraulic retention time (HRT) (2-24 h), chemical oxygen demand (COD) concentration in wastewater (14-36 g COD/l), pH (4.5-6.0) and temperature (20-55{sup o}C) on bio-hydrogen production from the wastewater. The biogas produced under all test conditions was composed of mostly hydrogen (53-61%) and carbon dioxide (37-45%), but contained no detectable methane. Specific hydrogen production rate increased with wastewater concentration and temperature, but with a decrease in HRT. An optimum hydrogen production rate of 9.33 lH{sub 2}/gVSSd was achieved at an HRT of 2 h, COD of 34 g/l, pH 5.5 and 55{sup o}C. The hydrogen yield was in the range of 1.37-2.14 mol/mol-hexose. In addition to acetate, propionate and butyrate, ethanol was also present in the effluent as an aqueous product. The distribution of these compounds in the effluent was more sensitive to wastewater concentration, pH and temperature, but was less sensitive to HRT. This upflow reactor was shown to be a promising biosystem for hydrogen production from high-strength wastewaters by mixed anaerobic cultures. (Author)

Efficient Production of Hydrogen from Decomposition of Formic Acid over Zeolite Incorporated Gold Nanoparticles

DEFF Research Database (Denmark)

Gallas-Hulin, Agata; Mielby, Jerrik Jørgen; Kegnæs, Søren

2016-01-01

Formic acid has a great potential as a safe and convenient source of hydrogen for sustainable chemical synthesis and renewable energy storage. Here, we report a heterogeneous gold nanoparticles catalyst for efficient production of hydrogen from vapor phase decomposition of formic acid using zeolite...... incorporated gold nanoparticles. The catalyst is prepared by pressure assisted impregnation and reduction (PAIR), which results in a uniform distribution of small gold nanoparticles that are incorporated into zeolite silicalite-1 crystals. Consequently, the incorporated nanoparticles exhibit increased...... sintering stability. Based on these results, we believe that incorporation of metal nanoparticles in zeolites may find use as highly active and selective heterogeneous catalysts for the production of hydrogen in future renewable energy applications....

Influence of acidic pH on hydrogen and acetate production by an electrosynthetic microbiome.

Directory of Open Access Journals (Sweden)

Edward V LaBelle

Full Text Available Production of hydrogen and organic compounds by an electrosynthetic microbiome using electrodes and carbon dioxide as sole electron donor and carbon source, respectively, was examined after exposure to acidic pH (∼ 5. Hydrogen production by biocathodes poised at -600 mV vs. SHE increased >100-fold and acetate production ceased at acidic pH, but ∼ 5-15 mM (catholyte volume/day acetate and >1,000 mM/day hydrogen were attained at pH ∼ 6.5 following repeated exposure to acidic pH. Cyclic voltammetry revealed a 250 mV decrease in hydrogen overpotential and a maximum current density of 12.2 mA/cm2 at -765 mV (0.065 mA/cm2 sterile control at -800 mV by the Acetobacterium-dominated community. Supplying -800 mV to the microbiome after repeated exposure to acidic pH resulted in up to 2.6 kg/m3/day hydrogen (≈ 2.6 gallons gasoline equivalent, 0.7 kg/m3/day formate, and 3.1 kg/m3/day acetate ( = 4.7 kg CO2 captured.

Efficiency of hydrogen gas production in a stand-alone solar hydrogen system

International Nuclear Information System (INIS)

Singh, K.; Tamakloe, R.Y.

2003-01-01

Many photovoltaic systems operate in a decentralised electricity producing system, or stand-alone mode and the total energy demand is met by the output of the photovoltaic array. The output of the photovoltaic system fluctuates and is unpredictable for many applications making some forms of energy storage system necessary. The role of storage medium is to store the excess energy produced by the photovoltaic arry, to absorb momentary power peaks and to supply energy during sunless periods. One of the storage modes is the use of electrochemical techniques, with batteries and water electrolysis as the most important examples. The present study includes three main parts: the first one is the hydrogen production form the electrolysis of water depending on the DC output current of the photovoltaic (PV) energy source and the charging of the battery. The second part presents the influence of various parameters on the efficiency of hydrogen gas production. The final part includes simulation studies with focus on solar hydrogen efficiency under the influence of various physical and chemical parameters. For a 50W panel-battery-electrolyser system, the dependence of volume of hydrogen gas on voltage, current and power yielded a maximum efficiency of 13.6% (author)

Estimating Hydrogen Production Potential in Biorefineries Using Microbial Electrolysis Cell Technology

Energy Technology Data Exchange (ETDEWEB)

