水素エネルギーシステム
Online ISSN : 2436-5599
Print ISSN : 1341-6995
30 巻, 2 号
選択された号の論文の21件中1~21を表示しています
巻頭言
特集
  • 池谷 知彦
    2005 年30 巻2 号 p. 2-9
    発行日: 2005年
    公開日: 2022/04/11
    研究報告書・技術報告書 フリー

    NEDO has been promoting national projects for R&D of fuel cell and hydrogen energy technologies to commercialize FC systems for hydrogen energy economy. Until the past March 2005, review and modification of codes & standards and regulations had been completed to commercialization and popularization of FC vehicles, FC co-generation systems and hydrogen refilling stations. In 2005, NEDO has launched new projects to research and develop PEFC technologies, and to propose measurement methods and collect the data for establishment of C&S and regulations in order to accelerate commercialization. Especially, NEDO coordinates new schemes in these projects. One consortium tries to study and clarify fuel cell basic reaction and degradation mechanisms to prolong lifetime and create a new break-through technology. Another, which consists with system and material manufactures and energy supply companies, focuses the robust technology for new type PEFC systems operating around 100 degrees. And the other consortium of five system manufactures carries out R&D of BOP for PEFC stationary system in order to enhance durability and reduce cost in cooperation with BOP manufactures. It is very important to estimate the performance of hydrogen energy as the secondary energy converted from the primary energy sources, and discuss the scenario to R&D hydrogen and FC technologies for hydrogen energy economy.

  • 伊藤 芳輝, 植田 秀作
    2005 年30 巻2 号 p. 10-15
    発行日: 2005年
    公開日: 2022/04/11
    研究報告書・技術報告書 フリー

    To boost up the market of the fuel cell vehicle, the state of art technology for manufacturing high pressure hydrogen compressor, as well as growth of refuelling stations is highly required. It was believed that the development of the piston type high pressure hydrogen compressor is technically difficult. Newly developed high pressure non-lubricated piston type compressor (discharge pressure of 110MPa) manufactured by us has been supplied to a research institute which conducts the studies for the safeness of 70MPa fuel cell vehicle and its related equipment.

  • 上條 謙二郎
    2005 年30 巻2 号 p. 16-22
    発行日: 2005年
    公開日: 2022/04/11
    研究報告書・技術報告書 フリー

    Liquid hydrogen has properties of low temperature, low density, low viscosity, high compres-sibility, a high sensitivity of vapor pressure to temperature, etc.. The liquid hydrogen requires a high speed impeller because of its low density. Its low viscosity raises pump efficiency, on the othe hand , it often causes shaft vibrations of large amplitude due to small damping. To design and operate the liquid hydrogen pump, properties of liquid hydrogen shoud thoroughly be taken into consideration.

  • 吉田 幸孝
    2005 年30 巻2 号 p. 23-34
    発行日: 2005年
    公開日: 2022/04/11
    研究報告書・技術報告書 フリー

    A valve is necessary for supply of water, sewage, pipe gas, liquefied petroleum gas, gasoline, light oil, and also for fueling industrial plants, whether the state of gas is vapor or liquid. The type and structure of valve varies from one application to another, and valves are roughly categorized into three types: globe valve, gate valve, ball valve, and butterfly valve. If classified by operation method, they are divided into self-operation type and actuator-operation type. Moreover, if classified by purpose, they are divided into stop valve, pressure-reducing valve, safety valve, etc. Although there is especially no classification of valve by the type of fluid, it matters what type of material is to be used for what part of the valve: what type of metal should be used for valve body and what type of material should be used for sealing. In this sense, the specification of hydrogen valve is special. In case of valve for compressed hydrogen, its structure and material is specially designed and selected for brittleness of compressed hydrogen, and in case of valve for liquefied hydrogen, its structure and material is so specially designed and selected that it can be used under cryogenic condition..

  • 北口 久雄
    2005 年30 巻2 号 p. 35-40
    発行日: 2005年
    公開日: 2022/04/11
    研究報告書・技術報告書 フリー

    The hydrogen gas sensor has been playing an important role in the safety of various industries, which utilize high pressure hydrogen gas. But now, the better efficiency of hydrogen sensor is strongly hoped for the future “Hydrogen Society”. In this paper, hydrogen sensors which are actually used in various industries are described, namely the catalytic combustion, the hot-wire semiconductor and the thermal conductivity type. Furthermore, the new type hydrogen sensors, the solid-electrolyte, metal oxide semiconductor and other types, are also explained.

