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Volume 64, Issue 3
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[in Japanese]1985 Volume 64 Issue 3 Pages 155
Published: March 20, 1985
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSDownload PDF (259K) -
Naoshi OTOTAKE1985 Volume 64 Issue 3 Pages 156-165
Published: March 20, 1985
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSAlthough a highly loaded coal water slurry has internationally become a center of attraction in connection with the liquefaction of coal, its practical preparation should encounter technical difficulties to simultaneously satisfy the requirements of the industrial use as follows.
(1) it should contain more than 70% by weight of coal on a moisture free basis, (2) lower apparent viscosity than the order from 1000 to 2000 (cP) is necessary, (3) it could be stored up to 40-50 days without significant sedimentation or particle separation.
To cope with those situations, it is considered to be very important to investigate the effects of coal source, of coal concentration and its particle size and size distribution and also of the acts of additive on the rheology of concentrated slurries.
Those kinds of discussion are often so inclined to be qualitative that this paper is provided as far as possible to introduce quantitative results such as the influences of particle size and its distribution on packing density also on the both of apparent viscosity and yielding stress, and the theoretical or empirical flow properties, respectively. In the last section, a brief introduction is given for the additive and its char-acterization functions.View full abstractDownload PDF (1273K) -
Kiyoshi SAITO, Mizuo TANAKA1985 Volume 64 Issue 3 Pages 166-173
Published: March 20, 1985
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSThe low rank coal, especially brown coal, has large contents of moisture and volatile matter, so, if the volatile matter of such a coal is analyzed by JIS method, its analytical value has a tendency to give a too high value because of flashing and partial combustion of sample.
This study has been carried out to establish the analytical method of volatile matter of brown coal and lignite which is based on the loss in mass, less that due to moisture, when the sample is heated out of contact with air under standardized conditions.
Experimental results show that it is essential for avoiding the sparking effect and the partial burning of sample to take 0.5g of the sample and to heat the sample by two stage system and to pass inert gas into the muffle furnace in the overall duration of the measurement.
Improved method provides reliable analitical values. The repeatability is good and the coefficient of variation is 0.5%.View full abstractDownload PDF (1258K) -
Molecular-Ion-Spectrum MethodYoshio NIWA, Keiichiro ISHIKAWA, Yazaemon MORITA, Yoshikazu SUGIMOTO1985 Volume 64 Issue 3 Pages 174-183
Published: March 20, 1985
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSA characterization method of coal derived oils has been studied by FI mass spectrometry in combination with high resolution mass spectrometry and the molecular-ion-spectrum method is proposed. The method involves the calculation of a molecular ion spectrum by eliminating isotopic ions from an observed FI mass spectrum, the assignment of an elemental composition to each molecular ion and the classification of components based on their skeletal structures. Several examples of the application reveal usefulness of the method for the characterization of coal derived oils and the analysis of chemical reactions in which coal derived oils are involved.View full abstractDownload PDF (1365K) -
Isao MOCHIDA, Kinya SAKANISHI, Taiji OISHI, Yozo KORAI, Hiroshi FUJITS ...1985 Volume 64 Issue 3 Pages 184-192
Published: March 20, 1985
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSThe catalytic hydrodenitrogenation (HDN) reactivities of coal liq-uid fractions (kerosene, light and heavy oils) were examined at 400°C under hydrogen pressure (-200atm) using a commercial nickel-molybdenum catalyst (Sphericat. 502).
Nitrogens of the kerosene and the light oil were easily removed under the present conditions to be almost nil, whereas that of heavy oil was hardly removed, the denitrogenation level being as low as 30% after the reaction.
The structural analyses of coal liquids indicated that nitrogens were present in mono-and hi-cyclic aromatics in the kerosene and the light oil, whereas in tricyclic or larger aromatics in the heavy oil. Such structural differences may result in the different reactivities above described.
The heavy oil was further divided into acidic, basic and neutral fractions to study their respective reactivities. According to the nitrogen balances, the acidic fraction was most reactive, although hydrodehydroxylation may convert some of the fraction into basic and neutral fractions. The hydrotreatment decreased very much the formation of insoluble matter during the extraction to increase the neutral fraction, indicating that the fraction contains the edge-pyrrole structures to be easily removed. The basic fraction was most unreactive.
The structural analyses of the hydrotreated heavy oil suggest that insufficient hydrogenation of the aromatic rings including the heterocyclic part under the present conditions is a reason for the low reactivity of heavy oil.
Based on these results, the hydrodenitrogenation mechanism of coal liquid fractions was discussed to propose a more efficient reaction design.View full abstractDownload PDF (1163K) -
Yozo KORAI, Katsuhiro NAGAYAMA, Takaaki SHIMOHARA, Isao MOCHIDA, Toshi ...1985 Volume 64 Issue 3 Pages 193-201
Published: March 20, 1985
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSThe formed coke making of Hunter Valley (slightly fusible) coal copreheattreated Hunter Valley has been studied using petroleum pitch A 240 as a coking additive to reveal the effects of copreheattreatment and carbonization conditions on the strength and CO2 reactivity of the resultant formed coke by considering their mutual relation.
