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Volume 65, Issue 5
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[in Japanese]1986 Volume 65 Issue 5 Pages 301
Published: May 20, 1986
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSDownload PDF (231K) -
A New Concept for Evaluation of Coal QualityYoshiaki MIURA1986 Volume 65 Issue 5 Pages 302-314
Published: May 20, 1986
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSDegree of coalification and petrographic component have long been considered as the genetic properties governing the processing of coal. However, another genetic property, or degree of reduction, has come into use in USSR in fundamental and applied researches. Because of its potential importance in utilization of coal including coke making, a review of the Soviet studies is made with emphasis on the genetic meaning of the degree of reduction, the relation between degree of reduction and chemical structure of coal, the parameters to describe the degree of reduction and examples of applications of the degree of reduction.View full abstractDownload PDF (1882K) -
Satoshi OHSHIMA, Kikuko HAYAMIZU, Motoo YUMURA, Yasunori KURIKI, Morio ...1986 Volume 65 Issue 5 Pages 315-321
Published: May 20, 1986
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSA coal-liquefaction reaction was analysed by using the characterization chart and the following results were obtained.
1) A relationship between the aromaticity, fa, and the corrected atomic H/C ratio, (H/C) c, for coal-derived products agrees with that for various coals themselves. This fact suggests that the skelton structure of carbon-hydrogen for coal-derived products would be similar to these for coals. Hence it can be said that the deoxygenation reaction is one of important processes during the coal-liquefaction.
2) It is shown that a coal consists of components whose reactivities change continuously and the thermal cracking to radicals takes place from the components with higher reactivity. The radicals are stabilized by hydrogen offered from a donor-solvent to produce preasphaltenes, asphaltenes and oils. Because of the unreacted-coal, the preasphaltenes and the asphaltenes are consecutively converted to give oils finally, oil yield increases with the increase of reaction time.
On the other hand, the components with low reactivity remain in the unreacted coal, preasphaltenes and asphaltenes, and some of them do not produce radicals, even if the reaction conditions become more severe. The amount of these components is considered as unconvertible, and it is possible to make a rate equation where the coal liquefaction is correlated with the first-order irreversible reaction including the fractional ratio of unconvertibles.View full abstractDownload PDF (834K) -
Takayoshi SHINDO, Yozo OHOSHIMA, Hiroshi OHONUMA, Muneyoshi YAMADA, Ak ...1986 Volume 65 Issue 5 Pages 322-328
Published: May 20, 1986
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSReaction between hydrogen atoms and solvent treated coal specimens has been studied.
Domestic subbituminous coal, Taiheiyo, was first treated with 1: 1 mixture composed of carbon disulfide and pyridine at room temperature. The residual coal was heated at 200°C or 400°C in a stream of helium. The coal specimens so prepared were then subjected to the reaction with hydrogen atoms at 200°C and under 133Pa, using a conventional hydrogen discharge flow apparatus.
The reactivity of coal decreased by the solvent extraction. Specific gravity, refractive index, 1H-nmr spectra, and distillation behavior revealed, all in a consistent manner, that coal liquids obtained in the present study comprised mainly cycloalkanes of carbon numbers ranging from 6 to 22. They were, however, rich in higher boiling fractions, in comparison with those obtained by similar reaction with raw coal.
The average structure of the coal extracts was estimated to be tri- and/or tetrabutyl-benzene, while condensed ring aromatics was grown in the residual coal upon its heat treatment. The structural change in the coal specimens was well reflected on the properties of the coal liquids.View full abstractDownload PDF (976K) -
Hydrogenated Anthracene Oil SolventYoshinari INUKAI, Yoshio ADACHI, Masao HIBATA, Seiji ARITA1986 Volume 65 Issue 5 Pages 329-334
Published: May 20, 1986
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSSolvolysis liquefaction of subbituminous coal by short contact time at high temperature has been carried out using hydrogenated anthracene oil (H-A0) as a model solvent concerning the property and liquefaction ability of the solvent in the development of the solvolysis liquefaction phase II process.
