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Volume 57, Issue 9
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Koji OUCHI, Tomei TAKEGAWA, Kazuo MAKINO1978 Volume 57 Issue 9 Pages 713-717
Published: September 20, 1978
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSHigh pressure DTA of flow type was applied to the studies on the hydrogenation reaction of coals at the constant temperature. They showed the characteristic exothermic heat evolution in 15 minutes. The area of this exothermic curves is proportional to the amount of water produced in the same duration and to the amount of benzene soluble part of the products. These results suggest that the exothermic heat evolution results from the dehydration by hydrogenation reac-tion, accompanying with the splitting of ether linkages which leads to the increase of benzene soluble part.View full abstractDownload PDF (588K) -
Kazuo MAKINO, Noboru ORIHARA, Koji OUCHI1978 Volume 57 Issue 9 Pages 718-720
Published: September 20, 1978
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSThe hydrogenolysis reaction of Taiheiyo coal was carried out using metallic tin as catalyst. The effect of reaction temperature, pressure and the ratio of catalyst-coal was examined. The conversion increased with the increase of temperature, pressure or ratio of catalystcoal and the conversion of 42%-74% and liquefaction percent (low boiling liquid plus benzene soluble part) of 20%-50% were obtained.View full abstractDownload PDF (311K) -
Coal-Tar Pitch and Suspensions of Coal ParticlesKazuteru OSAFUNE, Tsuyoshi SAKAKI, Seiji ARITA, Hitoo KAKIYAMA, Hidema ...1978 Volume 57 Issue 9 Pages 721-728
Published: September 20, 1978
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSMeasurments of viscosities and flow properties for asphalt, coal-tar pitch and coal suspensions have been performed in the tempreture range from 160° to 420°C using concentric cylinder viscometer.
The viscosity of asphalt (Khafji vacuum residue) decreased with increasing tempreture, and the dependence of viscosity on the tempreture below 360°C was descrived by the Andrade's viscosity equation (η=η exp (E/RT)). The flow activation energy for Khafji asphalt was 12.13 kcal/mol below 240°C, while for coal-tar pitch was 20.15 kcal/mol below 200°C. The difference in the activation energies was interpreted in terms of the difference of the molecular structure between two bitumens. An unusual flow behavier for the suspension of Miike coal (C: 82.6%) in asphalt pitch (heat-treated asphalt) has been observed, and it was discussed in terms of swelling and dissolving of coal particles into asphalt pitch. For the suspensions of Miike coal in asphalt ranging in concentration from 0. 0 to 35.5 wt. %, flow curves at about 210°C were prepared, and they showed Newtonian flow under the shear rate range from 3.33 to 415.9 sec-1. Furthermore, the relative viscosity was plotted against volume fraction of coal, and Robinson's formula (ηγ=1+kφ/ (1-Sφ)) was found most applicable to any concentration of suspensions for the tempreture range from 200° to 300°C.View full abstractDownload PDF (999K) -
Isao MOCHIDA, Akira TAKARABE, Kenjiro TAKESHITA1978 Volume 57 Issue 9 Pages 729-739
Published: September 20, 1978
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSSolvolytic liquefaction of coals of some range was studied with a variety of solvents at 370-390°C under nitrogen atmosphere in order to elucidate roles of the solvent in coal liquefaction of this kind and to find a proper solvent for the better yield of liquefaction. The yield was found to depend strongly upon the natures of the coal as well as the solvent under the present conditions. Pyrene and a SRC-BS pitch were excellent solvents for Oyubari coal, which was fusible in high fluidity at the liquefaction temperatures. However, the former was very poor for Itmann and Taiheiyo coals which were fusible at higher temperature or non-fusible, respectively. The mechanism of solvolytic liquefaction was discussed, taking account of natures of the coal at the liquefaction temperature to understand the properties of the solvent required for the high yield against non-fusible coals in the solvolytic liquefaction.
It is revealed that the solvolytic reaction should take place between the solvent and the coal when the non-fusible coal is expected to be liquefied at high yield. The hydrogen transfer from SRC-BS to the coal is assumed to be responsible for the high liquefaction yield for such a coal.View full abstractDownload PDF (1311K) -
Kiyotaka SAKAI, Toyoki SUGITA1978 Volume 57 Issue 9 Pages 740-747
Published: September 20, 1978
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSThe submerged combustion is one of the method for heating and/or evaporation, and it is said to be very useful for heating because it has high thermal efficiency reached to around 90-95%. If it is used as a heating apparatus, heat loss by the steam vaporized from the water bath must be taken into consideration to increase the total efficiency of this system. In this paper, a doublepipe type heat exchanger was used to recover the heat of exhausted steam. Some design methods of the cooler condenser presented so far were applied to this case, which contained a lot of inert gases such as N2, CO2 etc. and its availability was investigated.View full abstractDownload PDF (843K) -
Susumu YOKOYAMA, Naohide TUZUKI, Takashi KATOH, Yuzo SANADA, David M. ...1978 Volume 57 Issue 9 Pages 748-757
Published: September 20, 1978
Released on J-STAGE: February 23, 2011
JOURNAL FREE ACCESSHeavy oil derived from hydrogenolysis of Hiawatha, Utah, coal was separated by dual packed silica alumina liquid chromatography in accordance with the respective hydrocarbon types and each compound type was fractionated by gel permeation chromatography by the magnitude of their molecular size. It may be assumed that the molecular ion sensitivity coefficient for low-voltage mass analyses are not so largely different among components constituting the respective LC-GPC subfractions inasmuch as the structure of compound types and carbon numbers of alip hatic substitution are limited. Therefore, the structural analyses of GPC subfrac-tions from Fr-D-1 to Fr-D-7 of diaromatic compound were investigated by gas chromatography-mass spectrometry of a low resolution and low energy voltage (10eV) method, and by direct injection for higher molecular weight GPC subfractions eluted earlier. Mass spectra were measured with the integrating multiscan technique. Integrated mass spectra of molecular ion calculated by a computer were dealt with to esimate the hydrocarbon type and carbon numbers of alkyl groups substituted on the basis of Z values which indicates the deficiency of hydrogen in the compounds.
