Journal of the Japan Institute of Energy
Online ISSN : 1882-6121
Print ISSN : 0916-8753
ISSN-L : 0916-8753
Volume 78 , Issue 5
Showing 1-4 articles out of 4 articles from the selected issue
  • Measured Cruising Range under Practical Conditions
    1999 Volume 78 Issue 5 Pages 315-324
    Published: May 20, 1999
    Released: June 28, 2010
    The data of cruising range of electric vehicle are strongly required under the practical conditions. In this paper the effect of the air temperature around a vehicle, the friction coefficient of the test road, the connective ways of batteries, the natural recovery of the voltage of batteries after the vehicle stops by shortage of storage energy in them and number of slopes included in the test road on the cruising range between charges of electric motorcycle are revealed empirically. It is also confirmed that the potential of the cruising range of the tested electric motorcycle is enough to be applied for the newspaper delivery.
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  • Kazushige NAGASHIMA, Yoshitaka YAMAMOTO, Takeshi KOMAI, Hiroaki HOSHIN ...
    1999 Volume 78 Issue 5 Pages 325-331
    Published: May 20, 1999
    Released: June 28, 2010
    The directional growth experiments of tetrahydrofuran (THF) clathrate hydrate were carried out from the solution. The diffusion processes of solutes (THF and salt) in the solution were observed near the growth interface using a Mach-Zehnder interferometer. During the growth of hydrate from off-stoichiometric solution, the transport of guest molecules (THF), caused by the concentration difference between the solid and liquid, was clearly observed near the interface. During the growth from THF-17H2O solution, the THF concentration was uniform in the solution even near the interface . The composition was found to be stoichiometric for hydrate formation. The effect of salt as the inhibition of hydrate formation was investigated using the stoichiometric solution with the addition of 3 wt% sodium chloride. Analyzing the interference fringes, the salt concentration distribution was obtained around the growing hydrate. The salt concentration increased with time due to the rejection of salt at the growth interface and decreased sharply with the distance from the interface into the bulk concentration. Theses results lead to the conclusion that the freezing temperature of hydrate is considerably reduced by the local increase of salt concentration. Finally, it should be emphasized that the present method is very useful for the research of fundamental process for hydrate formation, i. e. mass transport process in the solution.
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  • with a 50 ton (dry coal) /day Pilot Plant
    Osamu OKUMA, Shunichi YANAI, Motoharu YASUMURO, Eiichiro MAKINO
    1999 Volume 78 Issue 5 Pages 332-344
    Published: May 20, 1999
    Released: February 23, 2011
    The wall scales and reactor sediments formed during the liquefaction of Victorian brown coal with a 50 ton (dry coal) / day pilot plant were analyzed to clarify the mechanisms of their formation and the relationship between their amount and the operation time of the pilot plant, because they are very troublesome for long-term operation of a coal liquefaction plant.
    The scales on the preheater and the connecting pipe between the preheater and the first reactor consisted of NaCl (50-60 wt%) and Fe1-xS (30-40 wt%) originating from the used catalyst (Fe2O3 and S) and coal. The wall scales on the reactors mainly consisted of carbonates of Ca, Mg and Na which originated from ion exchangeable cations in the coal.Their main components were CaCO3, CaMg (CO3) 2 and Na6Mg2 Cl2 (CO3) 4 and changed in order from the first reactor to the fourth reactor. All scales were confirmed to be hard inorganic materials which had a layered structure.
    The total amount of the scale formed during the operation of the pilot plant was correlated with IEC / Ash (CLB) ×COT ((kg/kg) ·Eh), where ICE and Ash (CLB) were the amount of the ion exchangeable cations (Ca, Mg and Na) in the coal and catalyst, and that of the ash in the heavy liquid product (coal liquid bottom, CLB) used as a part of the solvent, respectively. This result suggested that unreactive solid particles (ash) in the feed slurry suppressed the scale formation during the liquefaction. In addition, an increase in pressure drop observed during the operation was also found to be mainly caused by the preheater scale.
    The sediments of the particles found in the reactor bottom were spheres of 0.5-1.0 mm and consisted of similar components to those of the wall scales. Their accumulation was prevented by withdrawing a small amount of the slurry from the first reactor bottom.
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  • Jun WADA, Toshio TSUJINO
    1999 Volume 78 Issue 5 Pages 345-353
    Published: May 20, 1999
    Released: June 28, 2010
    Pilot testing of a new wet desulfurization process using dimethyl propylene urea, a polar heterocyclic aprotic solvent, with COS hydrolysis catalyst has been carried out using a high sulfur coal based syngas. This process, named Polar-1TM has demonstrated the superior performance for IGCC economics, such as simultaneous absorption of organic and inorganic sulfur compounds and high selectivity of sulfur compound absorption over CO2 absorption. The investigation of testing data has also been extended to acid gas specification, solvent degradation and effect of trace components in syngas.
    A comparative modified MDEA solvent has also been tested in the same pilot plant, and Polar-1TM process has demonstrated the superiority over modified MDEA process in the principal process performance for IGCC economics. This innovative desulfurization process, “Polar-1TM” is suggestive to overwhelm the existing wet desulfurization processes by deleting upstream gaseous COS converter and making compact design of sulfur recovery plant, for coal based IGCC application in terms of the overall investment and utilities consumptions.
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