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Volume 64, Issue 6
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[in Japanese]1985 Volume 64 Issue 6 Pages 363
Published: June 20, 1985
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSDownload PDF (234K) -
Mituho HIRATO1985 Volume 64 Issue 6 Pages 364-373
Published: June 20, 1985
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSIn case of scale-up for coal gasifiers, we must take into considerationnext four factors.
(1) reactivity and flow pattern
(2) operability and controllability
(3) manufacturing limit
(4) transport problem
But, as a matter of fact, the gasifiers are limited mostly by the fourth factor.Consequently the maximum outer diameter of gasifiers is about five meters, and innerdiameter is about four meters. Therefore, the maximum capacity of gasifiers is estimatedto be about 1200 t coal/day for the moving bed type, 3000 to 4000 t/d for thefluidized bed type, and 4000 to 5000 t/d for the entrained bed type.
For the design of large scale gasifiers, the author analyzed the scale-up methodson Lurgi moving bed, Westinghouse fluidized bed, Rheinbraun High TemperatureWinkler, and Texaco entrained bed.View full abstractDownload PDF (1458K) -
GC-MS Analysis of n-Hexane Soluble PortionsTsutomu KATO, Shiro USAMI, Kiyoshi HASEGAWA, Hiroyuki MIYAKE, Yutaka O ...1985 Volume 64 Issue 6 Pages 374-384
Published: June 20, 1985
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSCompound-type analyses (Z number) of n-hexane soluble portions (HS) of reductively methylated Yubari and Taiheiyo coals were studied by GC-MS.
These HS were separated into 6 fractions using GPC, which were subsequently fractionized into 4-11 subfractions with liquid chromatography (Fig. 1). The true Z numbers of each molecular ion peaks were decided by high resolution mass spectra and contents of the type compounds were determined by molecular ion strength of mass chromatograms.
Aliphatic hydrocarbons eluted in hexane fractions and di-, tri-, tetra-, penta- and hexacyclic aromatic hydrocarbons (Z=-16--32) in benzene-hexane fractions and oxygen-containing aromatic hydrocarbons (Z=-20--28) in methanol fractions.
The contents of the type compounds contained largely in both HS were remarkably different (Table 8). Paraffins and aromatic type compounds with Z=-20 and-22 were more abundant in Yubari HS, whereas the compounds Z=-18 was more abundant in Taiheiyo HS. Naphtalene dimers were found in both HS. Numbers of alkyl side chain range from 0 to 7 and have a maximum at 3 in Yubari HS and 2 in Taiheiyo HS (Table 8).View full abstractDownload PDF (1361K) -
Effect of Ratio of Coal Liquid to Petroleum Gas OilKoji UKEGAWA, Teruo KONDO, Akimitsu MATSUMURA, Katsuya KOGUCHI, Etsuro ...1985 Volume 64 Issue 6 Pages 385-392
Published: June 20, 1985
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSHydrotreating of the mixed oils of coal liquid and petroleum gas oil (gas oil) have been carried out to clarify the relationship between the properties of product oils and the ratio of coal liquid to gas oil. The coal liquid was the distillate produced from 1 ton/day solvent-coal liquefaction plant. The gas oil was commercial gas oil without additives. Ni-Mo-Al2O3 commercial catalyst (KF-840) was used as a hydrotreating catalyst. Four mixed oils were prepared as feedstocks; 10, 30, 50 and 100 vol % of coal liquid were mixed with 90, 70, 50 and 0 vol % of gas oil, respectively.
The smaller ratio of coal liquid to gas oil resulted in the higher per cent denitrogenation and the higher per cent hydrogenation of product oils.
The hydrotreating of model compound, quinoline, has been carried out as well. The lower concentration of quinoline gave the higher per cent denitrogenation of quinoline. The higher aromaticity of solvent gave the lower per cent denitrogenation of quinoline.View full abstractDownload PDF (845K) -
Tsuyoshi SAKAKI, Yoshinari INUKAI, Seiji ARITA1985 Volume 64 Issue 6 Pages 393-401
Published: June 20, 1985
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSSYNOPSIS: -The viscosity of coal-derived oil is one of the fundamental data for the design of coal liquefaction plant. In this paper, the prediction method of the viscosity of middle oil fractions from coal-derived oils was investigated.
SYNOPSIS: -The viscosity of coal-derived oil is one of the fundamental data for the design of coal liquefaction plant. In this paper, the prediction method of the viscosity of middle oil fractions from coal-derived oils was investigated.