The anthracene oil (AO) hydrogenated by sulfided Ni-Mo/Al2O3 catalyst was an excellent solvent for coal liquefaction in comparison with AO done by non-sulfided catalyst and original AO, and yielded the benzene- and quinoline-soluble fractions of coal in about 70% and 90%, respectively, by solvolysis liquefaction at 450°C for 10 min. Strongly hydrogenated AO was superior to weakly hydrogenated AO for the benzene-solublization of coal, but the quinoline-solublization of coal did not depend upon the degree of hydrogenation of AO. The hydroaromatics contained in H-AO were presumed to be hydrogen-donor species to coal; for they were converted to the corresponding aromatics in the analyses of the solvolysis liquefaction products.
The solvolysis liquefaction with various distillate fractions of H-AO suggested that the liquefaction abilities of hydroaromatics increased in the order of di-, tri-, and tetracyclic hydroaromatics; it showed that the higher-boiling fraction of H-AO with higher aromaticity was effective for the quinoline-solublization of coal.View full abstractDownload PDF (766K) -
Results of continuous gasificationMakoto KURAMOTO, Daizo KUNII, Takehiko FURUSAWA1986 Volume 65 Issue 5 Pages 335-340
Published: May 20, 1986
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSGasification of sawdust was conducted using a circulation system of heat carrier particles, which produced syngas of medium calorific value without using oxygen. The interior of the gasifier used in this experiment, which was made of SUS-316 (a main body of 155 mm in inner diameter and 1.25 m in tube height), was divided into four sections by intersecting two flat vertical plates at right angles. Two sections were used for the upflowing bubbling fluidized beds and the other two sections were used for the incipiently fluidized downcomers. The gasification of sawdust was carried out during fifteen hours without any troubles and the reverse motion of heat carrier particles. The obtained results demonstrated the potential advantages of this gasifier. The gas produced by both pyrolysis and steam gasification of sawdust, which were conducted at approximately 1200 K, was composed of mainly hydrogen, carbonmonoxide, carbondioxide and methane. The total yield of the produced gas of which the higher heating value was 13 MJ/Nm3 on the nitrogen-free basis was approximately 1.0Nm3/kg-dry sawdust on the nitrogen-free basis.View full abstractDownload PDF (841K) -
Study on Methanol Coal Mixture (II)Keizo OGINO, Masahiko ABE, Shinichi KAWANO, Hidemasa HONDA1986 Volume 65 Issue 5 Pages 341-347
Published: May 20, 1986
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSWettabilities of five kinds of original coals and of coals extracted with methanol have been studied in terms of a critical wetting concentration and a heat of wet-ting.
The critical wetting concentration of original coal in methanol/water mixtures, which is obtained from wetting rates, decreased with increase in the carbon content. The heats of wetting for original coals in methanol and/or in water decreased as carbon content in-creased up to C85.2% (Miike), and beyond the point it remained constant. The changes of the heats of wetting with volume ratio of methanol/water mixtures were dependent on various ranks of original coal.
From these results, it was found that the wettabilities of original coals in methanol, water, and methanol/water mixtures were influenced by surface-chemical structures of coals, especially, by surface acidic functional groups of coals. Moreover, surface-chemical structures for low ranks of coals were found to be different between the original coals and the coals extracted with methanol.View full abstractDownload PDF (1059K) -
Koji ANDO, Makoto AKIYOSHI, Toshio YAHATA, Takashi FUKUDA1986 Volume 65 Issue 5 Pages 348-354
Published: May 20, 1986
Released on J-STAGE: February 23, 2011
JOURNAL FREE ACCESSDiminution rate of hydrogen cyanide in a quarts tube heated by an electric furnace was investigated as a basic research for treating the dilute hydrogen cyanide which was liberated from cyanide-containing wastewater by means of air.
The experiments were carried out at the concentration of hydrogen cyanide 150 and 300 ppm and that of oxygen 1 and 21%, and at the temperature from 650 to 850°. The results obtained were as follows;
Data were corrected, taking gas mixing effect into consideration. Diminution rate of hydrogen cyanide was proportional to that concentration and the effect of oxygen level was not distinguish. The observed rate constant obeyed Arrhenius law, and activation energy and frequency factor obtained were 36.2kcal/mol and 1.1×107 sec-1, respectively.View full abstractDownload PDF (937K) -
[in Japanese]1986 Volume 65 Issue 5 Pages 355-363
Published: May 20, 1986
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSDownload PDF (2661K)
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