The copreheated coal prepared under rather milder conditions (around 450°C within 15 min) exhibited better fusibility at the carbonization stage, providing a solid formed coke of high strength when carbonized in a vessel without moulding pressure at a low heating rate. In contrast, higher forming pressure and higher heating rate resulted in a expanded coke of low strength. The copreheattreated coals prepared under severe conditions (at higher temperature than 480°C for longer soaking time than 8.0min) did not fuse well when carbonized at a lower heating rate without forming pressure, resulting in the low strength. These severely copreheattreated coals required to get high strength formed coke higher pressure of around 200kg/cm2 and smaller particle size less than 100 mesh before forming. A high heating rate at the carbon-ization was also favorable for the high strength.
Such results suggest that the amount of volatile matter, its released rate at the carbonization stage and the size of pore remained after the forming affect the fusibility and adhesion extent of copreheattreated coal particles in the carbonization stage.
Fine grained mosaic anisotropy was developed in the whole cokes thus produced, of which CO2 reactivities at 1000°C was low and comparable to that of a commercial blast furnace coke. The HI or BI fraction of a copreheated coal produced cokes of very high strength (>300kg/cm2), however, their reactivities were very high. Many micropores (<1μm) observed by SEM in the cokes may enhance the reactivity althongh they are indifferent to their strength at this low strength level. The effects of copreheat-treatment and carbonization conditions on the coke quality were mecha-nistically discussed by relating them mutually.View full abstractDownload PDF (1694K) -
Rikio YAGINUMA, Tsuneo YOSHII1985 Volume 64 Issue 3 Pages 202-209
Published: March 20, 1985
Released on J-STAGE: February 23, 2011
JOURNAL FREE ACCESSLiquefaction experiments were carried out Taiheiyo coal using ten kinds of metal hydroxides such as Cu (OH) 2, Cd (OH) 2, Co (OH) 2, Ni (OH) 2, FeO (OH), Zn (OH) 2, Cr (OH) 3, Sr (OH) 2, Mg (OH) 2, Al (OH) 3. The results can be expressed as follows;
1) Cu (OH) 2, Cd (OH) 2 and Co (OH) 2 are highly active catalysts possesing high oil-selectivity.
2) FeO (OH) and Ni (OH) 2 are moderatly active catalysts possesing oil-selectivity.
3) Zn (OH) 2, Cr (OH) 3, and Sr (OH) 2 are lowly active catalysts possesing lower oil-selectivity than red mud+sulpher catalyst.
4) Al (OH) 3, Mg (OH) 2 are inactive catalysts.
5) Jarosite and Malachite are highly active catalysts.
6) Appearance of catalytic activeity of Cu (OH) 2 is likely to give in the process of reducing.View full abstractDownload PDF (1175K) -
Masashi IINO, Jun KUMAGAI, Osamu ITO1985 Volume 64 Issue 3 Pages 210-212
Published: March 20, 1985
Released on J-STAGE: February 23, 2011
JOURNAL FREE ACCESSExtractions of Shin-yubari, Miike, and Zao Zhuang (China) coals with carbon disulfide-N-methyl-2-pyrrolidone mixture at room temperature for 30min gave high yields (daf) of 55%, 37%, and 60%, respectively. The effects of extraction time, coal/solvent ratio, and particle size of the coal were studied for Shin-yubari coal. The yields for the extractions more than 15min are almost the same (≅55%) The increase of coal/solvent ratios from 2g/100ml to 8g/100ml and the increase of particle sizes from -170 mesh to -16 mesh gave little change to the extraction yields. H/C ratio of the residue from the extraction (53% yield) of Shin-yubari coal was found to be 0.82, compared to 0.87 of the raw coal.View full abstractDownload PDF (397K) -
Akihiro NAKA, Hiroshi SUGIYAMA, Shuichi HONJO, Tomoo SUGIYAMA1985 Volume 64 Issue 3 Pages 213-217
Published: March 20, 1985
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSFor highly loaded coal-water slurry (CWS), the authors first eval-uatedthe effect of nonionic surface active agents on highly loaded CWS. Two kinds of bituminous coals different in carbonization degree, such as Tatung coal and Blair Athol coal, were subjected to examination to obtain the following results:
1) With Tatung coal more carbonized, CWS of high concentration can more easily be produced than with Blair Athol coal.
2) Adducts of alkylphenol, aliphatic alcohol or fatty acid, with ethylene oxide (hereinafter simply called EO), exhibited almost no effect on highly loaded CWS.And besides those with a small number of moles of EO added had effect on reducing the concentration of CWS.
3) A block copolymer obtained by adding EO equivalent to a molecular weight of 6, 400 to both ends of polypropylene glycol with a molecular weight of 3, 200 had a good effect on highly loaded CWS.
Second, the above alkylene oxide copolymers and sodium salt of formalin conden-sate of naphthalenesulfonic acid and sodium salt lignosulfonate were compared for effect on highly loaded CWS. As a result, alkylene oxide copolymers were found to be muchbetter in such effect.View full abstractDownload PDF (587K)
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