Borole, Abhijeet P [ORNL; Mielenz, Jonathan R [ORNL

2011-01-01

Microbial electrolysis cells (MECs) are devices that use a hybrid biocatalysis-electrolysis process for production of hydrogen from organic matter. Future biofuel and bioproducts industries are expected to generate significant volumes of waste streams containing easily degradable organic matter. The emerging MEC technology has potential to derive added- value from these waste streams via production of hydrogen. Biorefinery process streams, particularly the stillage or distillation bottoms contain underutilized sugars as well as fermentation and pretreatment byproducts. In a lignocellulosic biorefinery designed for producing 70 million gallons of ethanol per year, up to 7200 m3/hr of hydrogen can be generated. The hydrogen can either be used as an energy source or a chemical reagent for upgrading and other reactions. The energy content of the hydrogen generated is sufficient to meet 57% of the distillation energy needs. We also report on the potential for hydrogen production in existing corn mills and sugar-based biorefineries. Removal of the organics from stillage has potential to facilitate water recycle. Pretreatment and fermentation byproducts generated in lignocellulosic biorefinery processes can accumulate to highly inhibitory levels in the process streams, if water is recycled. The byproducts of concern including sugar- and lignin- degradation products such as furans and phenolics can also be converted to hydrogen in MECs. We evaluate hydrogen production from various inhibitory byproducts generated during pretreatment of various types of biomass. Finally, the research needs for development of the MEC technology and aspects particularly relevant to the biorefineries are discussed.

HYDROGEN PRODUCTION BY THE CYANOBACTERIUM PLECTONEMA BORYANUM: EFFECTS OF INITIAL NITRATE CONCENTRATION, LIGHT INTENSITY, AND INHIBITION OF PHOTOSYSTEM II BY DCMU

Energy Technology Data Exchange (ETDEWEB)

Carter, B.; Huesemann, M.

2008-01-01

The alarming rate at which atmospheric carbon dioxide levels are increasing due to the burning of fossil fuels will have incalculable consequences if disregarded. Fuel cells, a source of energy that does not add to carbon dioxide emissions, have become an important topic of study. Although signifi cant advances have been made related to fuel cells, the problem of cheap and renewable hydrogen production still remains. The cyanobacterium Plectonema boryanum has demonstrated potential as a resolution to this problem by producing hydrogen under nitrogen defi cient growing conditions. Plectonema boryanum cultures were tested in a series of experiments to determine the effects of light intensity, initial nitrate concentration, and photosystem II inhibitor DCMU (3-(3,4- dichlorophenyl)-1,1-dimethylurea) upon hydrogen production. Cultures were grown in sterile Chu. No. 10 medium within photobioreactors constantly illuminated by halogen lights. Because the enzyme responsible for hydrogen production is sensitive to oxygen, the medium was continuously sparged with argon/CO2 (99.7%/0.3% vol/vol) by gas dispersion tubes immersed in the culture. Hydrogen production was monitored by using a gas chromatograph equipped with a thermal conductivity detector. In the initial experiment, the effects of initial nitrate concentration were tested and results revealed cumulative hydrogen production was maximum at an initial nitrate concentration of 1 mM. A second experiment was then conducted at an initial nitrate concentration of 1 mM to determine the effects of light intensity at 50, 100, and 200 μmole m-2 s-1. Cumulative hydrogen production increased with increasing light intensity. A fi nal experiment, conducted at an initial nitrate concentration of 2 mM, tested the effects of high light intensity at 200 and 400 μmole m-2 s-1. Excessive light at 400 μmole m-2 s-1 decreased cumulative hydrogen production. Based upon all experiments, cumulative hydrogen production rates were optimal

Fermentative hydrogen production from Jerusalem artichoke by Clostridium tyrobutyricum expressing exo-inulinase gene.

Science.gov (United States)

Jiang, Ling; Wu, Qian; Xu, Qing; Zhu, Liying; Huang, He

2017-08-11

Clostridium tyrobutyricum ATCC25755 has been reported as being able to produce significant quantities of hydrogen. In this study, the exo-inulinase encoding gene cloned from Paenibacillus polymyxa SC-2 was into the expression plasmid pSY6 and expressed in the cells of C. tyrobutyricum. The engineered C. tyrobutyricum strain efficiently fermented the inulin-type carbohydrates from Jerusalem artichoke, without any pretreatment being necessary for the production of hydrogen. A comparatively high hydrogen yield (3.7 mol/mol inulin-type sugar) was achieved after 96 h in a batch process with simultaneous saccharification and fermentation (SSF), with an overall volumetric productivity rate of 620 ± 60 mL/h/L when the initial total sugar concentration of the inulin extract was increased to 100 g/L. Synthesis of inulinase in the batch SSF culture was closely associated with strain growth until the end of the exponential phase, reaching a maximum activity of 28.4 ± 0.26 U/mL. The overall results show that the highly productive and abundant biomass crop Jerusalem artichoke can be a good substrate for hydrogen production, and that the application of batch SSF for its conversion has the potential to become a cost-effective process in the near future.