  • 大盛 幹士, 久和野 敏明, 児島 伸之
    2005 年30 巻2 号 p. 41-44
    発行日: 2005年
    公開日: 2022/04/11
    研究報告書・技術報告書 フリー

    TAIYO NIPPON SANSO has produced many hydrogen dispensers for hydrogen refueling stations, joining to the national project on the Hydrogen and Fuel cell-related. Selection criterion for components and safety measures for the leakage are explained on this literature. And the high-pressured gas control technology or the refueling control ,and the evolutionary process of the design of hydrogen dispensers are explained with the test results of the refueling control and some pictures of the dispensers ever installed.

  • 広瀬 雄彦, 小林 信夫, 森 大五郎
    2005 年30 巻2 号 p. 45-51
    発行日: 2005年
    公開日: 2022/04/11
    研究報告書・技術報告書 フリー

    Transport is consuming approximately one quarter of total energy consumption. Use of hydrogen to drive vehicles is very important for the realization of hydrogen society. However hydrogen characteristics make it quite difficult to store hydrogen on board, and a limited vehicle range makes a widespread use of the fuel cell vehicles difficult. This paper describes one effort to combine the classic metal hydride and the high pressure to improve the system storage density and summarizes the current efforts and a future potential of hydrogen storage technologies.

研究論文
  • 篠原 千明, 川上 智, 牧野 大作, 澤田 遼司, 山際 敦美, 林 弘, 杉山 茂, 斉藤 泰和
    2005 年30 巻2 号 p. 52-57
    発行日: 2005年
    公開日: 2022/04/11
    研究報告書・技術報告書 フリー

    The dehydrogenation of decalin to naphthalene has been investigated on Pt/C, Pt/Al2O3 and Pt/Al(OH)O catalysts to examine the effect of support and liquid-film conditions under reactive distillation conditions. The maximum conversion of decalin on Pt/C, which did not repel decalin, was observed at 483K under the conditions of 0.3g of the catalyst and 1ml of decalin, which were corresponded to the liquid-film conditions. The liquid-film conditions have been generally defined as the specific ratio of the catalyst weight and decalin volume at a reaction temperature greater than boiling point of decalin. However such a maximum was not observed on Pt/Al2O3 and Pt/Al(OH)O, which repelled decalin. Furthermore it was found that the reaction temperature, at which the maximum hydrogen evolution was observed, shifted from the boiling point of decalin to that of naphthalene with increasing the amount of naphthalene in the reaction solution, indicating that the control of the reaction temperature should be important factor to obtain the liquid film conditions.

  • 中原 真也, 城戸 裕之, 中島 健四郎
    2005 年30 巻2 号 p. 58-65
    発行日: 2005年
    公開日: 2022/04/11
    研究報告書・技術報告書 フリー

    It is important that the effect of dilution gas on the turbulent burning velocity of hydrogen mixtures is elucidated to develop modern hydrogen combustion devices. In our previous studies, the preferential diffusion effect was made clear to play an important role in the turbulent combustion characteristics, affecting the local burning velocity, where nitrogen was added as a dilution gas to several fuel/air mixtures. The present study is performed to obtain experimentally the turbulent combustion characteristics of dilution gas added lean hydrogen mixtures with special attention to the local burning velocity of turbulent flame, in order to elucidate the mechanism of turbulent combustion of those mixtures. In this study, the turbulent burning velocities of the prepared mixtures, whose laminar burning velocity were nearly the same and the equivalence ratio were varied, w ere experimentally investigated. Where, argon, helium and carbon dioxide in addition to nitrogen were adopted as dilution gas. It is found that carbon dioxide added mixtures show larger turbulent burning velocities than that of nitrogen added mixtures at the same equivalence ratio. On the contrary, helium added mixtures show very smaller turbulent burning velocities. Those characteristics are discussed in preferential diffusion effect, turbulent flame-front configurations and Markstein number.