Coal tar distillates and coal liquefaction products were distilled into a number of fractions with narrow boiling range. The viscosity of each fraction was measured in the temperature range from 40 to 100°C by using a rotating rheometer. The logarithms of the viscosity varied linearly with the logarithms of the temperature for middle oil fractions in the mean boiling point (50 vol% off temperature) range from 200 to 375°C. Each of the straight line converged to a specific point (245°C, 0.42mPa.s) and the gradient of the straight line depended on the mean boiling point of each fraction.
Using these results, the following equations were deduced for predicting the viscosity of the middle oil fractions from coal tar or coal liquefaction product at an arbitrary temperature.logη=2.389-log t/2.389-log t1 (0.3768+log η1)-0.3768 (1)
logη= (2.389-log t) 10n-0.3768n=0.00350b50-0.8451 (2)
The viscosity (mPa. s) at an arbitrary temperature t (°C) can be calculated from eq.(1) if the viscosity at a certain temperature t1 is known, or from eq.(2) if the 50 vol% off temperature tb50 (°C) of the fraction is known.
A nomogram for the same purpose was also constructed. The estimation of the viscosity can be made using tb50 of the fraction, and a more accurate value will be obtained if the viscosity at a certain temperature is known.View full abstractDownload PDF (1245K) -
Akira TOMITA, Yoshiyuki YUHKI, Kazutoshi HIGASHIYAMA, Takayuki TAKARAD ...1985 Volume 64 Issue 6 Pages 402-408
Published: June 20, 1985
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSNickel exhibits a very large catalytic activity in the steam gasification of low rank coals at around 773 K. In order to clarify the reason of this high activity, the surface area and pore size distribution were determined for chars obtained under various gasification conditions. CO2-surface area strongly depended on the gasification temperature, but was almost independent of the reaction time, conversion, catalyst or gasification velocity at that time. The rapid gasification stage terminated at a coal conversion around 85%, and the rate became very small. This rate decrease was not due to the drop of char surface area. Thus, it was concluded that both high gasification rate in the initial stage and rate decrease in the final stage are related to the activity of nickel catalyst itself.
The pore size distribution curve during the catalytic gasification showed the presence of transitional pores of around 10 nm in diameter which is very close to the size of catalyst. This seems to suggest that the reaction took place through the movement of catalyst which resulted in the formation of pit behind it.View full abstractDownload PDF (996K) -
Shohei TAKEDA, Kunihiro KITANO, Junichi KUBOTA, Junichi KAWABATA, Shun ...1985 Volume 64 Issue 6 Pages 409-418
Published: June 20, 1985
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSApparent rates of CO2 gasification of chars obtained from thirteen different kinds of coals were measured at temperatures of 1073-1273 K and under pressures of 0.3-1.6 MPa by means of a high pressure TGA apparatus. Changes of the surface area and the carbon structure of the reaction residue during gasification were also measured at various char conversions from 0 to 0.90.
The initial surface area of char obtained by carbonization prior to gasification was shown to depend not only on the coal nature and carbonization temperature but also on the heating rate.For all chars employed the apparent initial reaction rate increased in proportion to P0.25. During gasification the surface area of the reaction residue increased rapidly at the early stage of the reaction and then decreased after showing a maximum which was greater for lower temperatures.
The instantaneous rate based on the unit surface area also changed with the conversion. For all coal chars it decreased and leveled off at a conversion less than about 0.3. In a coversion range between 0.3 and 0.8 it was almost steady and decreased again towards completion of the reaction . Though the steady rate decreased with the rank of raw coal, the activation energies were approximately the same for all chars, being 190-210 KJ/mol.
The growth of (002) peak in the X-ray diffraction spectrum for some kinds of chars, which was specified as caused by graphite structure formed during reaction, corresponded well to the decrease of instantaneous rate at the final stage of the reaction. The formation of graphite structure in such a low temperature was inhibited by deashing the char before gasification.View full abstractDownload PDF (1413K) -
Hajime NAKAMURA, Akihiro MATSUURA, Takeshi MORITA, Masanori INUZUKA, Y ...1985 Volume 64 Issue 6 Pages 419-422
Published: June 20, 1985
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSIn order to obtain the fundamental data related to the heat transfer in acoal liquefaction process, the thermal conductivity of fractions in a recycle oil were measured at various temperature by using the transient hot wire method, where the fractions were prepared into 16 boiling fractions by centrifugal molecular still.
Then, the following results were obtained.
i) Thermal conductivity decreases as increasing temperature.
ii) The correlation between thermal conductivity and A.P.I. gravity as mentioned in Gray's work can not be observed clearly.
In addition, relationships among A.P.I. gravity, distilled temperature of fractions and average molecular weight were presented.View full abstractDownload PDF (465K)
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