Universally applicable design concept of stably controlling an HTGR-hydrogen production system

International Nuclear Information System (INIS)

Hada, Kazuhiko; Shibata, Taiju; Nishihara, Tetsuo; Shiozawa, Shusaku

1996-01-01

An HTGR-hydrogen production system should be designed to have stable controllability because of a large difference in thermal dynamics between reactor and hydrogen production system and such a control design concept should be universally applicable to a variety of hydrogen production processes by the use of nuclear heat from HTGR. A transient response analysis of an HTGR-steam reforming hydrogen production system showed that a steam generator installed in a helium circuit for cooling the nuclear reactor provides stable controllability of the total system, resulting in avoiding a reactor scram. A survey of control design-related characteristics among several hydrogen production processes revealed the similarity of endothermic chemical reactions by the use of high temperature heat and that steam is required as a reactant of the endothermic reaction or for preheating a reactant. Based on these findings, a system design concept with stable controllability and universal applicability was proposed to install a steam generator as a downstream cooler of an endothermic reactor in the helium circuit of an HTGR-hydrogen production system. (author)

Microbial Fe (III) reduction and hydrogen production by a transposon-mutagenized strain of Pantoea agglomerans BH18

International Nuclear Information System (INIS)

Liu, Hongyan; Wang, Guangce

2015-01-01

Based on the transposon-mutagenized library of Pantoea agglomerans BH18, mutant screens were conducted to obtain the strain with the highest Fe (III) reduction and hydrogen production. Of these transposon-mutagenized mutants, the mutant strain TB230 was screened for high Fe (III)-reducing efficiency and hydrogen production. The PCR amplification and kanamycin resistance selection results indicated that the transposon insertion of the mutant strain TB230 was stable. Hydrogen production of the mutant strain TB230 was (2.21 ± 0.34) mol H 2 /mol glucose, which increased hydrogen production by over 40% compared with that of the wild type strain. The accumulation concentration of Fe (II) in the medium of the mutant strain TB230 with Fe (OH) 3 as the sole electron acceptor was (7.39 ± 0.49) mmol/l, which was approximately 3-fold greater than that of the wild type strain. The mutant strain TB230 showed high Fe (III)-reducing activity and hydrogen production by adopting glucose and pyruvate as the carbon source. In addition, the mutant strain TB230 was capable of Fe (III) reduction and hydrogen production under fresh or marine conditions. This result indicates that the mutant strain with high microbial Fe (III) reduction and hydrogen production is beneficial for the improvement of anaerobic performance. - Highlights: • The mutant strain TB230 was a transposon-mutagenized strain of Pantoea agglomerans BH18. • Strain TB230 was screened for high Fe (III)-reducing efficiency and hydrogen production. • H 2 yield and Fe (III)-reducing activity were 2.21 ± 0.34 and 7.39 ± 0.49 in marine condition. • Strain TB230 was capable of Fe (III) reduction and hydrogen production in fresh or marine condition

Microbial Electrolysis Cells for High Yield Hydrogen Gas Production from Organic Matter

KAUST Repository

Logan, Bruce E.

2008-12-01

The use of electrochemically active bacteria to break down organic matter, combined with the addition of a small voltage (>0.2 V in practice) in specially designed microbial electrolysis cells (MECs), can result in a high yield of hydrogen gas. While microbial electrolysis was invented only a few years ago, rapid developments have led to hydrogen yields approaching 100%, energy yields based on electrical energy input many times greater than that possible by water electrolysis, and increased gas production rates. MECs used to make hydrogen gas are similar in design to microbial fuel cells (MFCs) that produce electricity, but there are important differences in architecture and analytical methods used to evaluate performance. We review here the materials, architectures, performance, and energy efficiencies of these MEC systems that show promise as a method for renewable and sustainable energy production, and wastewater treatment. © 2008 American Chemical Society.

Hydrogen Production Costs of Various Primary Energy Sources

International Nuclear Information System (INIS)

Choi, Jae Hyuk; Tak, Nam Il; Kim, Yong Hee; Park, Won Seok

2005-01-01

The limited resource and environmental impacts of fossil fuels are becoming more and more serious problems in the world. Consequently, hydrogen is in the limelight as a future alternative energy due to its clean combustion and inexhaustibility and a transition from the traditional fossil fuel system to a hydrogen-based energy system is under considerations. Several countries are already gearing the industries to the hydrogen economy to cope with the limitations of the current fossil fuels. Unfortunately, hydrogen has to be chemically separated from the hydrogen compounds in nature such as water by using some energy sources. In this paper, the hydrogen production costs of major primary energy sources are compared in consideration of the Korean situations. The evaluation methodology is based on the report of the National Academy of Science (NAS) of U.S

Cea assessment of the sulphur-iodine cycle for hydrogen production

International Nuclear Information System (INIS)

Caries, Ph.; Vitart, X.; Yvon, P.