  • 永井 二郎
    2005 年30 巻2 号 p. 66-71
    発行日: 2005年
    公開日: 2022/04/11
    研究報告書・技術報告書 フリー

    There is an optimum condition on water electrolysis efficiency due to effects of generated bubbles between electrodes. In this paper, in order to explain the existence of the optimum condition, a revised two-phase flow model of alkaline water electrolysis was explained. Bubble rising velocity between electrodes was assumed to be constant in the whole area. The model can express void fraction and current density profiles along electrodes, and show the existence of the optimum condition. In addition, the model exhibits the existence of water electrolysis limit where void fraction becomes almost 100% and water electrolysis can not be conducted. A non-dimensional parameter, Vn, was newly proposed that shows the degree of bubble packing between electrodes. For verification of this model, the optimum condition and the water electrolysis limit were measured during water electrolysis of KOH solution. The model predictions show good agreements with the experimental results.

    The experimental parameter in the presented model was only bubble rising velocity between electrodes, which is strongly affected by bubble diameter distribution. Therefore, in order to obtain basic information for modeling bubble departure criterion in the future, diameter distribution of departure bubbles on electrodes was measured using micro fiberscope. The obtained results show that mean diameter of departure bubbles increases as current density increases.

  • 稲葉 仁, 村田 和久, 斉藤 昌弘, 高原 功
    2005 年30 巻2 号 p. 72-77
    発行日: 2005年
    公開日: 2022/04/11
    研究報告書・技術報告書 フリー

    Hydrogen production by cellulose gasification over Ni catalysts was investigated. The catalytic activity and the kind of products were affected by the kind of supports. The use of simple metal oxides as supports resulted in a formation of much amount of tar or char, while the use of zeolites as supports could inhibit the formation of tar or char but promote the carbon deposition. The loading of Ce could inhibit the carbon deposition in some degree, and, as a result, the activity for hydrogen production over Ni/Ce/zeolite catalysts was found to be almost comparable to that of Rh/Ce/SiO2 catalyst. Thus, Ni/Ce/zeolite catalysts seem to be promising candidates for decomposition of cellulose, because Ni is cheaper than Rh.

  • 武野 計二, 岡林 一木, 一ノ瀬 利光, 河内 昭紀, 野中 剛, 橋口 和明, 千歳 敬子
    2005 年30 巻2 号 p. 78-82
    発行日: 2005年
    公開日: 2022/04/11
    研究報告書・技術報告書 フリー

    This paper describes the experimental investigation on the hypothetical dispersion and explosion of high-pressurized hydrogen gas which leaks through a nozzle of 10mm diameters with 40MPa pressure brown down to atmosphere. Since the distribution of dispersed hydrogen gas changes with time, concentration contours of every 1 second was measured by 15 sets of new device which consisted of 10 gas sensors. The explosion experiments were carried out with changing the time of ignition after the start of dispersion, and it was clarified that the explosion power depended not only on the concentration and volume of hydrogen/air pre-mixture, but also on the turbulence characteristics before ignition.

  • 杉山 渚, 豊田 昌宏, 天尾 豊
    2005 年30 巻2 号 p. 83-86
    発行日: 2005年
    公開日: 2022/04/11
    研究報告書・技術報告書 フリー

    Photoinduced hydrogen production with the system consisting of Mg chlorophyll-a (MgChl-a) from spirulina as a visible light photosensitizer, NADH, methylviologen (MV2+) and colloidal platinum in trimethyl alkyl bromide (CH3(CH2)nN(CH3)3+ . Br-; n=8, 12 and 14) micellar media was investigated. Consequently, the effective MV2+ photoreduction and hydrogen production systems were accomplished using MgChl-a in CH3(CH214N(CH3)3+ . Br- micellar media.

  • 仮屋 伸子, 福岡 淳, 市川 勝
    2005 年30 巻2 号 p. 87-90
    発行日: 2005年
    公開日: 2022/04/11
    研究報告書・技術報告書 フリー