From these results, it was shown that Fr-D-2 to Fr-D-7 consist mainly of homologous naphthalene derivatives with less amounts of mono-and triaromatic ring series. With regard to the respective type of naphthalen derivatives constituting each LC-GPC subfraction, the carbon number of alkyl substitution was found to decrease gradually with the increasing GPC fraction numbers from Fr-D-2 to Fr-D-7. For carbon numbers of alkyl substitution of the respective types of naphthalene de-rivatives, alkylnaphthalene series were found to have a range of 0 to 21, 0 to 18 for mononaphthenonaphthalene, 0 to 13 for dinaphthenonaphthalene, 0 to 8 for trinaphthenonaphthalene, respectively.View full abstractDownload PDF (1116K) -
Tugitoshi OGURA, Michio WATANABE, Akio HIRAKI1978 Volume 57 Issue 9 Pages 758-764
Published: September 20, 1978
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSThe authors conducted NO emission test by burning several kinds of oil fuel in a test furnace and compared on the basis of their kinds and components, the NO emission characteristics thereby obtained.
For the purpose of extracting oil-fuel components, the authors broke down oil fuels by solvent extraction with n-hexane and benzen, in accordance with the One's rapid method. The test results indicate that the NO production greatly various with oil-fuel components, which can be indicated as follows.
Light oil≤Top from vacuum distillate<Maltene from residual oil<Maltene from vacuum residual oil<Asphaltene from vacuum residual oil>β-resin
The authors therefore concluded that the heavier the oil fuel burned, the greater the amount of NO produced, and that the amount of NO emission could be predicted based on the solvent extraction data.View full abstractDownload PDF (843K) -
KineticsMikio MORITA, Kunio HIROSAWA, Koji OUCHI1978 Volume 57 Issue 9 Pages 765-773
Published: September 20, 1978
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSBy use of a 300ml high pressure batch autoclave, in the presence of a massive quantity of zinc chloride hydrocracking of akabira coal and akabira coal extract was carried out at the reaction temperature from 300°C to 425°C under the hydrogen pressure of about 190kg/cm2. The changes of the conversion and of the properties of the reaction products were investigated with the reaction time and the reaction rate was analyzed. The conversion increased with the reaction time and temperature but had a tendency to decrease at higher temperature. The gaseous product increased in the yield and changed into methane, ethane and propane-rich component gas with the reaction time and temperature. By the measurements of the gel permeation chromatography, the liquid product was found to consist of three compound groups whose weight-avarage molecular weight were about 120, 250 and 800 to be ultimately hydrocracked into the 120 molecular weight compound group by a way of a parallel and consecutive mixed reaction. Taking account of the changeable properties of reactants and products, i. e. these changeable reactivities, kinetics was considered. Assuming that instantaneous reaction rate was linearly proportional to the quantity of unreacted coal or extract (benzene-insolubles), the overall rate constants at an arbitrary conversion satisfied the Arrhenius equation. The activation energy increased with the conversion and it could be shown that the overall hydrocracking reaction was changing into the difficult with the progress of the reaction.View full abstractDownload PDF (999K) -
Hydrogasification at Elevated PressuresYoshiyuki NISHIYAMA, Noriyasu SETO, Yasukatsu TAMAI1978 Volume 57 Issue 9 Pages 774-780
Published: September 20, 1978
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSA Japanese bituminous coal, Mayachi coal, was treated with liquid ammonia four times at 120°C in an autoclave. Five per cent of nickel to coal (in weight) was impregnated from an aqueous solution of nickel nitrate, Gasification with hydrogen was conducted in a fixed-bed, flow type apparatus at 900°C for 4 hours at pressures from 5 to 30kg/cm2G.
Methane formation profiles had several peaks, among which last one observed after the temperature became 900°C was ascribed to the catalytic gasification of carbon to methane. Comparison of the amount of methane formed from untreated (U) and treated (T) specimens either with (C) or without (N) catalyst revealed that the effect of liquid ammonia treatment coupled with the catalytic action of nickel became less pronounced as the reaction pressure was raised. A simplified kinetic analysis showed that the rate of methane formation (M) at the later stage of the reactions was first order and 1.5th power with respect to hydrogen pressure for catalytic and non-catalytic reactions, respectively. An enhanced contribution of non-catalytic reactions and an interference of mass transfer by nickel seem to explain the diminuation of the effect of liquid ammonia treatment at higher prsssures.View full abstractDownload PDF (1180K) -
Yoneshiro TAZAKI, Junichi KAWABATA, Shigeo MITSUI1978 Volume 57 Issue 9 Pages 781-790
Published: September 20, 1978
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSThis paper describes a manufacturing method of active carbon from coal char by use of 2-and 3-stage fluidized bed technique.
One or two perforated plates having larger holes than the particle size partitioned the fluidized bed into two or three stages. Coal char particles were fed cocurrently with gas to the bottom stage and discharged from the top stage of the bed, where small and light particles were mostly transferred to the upper stage through the segregation phenomenon.
It was found that the Methylene blue adsorbability of the active carbon produced by 2-and 3-stage fluididized beds were about the same as those produced by the single stage fluidized bed with batchwise operation for the same residence time of char.
The use of 3-stage fluidized bed made possible larger through-put of coal char particles than the 2-stage fluidized bed.View full abstractDownload PDF (1190K)
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