2010-01-01

The sulphur-iodine cycle is a promising process for hydrogen production using nuclear heat: - it is a purely thermochemical cycle, implying that hydrogen production will scale with volume rather than surface; - it only involves fluids, thus avoiding the often difficult handling of solids; - its heat requirements are well matched to the temperatures available from a Generation IV very/high temperature reactor. These characteristics seem very attractive for high efficiency and low cost massive hydrogen production. On the other hand, the efficiency of the cycle may suffer from the large over-stoichiometries of water and iodine and the very important heat exchanges it involves; furthermore, due to lack of adequate thermodynamic models, its efficiency is difficult to assess with confidence. Besides, the large quantities of chemicals that need to be handled, and the corrosiveness of these chemicals, are factors not to be overlooked in terms of investment and operation costs. In order to assess the actual potential of the sulphur-iodine cycle for massive hydrogen production at a competitive cost, CEA has been conducting an important programme on this cycle, ranging from thermodynamic measurements to hydrogen production cost evaluation, with flow sheet optimisation, component sizing and investment cost estimation as intermediate steps. The paper will present the method used, the status of both efficiency and production cost estimations, and discuss perspectives for improvement. (authors)

Enhanced Bio-hydrogen Production from Protein Wastewater by Altering Protein Structure and Amino Acids Acidification Type

Science.gov (United States)

Xiao, Naidong; Chen, Yinguang; Chen, Aihui; Feng, Leiyu

2014-01-01

Enhanced bio-hydrogen production from protein wastewater by altering protein structure and amino acids acidification type via pH control was investigated. The hydrogen production reached 205.2 mL/g-protein when protein wastewater was pretreated at pH 12 and then fermented at pH 10. The mechanism studies showed that pH 12 pretreatment significantly enhanced protein bio-hydrolysis during the subsequent fermentation stage as it caused the unfolding of protein, damaged the protein hydrogen bonding networks, and destroyed the disulfide bridges, which increased the susceptibility of protein to protease. Moreover, pH 10 fermentation produced more acetic but less propionic acid during the anaerobic fermentation of amino acids, which was consistent with the theory of fermentation type affecting hydrogen production. Further analyses of the critical enzymes, genes, and microorganisms indicated that the activity and abundance of hydrogen producing bacteria in the pH 10 fermentation reactor were greater than those in the control. PMID:24495932

Enhanced bio-hydrogen production from protein wastewater by altering protein structure and amino acids acidification type.

Science.gov (United States)

Xiao, Naidong; Chen, Yinguang; Chen, Aihui; Feng, Leiyu

2014-02-05

Enhanced bio-hydrogen production from protein wastewater by altering protein structure and amino acids acidification type via pH control was investigated. The hydrogen production reached 205.2 mL/g-protein when protein wastewater was pretreated at pH 12 and then fermented at pH 10. The mechanism studies showed that pH 12 pretreatment significantly enhanced protein bio-hydrolysis during the subsequent fermentation stage as it caused the unfolding of protein, damaged the protein hydrogen bonding networks, and destroyed the disulfide bridges, which increased the susceptibility of protein to protease. Moreover, pH 10 fermentation produced more acetic but less propionic acid during the anaerobic fermentation of amino acids, which was consistent with the theory of fermentation type affecting hydrogen production. Further analyses of the critical enzymes, genes, and microorganisms indicated that the activity and abundance of hydrogen producing bacteria in the pH 10 fermentation reactor were greater than those in the control.

Cost Evaluation with G4-ECONS Program for SI based Nuclear Hydrogen Production Plant

International Nuclear Information System (INIS)

Kim, Jong-ho; Lee, Ki-young; Kim, Yong-wan

2014-01-01

Contemporary hydrogen is production is primarily based on fossil fuels, which is not considered as environments friendly and economically efficient. To achieve the hydrogen economy, it is very important to produce a massive amount of hydrogen in a clean, safe and efficient way. Nuclear production of hydrogen would allow massive production of hydrogen at economic prices while avoiding environments pollution reducing the release of carbon dioxide. Nuclear production of hydrogen could thus become the enabling technology for the hydrogen economy. The economic assessment was performed for nuclear hydrogen production plant consisting of VHTR coupled with SI cycle. For the study, G4-ECONS developed by EMWG of GIF was appropriately modified to calculate the LUHC, assuming 36 months of plant construction time, 5 % of annual interest rate and 12.6 % of fixed charge rate. In G4-ECONS program, LUHC is calculated by the following formula; LUHC = (Annualized TCIC + Annualized O-M Cost + Annualized Fuel Cycle Cost + Annualized D-D Cost) / Annual Hydrogen Production Rate

Coupling the modular helium reactor to hydrogen production processes

International Nuclear Information System (INIS)

Richards, M.B.; Shenoy, A.S.; Schultz, K.R.