    Highly efficient production of hydrogen without CO2 emission is achieved in the dehydrogenation of cyclic hydrocarbons under a non-steady spray pulse operation. Cyclohexane, methylcyclohexane, cis-decahydronaphthalene trans-decahydronaphthalene, cyclohexylbenzene, and bicyclohexyl were efficiently dehydrogenated by the Pt catalysts supported on active carbon. The rates of dehydrogenation were in the following order: cyclohexylbenzene > cyclohexane, methylcyclohexane, bicyclohexyl > cis-decahydronaphthalene, 1-methyldecahydronaphthalene > trans-decahydronaphthalene. Comparing the reactants, the highest reaction rate was observed for cyclohexylbenzene. Additionally, both in the lower temperature region (220 – 280°C) and the higher temperature region (280 – 400°C), the lowest activation energy was observed for cyclohexylbenzene (Activation energy was 63 and 29 kJ mol-1 for 220 – 280°C and 280 – 400°C, respectively). The highest hydrogen production rate was observed for bicyclohexyl, due to its high hydrogen contents in a molecule. Comparing the cis-decalin and trans-decalin, cis- isomer showed higher reaction rate than trans- isomer, reflecting the difference of free energy (ΔG) between the product (naphthalene) and the reactants.

  • 仮屋 伸子, 福岡 淳, 市川 勝
    2005 年30 巻2 号 p. 91-94
    発行日: 2005年
    公開日: 2022/04/11
    研究報告書・技術報告書 フリー

    The direct methanol fuel cell systems have already proved to be feasible for portable applications. However, there are still some drawbacks in the direct methanol fuel cells such as low electrocatalytic activity of the anodes, CO poisoning on Pt-based anode catalysts, and permeation of methanol through the PEM. To overcome these problems, we applied cyclic hydrocarbons (such as cyclohexane, methylcyclohexane, and tetralin) and secondary alcohols (such as 2-propanol and 2-butanol) to the direct PEM fuel cell (D-PEMFC) system. The dehydrogenation and hydrogenation of cyclic hydrocarbons is reversible and the fuels are regenerative and recyclable, thus the ‘rechargeable’ D-PEMFC is available by combination with electrolysis of H2O and electrochemical hydrogenation of hydrocarbons. Based on this background, we applied cyclic hydrocarbons and secondary alcohols to D-PEMFC, and observed the polarization curves of the electro-oxidation of cyclic hydrocarbons. High performance of the PEM fuel cell was achieved by using 2-propanol and 2-butanol as fuels with zero- CO2 emission and lower-crossover through PEM than with a methanol-based fuel cell. The performance of cyclohexanewas lower than those of alcohols, but the crossover of cyclohexane was significantly small, presumably due to the hydrophobicity of cyclohexane. The electro-reduction of acetone and water electrolysis mediated by the PEM was carried out at 80°C. Using Pt/C, PtRu/C and Pt black catalysts, 1–3% of conversions of acetone were observed.

  • 平井 嵩之, 桜井 誠, 亀山 秀雄
    2005 年30 巻2 号 p. 95-100
    発行日: 2005年
    公開日: 2022/04/11
    研究報告書・技術報告書 フリー

    Simulation study was conducted for a catalytic reaction using a high temperature heat exchanging type reactor with the heat-resistant anodized aluminum catalyst. SO3 decomposition reaction in the Iodine-Sulfur thermochemical hydrogen production process was adopted as a model reaction. Effect of catalyst shape on the heat exchanging performance was estimated. The shape of a catalyst was good in heat exchanging performance by order of a serrated fin type, a fin type, a plate type and a packed bed type reactor. In comparison with the packed bed type reactor, the reactor volume of serrated fin type reactor to be necessary for the decomposition reaction decreased to 35%. In addition, the exergy losses caused by a heat exchanging operation decreased to 64.2%.

解説
  • 神谷 信行
    2005 年30 巻2 号 p. 101-106
    発行日: 2005年
    公開日: 2022/04/11
    研究報告書・技術報告書 フリー

    Dimethylether (DME) is the smallest one in the ether’s group compounds. Beinggaseous under the atmospheric condition, DME is easily liquefied under the mild compressed condition such as at 6 atm. DME is harmless for human beings and therefore it is widely used as as praying media. DME is prepared by mainly two ways, i.e., direct and indirect methods. The former is synthesized from coal gas mixture and the latter is made by dehydration of methanol synthesized from coal gas mixture. Another epock making way of preparation of DME comes from C02 and H2.

    DMEi s used in many fields,a mong which application to diesel fuel for trucks and cars and also for direct DME fuel cells are extremely important in the future. Since DME has much advantages,it would be the 21st century’s clean energy.

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