2004-01-01

Steam reforming of natural gas (methane) currently produces the bulk of hydrogen gas used in the world today. Because this process depletes natural gas resources and generates the greenhouse gas carbon dioxide as a by-product, there is a growing interest in using process heat and/or electricity generated by nuclear reactors to generate hydrogen by splitting water. Process heat from a high temperature nuclear reactor can be used directly to drive a set of chemical reactions, with the net result of splitting water into hydrogen and oxygen. For example, process heat at temperatures in the range 850 deg C to 950 deg C can drive the sulphur-iodine (S-I) thermochemical process to produce hydrogen with high efficiency. The S-I process produces highly pure hydrogen and oxygen, with formation, decomposition, regeneration, and recycle of the intermediate chemical reagents. Electricity can also 1)e used directly to split water, using conventional, low-temperature electrolysis (LTE). Hydrogen can also be produced with hybrid processes that use both process heat and electricity to generate hydrogen. An example of a hybrid process is high-temperature electrolysis (HTE), in which process heat is used to generate steam, which is then supplied to an electrolyzer to generate hydrogen. This process is of interest because the efficiency of electrolysis increases with temperature. Because of its high temperature capability, advanced stage of development relative to other high-temperature reactor concepts, and passive-safety features, the modular helium reactor (MHR) is well suited for producing hydrogen using nuclear energy. In this paper we investigate the coupling of the MHR to the S-I process, LTE, and HTE. These concepts are referred to as the H2-MHR. (author)

Safety considerations for continuous hydrogen production test apparatus with capacity of 50 N-litter hydrogen per hour

International Nuclear Information System (INIS)

Onuki, Kaoru; Akino, Norio; Shimizu, Saburo; Nakajima, Hayato; Higashi, Shunichi; Kubo, Shinji

2001-03-01

Since the thermochemical hydrogen production Iodine-Sulfur process decomposes water into hydrogen and oxygen using toxic chemicals such as sulfuric acid, iodine and hydriodic acid, safety considerations are very important in its research and development. Therefore, before construction of continuous hydrogen production test apparatus with capacity of 50 N-litter hydrogen per hour, comprehensive safety considerations were carried out to examine the design and construction works of the test apparatus, and the experimental plans using the apparatus. Emphasis was given on the safety considerations on prevention of breakage of glasswares and presumable abnormalities, accidents and their countermeasures. This report summarizes the results of the considerations. (author)

Hydrogen production from wastes. State-of-the-art and development potential. Final report

International Nuclear Information System (INIS)

Megret, O.; Hubert, L.; Calbry, M.; Trably, E.; Carrere, H.; Garcia-Bernet, D.; Bernet, N.

2015-09-01

Within the framework of the search for a virtuous energy system, the energy production known as 'clean' presents major stakes as well environmental as economic and societal. Among the potentially usable energy vectors, the dihydrogen gas proves to be a serious alternative to fossil energies. The 'traditional' production processes rest on extraction of hydrocarbon fossil resources and are strongly disparaged for their environmental impacts and the dependences with international access to fossil resources. To date, in addition to hydrogen production by water electrolysis based on renewable resources, the promising sectors of hydrogen production are those of the bio-refinery applied to layers of rough biomass, waste organic, sludges, etc. They involve both thermochemical and biological conversion processes. The objective of this study is to carry out a detailed state of the art of these alternative processes allowing the conversion of biomass-type wastes and by-products, on the scale of France, Europe and World. The study thus makes it possible to identify, describe and characterize the thermal and biological processes. The operating conditions to increase hydrogen production as well as the limits of the systems are presented: temperature, pressure, pH, quality of the layers, undesirable, gear robustness, etc. A brief study of the potential layers is proposed, making it possible to outline the potential of hydrogen production; however identification of the layers known as 'of implementation' (corresponding to the layers really expected taking into account the technical and economic context and of the competition of other valorization sectors) was not performed. For the thermal processes, theoretical examples of integrated processes are presented and an economic estimate of the hydrogen resulting cost is introduced. Regarding biological processes, the study identifies and analyses projects (on a pilot-scale for the most succeeded) which

Basic study on high temperature gas cooled reactor technology for hydrogen production

International Nuclear Information System (INIS)

Chang, Jong Hwa; Lee, W. J.; Lee, H. M.

2003-01-01

The annual production of hydrogen in the world is about 500 billion m 3 . Currently hydrogen is consumed mainly in chemical industries. However hydrogen has huge potential to be consumed in transportation sector in coming decades. Assuming that 10% of fossil energy in transportation sector is substituted by hydrogen in 2020, the hydrogen in the sector will exceed current hydrogen consumption by more than 2.5 times. Currently hydrogen is mainly produced by steam reforming of natural gas. Steam reforming process is chiefest way to produce hydrogen for mass production. In the future, hydrogen has to be produced in a way to minimize CO2 emission during its production process as well as to satisfy economic competition. One of the alternatives to produce hydrogen under such criteria is using heat source of high-temperature gas-cooled reactor. The high-temperature gas-cooled reactor represents one type of the next generation of nuclear reactors for safe and reliable operation as well as for efficient and economic generation of energy

Study of metabolic pathways for hydrogen production in chlamydomonas reinhardtii and transposition on a torus photo bioreactor; Etude des voies metaboliques de production d'hydrogene chez la microalgue Chlamydomonas reinhardtii et transposition en photobioreacteur

Energy Technology Data Exchange (ETDEWEB)

Fouchard, S

2006-04-15

Considering the recent increase in energy consumption. aide associated environmental risks, new trails are followed today to develop the use of clean and renewable alternative energies. In this context hydrogen seems to be a serious solution and this study, based on micro-algae photosynthetic capacities exploitation, will allow to devise a process for hydrogen production from only water and solar energy without greenhouse gas release. The sulphur deprivation protocol on TAP medium, known to lead to hydrogen production in Chlamydomonas reinhardtii species was particularly studied. At the metabolic level, two important phenomena are induced under these conditions: an over-accumulation of the intracellular starch reserves and a simultaneous alteration of the PsII activity which leads to anoxia and Fe-hydrogenase induction, an enzyme with a strong specific activity responsible for the hydrogen production. The contribution of the two electron transfer pathways implied in the hydrogen production process (PsII-dependent and PSII-independent) as well as the importance of the previously accumulated starch were highlighted here. We also investigated the potential for designing autotrophic protocols for hydrogen photoproduction. Various protocols, considered to be relevant, were then transposed on a torus photo-bioreactor, specifically developed in this study and which allows the control of culture parameters as well as the precise measurement of gas release kinetics, in order to obtain first estimates of productivity of the system. Integration of the physical; aspects of the pilot and biological aspects of the process in a model, finally opens new prospects for subject development, in particular for a reasoned optimization of hydrogen production via this double physiology/process approach. (author)

Hydrogen co-production from subcritical water-cooled nuclear power plants in Canada

Energy Technology Data Exchange (ETDEWEB)

Gnanapragasam, N.; Ryland, D.; Suppiah, S., E-mail: gnanapragasamn@aecl.ca [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada)

2013-06-15

Subcritical water-cooled nuclear reactors (Sub-WCR) operate in several countries including Canada providing electricity to the civilian population. The high-temperature-steam-electrolysis process (HTSEP) is a feasible and laboratory-demonstrated large-scale hydrogen-production process. The thermal and electrical integration of the HTSEP with Sub-WCR-based nuclear-power plants (NPPs) is compared for best integration point, HTSEP operating condition and hydrogen production rate based on thermal energy efficiency. Analysis on integrated thermal efficiency suggests that the Sub-WCR NPP is ideal for hydrogen co-production with a combined efficiency of 36%. HTSEP operation analysis suggests that higher product hydrogen pressure reduces hydrogen and integrated efficiencies. The best integration point for the HTSEP with Sub-WCR NPP is upstream of the high-pressure turbine. (author)

Recent advances on membranes and membrane reactors for hydrogen production

NARCIS (Netherlands)

Gallucci, F.; Fernandez Gesalaga, E.; Corengia, P.; Sint Annaland, van M.

2013-01-01

Membranes and membrane reactors for pure hydrogen production are widely investigated not only because of the important application areas of hydrogen, but especially because mechanically and chemically stable membranes with high perm-selectivity towards hydrogen are available and are continuously

Bio-hydrogen production from hyacinth by anaerobic fermentation

International Nuclear Information System (INIS)

Cheng Jun; Zhou Junhu; Qi Feng; Xie Binfei; Cen Kefa

2006-01-01

The bio-hydrogen production from hyacinth by anaerobic fermentation of digested sludge is studied in this paper. The compositions of bio-gases and volatile fatty acids in fermentation liquids are determined on TRACE 2000 gas chromatography. It is found that the H 2 concentration in the biogas is 10%-20% and no CH 4 is detected. The bio-hydrogen production from hyacinth with the initial pH value of 5.5 is higher than that with the initial pH value of 4.5. The fermentation temperature of 55 C is better than that of 35 C, while the weight ratio of hyacinth to microorganism of 1:1 is better than that of 3:7. The highest hydrogen production of 122.3 mL/g is obtained when the initial pH value of fermentation solution is 5.5, the fermentation temperature is 55 C and the weight ratio of hyacinth to microorganism is 1:1. (authors)

Accident sequences and causes analysis in a hydrogen production process

Energy Technology Data Exchange (ETDEWEB)

Jae, Moo Sung; Hwang, Seok Won; Kang, Kyong Min; Ryu, Jung Hyun; Kim, Min Soo; Cho, Nam Chul; Jeon, Ho Jun; Jung, Gun Hyo; Han, Kyu Min; Lee, Seng Woo [Hanyang Univ., Seoul (Korea, Republic of)

2006-03-15

Since hydrogen production facility using IS process requires high temperature of nuclear power plant, safety assessment should be performed to guarantee the safety of facility. First of all, accident cases of hydrogen production and utilization has been surveyed. Based on the results, risk factors which can be derived from hydrogen production facility were identified. Besides the correlation between risk factors are schematized using influence diagram. Also initiating events of hydrogen production facility were identified and accident scenario development and quantification were performed. PSA methodology was used for identification of initiating event and master logic diagram was used for selection method of initiating event. Event tree analysis was used for quantification of accident scenario. The sum of all the leakage frequencies is 1.22x10{sup -4} which is similar value (1.0x10{sup -4}) for core damage frequency that International Nuclear Safety Advisory Group of IAEA suggested as a criteria.

Study on hydrogen production using the fast breeder reactors (FBR)

International Nuclear Information System (INIS)

Kani, Yoshio

2003-01-01

As the fast breeder reactor (FBR) can effectively convert uranium-238 difficult to carry out nuclear fission at thermal neutron reactors to nuclear fissionable plutonium-239 to use it remarkable upgrading of application on uranium can be performed, to be expected for sustainable energy source. And, by reuse minor actinides of long half-life nuclides in reprocessed high level wasted solutions for fuels of nuclear reactors, reduction of radioactive poison based on high level radioactive wastes was enabled. As high temperature of about 800 centigrade was required on conventional hydrogen production, by new hydrogen production technique even at operation temperature of sodium-cooled FBR it can be enabled. Here were described for new hydrogen production methods applicable to FBR on palladium membrane hydrogen separation method carrying out natural gas/steam modification at reaction temperature of about 500 centigrade, low temperature thermo-chemical method expectable simultaneous simplification of production process, and electrolysis method expected on power load balancing. (G.K.)

Why hydrogen; Pourquoi l'hydrogene?

Energy Technology Data Exchange (ETDEWEB)

NONE

2004-02-01

The energy consumption increase and the associated environmental risks, led to develop new energy sources. The authors present the potentialities of the hydrogen in this context of energy supply safety. They detail the today market and the perspectives, the energy sources for the hydrogen production (fossils, nuclear and renewable), the hydrogen transport, storage, distribution and conversion, the application domains, the associated risks. (A.L.B.)

Carbon-free hydrogen production from low rank coal

Science.gov (United States)

Aziz, Muhammad; Oda, Takuya; Kashiwagi, Takao

2018-02-01

Novel carbon-free integrated system of hydrogen production and storage from low rank coal is proposed and evaluated. To measure the optimum energy efficiency, two different systems employing different chemical looping technologies are modeled. The first integrated system consists of coal drying, gasification, syngas chemical looping, and hydrogenation. On the other hand, the second system combines coal drying, coal direct chemical looping, and hydrogenation. In addition, in order to cover the consumed electricity and recover the energy, combined cycle is adopted as addition module for power generation. The objective of the study is to find the best system having the highest performance in terms of total energy efficiency, including hydrogen production efficiency and power generation efficiency. To achieve a thorough energy/heat circulation throughout each module and the whole integrated system, enhanced process integration technology is employed. It basically incorporates two core basic technologies: exergy recovery and process integration. Several operating parameters including target moisture content in drying module, operating pressure in chemical looping module, are observed in terms of their influence to energy efficiency. From process modeling and calculation, two integrated systems can realize high total energy efficiency, higher than 60%. However, the system employing coal direct chemical looping represents higher energy efficiency, including hydrogen production and power generation, which is about 83%. In addition, optimum target moisture content in drying and operating pressure in chemical looping also have been defined.

Large-scale hydrogen production using nuclear reactors

Energy Technology Data Exchange (ETDEWEB)

Ryland, D.; Stolberg, L.; Kettner, A.; Gnanapragasam, N.; Suppiah, S. [Atomic Energy of Canada Limited, Chalk River, ON (Canada)

2014-07-01

For many years, Atomic Energy of Canada Limited (AECL) has been studying the feasibility of using nuclear reactors, such as the Supercritical Water-cooled Reactor, as an energy source for large scale hydrogen production processes such as High Temperature Steam Electrolysis and the Copper-Chlorine thermochemical cycle. Recent progress includes the augmentation of AECL's experimental capabilities by the construction of experimental systems to test high temperature steam electrolysis button cells at ambient pressure and temperatures up to 850{sup o}C and CuCl/HCl electrolysis cells at pressures up to 7 bar and temperatures up to 100{sup o}C. In parallel, detailed models of solid oxide electrolysis cells and the CuCl/HCl electrolysis cell are being refined and validated using experimental data. Process models are also under development to assess options for economic integration of these hydrogen production processes with nuclear reactors. Options for large-scale energy storage, including hydrogen storage, are also under study. (author)

Construction apparatus for thermochemical hydrogen production process

Energy Technology Data Exchange (ETDEWEB)

Kubo, S.; Nakajima, H.; Higashi, S.; Onuki, K.; Akino, S.S.N. [Japan Atomic Energy Research Inst., Ibaraki-ken (Japan). Nuclear Heat Utilization Engineering Lab

2001-06-01

Studies have been carried out at the Japan Atomic Energy Research Institute (JAERI) on hydrogen production through thermochemical processes such as water-splitting. These studies are classified with iodine-sulphur cycle studies using heat from high temperature gas-cooled reactors. An experimental apparatus was constructed with fluorine resin, glass and quartz. It can produce hydrogen at a rate of 50 litres per hour. Electricity provides the heat required for the operation. The closed chemical process requires special control techniques. The process flow diagram for the apparatus was designed based on the results of previous studies including one where hydrogen production was successfully achieved at a rate of one liter per hour for 48 hours. Experimental operations under atmospheric pressure will be carried out for the next four years to develop the process. The data will be used in the next research and development programs aimed at designing a bench-scale apparatus. 7 refs., 1 tab., 8 figs.

Comparative environmental impact and efficiency assessment of selected hydrogen production methods

Energy Technology Data Exchange (ETDEWEB)

Ozbilen, Ahmet, E-mail: Ahmet.Ozbilen@uoit.ca; Dincer, Ibrahim, E-mail: Ibrahim.Dincer@uoit.ca; Rosen, Marc A., E-mail: Marc.Rosen@uoit.ca

2013-09-15

The environmental impacts of various hydrogen production processes are evaluated and compared, considering several energy sources and using life cycle analysis. The results indicate that hydrogen produced by thermochemical water decomposition cycles are more environmentally benign options compared to conventional steam reforming of natural gas. The nuclear based four-step Cu–Cl cycle has the lowest global warming potential (0.559 kg CO{sub 2}-eq per kg hydrogen production), mainly because it requires the lowest quantity of energy of the considered processes. The acidification potential results show that biomass gasification has the highest impact on environment, while wind based electrolysis has the lowest. The relation is also investigated between efficiency and environmental impacts. -- Highlights: • Environmental performance of nuclear-based hydrogen production is investigated. • The GWP and AP results are compared with various hydrogen production processes. • Nuclear based 4-step Cu–Cl cycle is found to be an environmentally benign process. • Wind-based electrolysis has the lowest AP value.

Decentralized production of hydrogen from hydrocarbons with reduced CO2 emission

International Nuclear Information System (INIS)

Nazim Muradov; Franklyn Smith; Cunping Huang; Ali T-Raissi

2006-01-01

Currently, most of the industrial hydrogen production is based on steam methane reforming process that releases significant amount of CO 2 into the atmosphere. CO 2 sequestration is one approach to solving the CO 2 emission problem for large centralized hydrogen plants, but it would be impractical for decentralized H 2 production units. The objective of this paper is to explore new routes to hydrogen production from natural gas without (or drastically reduced) CO 2 emissions. One approach analyzed in this paper is based on thermo-catalytic decomposition (TCD) of hydrocarbons (e.g., methane) to hydrogen gas and elemental carbon. The paper discusses some technological aspects of the TCD process development: (1) thermodynamic analysis of TCD using AspenPlus chemical process simulator, (2) heat input options to the endothermic process, (3) catalyst activity issues, etc. Production of hydrogen and carbon via TCD of methane was experimentally verified using carbon-based catalysts. (authors)

Improving hydrogen production from cassava starch by combination of dark and photo fermentation

Energy Technology Data Exchange (ETDEWEB)

Su, Huibo; Cheng, Jun; Zhou, Junhu; Song, Wenlu; Cen, Kefa [State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027 (China)

2009-02-15

The combination of dark and photo fermentation was studied with cassava starch as the substrate to increase the hydrogen yield and alleviate the environmental pollution. The different raw cassava starch concentrations of 10-25 g/l give different hydrogen yields in the dark fermentation inoculated with the mixed hydrogen-producing bacteria derived from the preheated activated sludge. The maximum hydrogen yield (HY) of 240.4 ml H{sub 2}/g starch is obtained at the starch concentration of 10 g/l and the maximum hydrogen production rate (HPR) of 84.4 ml H{sub 2}/l/h is obtained at the starch concentration of 25 g/l. When the cassava starch, which is gelatinized by heating or hydrolyzed with {alpha}-amylase and glucoamylase, is used as the substrate to produce hydrogen, the maximum HY respectively increases to 258.5 and 276.1 ml H{sub 2}/g starch, and the maximum HPR respectively increases to 172 and 262.4 ml H{sub 2}/l/h. Meanwhile, the lag time ({lambda}) for hydrogen production decreases from 11 h to 8 h and 5 h respectively, and the fermentation duration decreases from 75-110 h to 44-68 h. The metabolite byproducts in the dark fermentation, which are mainly acetate and butyrate, are reused as the substrates in the photo fermentation inoculated with the Rhodopseudomonas palustris bacteria. The maximum HY and HPR are respectively 131.9 ml H{sub 2}/g starch and 16.4 ml H{sub 2}/l/h in the photo fermentation, and the highest utilization ratios of acetate and butyrate are respectively 89.3% and 98.5%. The maximum HY dramatically increases from 240.4 ml H{sub 2}/g starch only in the dark fermentation to 402.3 ml H{sub 2}/g starch in the combined dark and photo fermentation, while the energy conversion efficiency increases from 17.5-18.6% to 26.4-27.1% if only the heat value of cassava starch is considered as the input energy. When the input light energy in the photo fermentation is also taken into account, the whole energy conversion efficiency is 4.46-6.04%. (author)