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Volume 44, Issue 12
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[in Japanese]1965 Volume 44 Issue 12 Pages 773
Published: December 20, 1965
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSDownload PDF (198K) -
Hiroshi Okano, Atsuo Aihara1965 Volume 44 Issue 12 Pages 774-782
Published: December 20, 1965
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSA regional variation of coal quality was recognized within the course of writers' 1959-1960 prospecting work for hard coking Coal at Kianga-Moura area in the Great Syncline Coalfield (Bowen Basin), and some upper Bowen coals in the central part of the basin are delt with.
The higher rank (higher C content) coals are protted on the part of lower values in a coal band of the H/C versus O/Cdiagram (Fig. 4), reproduced from analitical data of localities (tab. 1). Distances between coal localities and western limit line of the “Dawson Tectonic Zone, ” a striking folding and faulting zone in the south eastern portion of the basin, connecting Banana and Bluff via Baralaba, in which a close connection of the tectonic zone and regional rank variation is recognized, viz. the nearer the zone, the higher the rank. From a geological view point of minor distribution of igneous rock in the central part of the basin with local exception in the vicinity of Collinsville, igneous effect to the rank variation is negligible in general. The thickness of overburden (depth of burial) that has important concern to the rank variation is assumed geologically to be limited at the base of Clematis Sandstone according to Fig . 6. But the rank of coal at Taurus, Baralaba and Moura do not correspond with the thickness . Considering from the depositional facies of coal seams and thickness and natures of sediments, it is presumed that the coals near or in the zone were buried in deeper place than other with some minor anomalous case, and the thickness of burial might have connection to quite an extent to the regional variation of rank.
As a conclusion, most important role had been played in the course of development of the basin from the begining and migration of centre of deposition to final accomplishment of the Dawson tectonic movement; the increase of pressure and geotherm during the deeper burial of coal seams and added heat and stressive pressure surpassing the statical pressure that occoured during the formation of the movement in the vicinity of the zone, would be effective functions in the course of coalification process .View full abstractDownload PDF (1060K) -
Toshihiko Maruyama1965 Volume 44 Issue 12 Pages 783-791
Published: December 20, 1965
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSFactors affecting on grindability of coal are as follows, 1) coal rank, 2) inorganic constituents, 3) micro-crackin coal, 4) coal petrographic constitution, etc.of these factors, it is discussed here how petrographic constitution affects on the grindability about seven Hokkaido coals.
Each coal sieved into 16×30 U. S. mesh was separated by float and sink method and each fraction was appropriated to proximate analysis, petrographic analysis and measurement of Hardgrove grindability index (H. I.).
From these experimental results it was observed that the statistical linear relation ships existed between H. I. and the volume of vitrite or vitrite+clarite. In case of low ash coal H. I. seems to be influenced by petrographic constitution, but scarcely influenced by ash content. Calculating H. I. of each microlithotype from correlation equations H. I.of vitrite is nearly equal to, or slightly greater than that of clarite, and H. I. of durite (durite I+durite II=exinite durite) is lower than that of vitrite and clarite.
In case of standardization of the Hardgrove method for Japanese coal, the coal showing narrow variation of petrographic constitution should be selected as the standard coal.View full abstractDownload PDF (979K) -
Shigemoto Tokunaga1965 Volume 44 Issue 12 Pages 792-796
Published: December 20, 1965
Released on J-STAGE: February 23, 2011
JOURNAL FREE ACCESSThe palynological work is one of the methods of investigation about ancient Plant concerned with nature of coal, and many results of pollen analyses on Japanese coal are obtained from the important coal fields in Hokkaido, Honshu and Kyushu.
According to the results, the pollens of broad leaved trees are found predominantly from Paleogene coal, and those of conifer and monocotyledon are also found. On the contrary, in Neogene coal, the conifer pollens are abundant.View full abstractDownload PDF (660K) -
In Comparison between HNO3Oxidation and O2 Oxidation on Wet ProcessSeiji Nishida, Michio Ikariya, Nobuyuki Kato, Isao Miyashita1965 Volume 44 Issue 12 Pages 797-805
Published: December 20, 1965
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSThe two oxidation reaction processes, which were performed by using 12.7% HNO3 or moderate pressure oxygen as oxidation reagents, were investigated by chemical and infra-red spectroscopic examinations of each product. The most noticiable differences in these two oxidation reactions were seen in reaction rate as well as selectivity of humic acid formation, namely, by means of HNO3 oxidation the humic acid was obtained rapidly and selectively.
And also it was found that there were some differences in the properties of the humic acids obtained by each oxidation method; the humic acid from O2 oxidative coal has larger cation capture capacity than the HNO3 humic acid, and the former is precipitated more easily from the alkali solution by adding dilute H2SO4 than the later.
These natures indicate that there exist some different processes in these two oxidation reactions.
The infra-red spectroscopic and elemental analyses of the oxidized coals suggest as follows;
1) In HNO3 oxidation, the fission of C-C bond in coal proceeds selectively through the addition of oxide of nitrogen to weak C-C bond, so that the humic acid is obtained in high yield.
2) In O2 oxidation, oxidative decompostion via surface oxidation proceeds partialy and can not distinguish from the fission of C-C bond in coal, so that the yield of oxidized coal decreases.
3) The difference of reaction rate between O2 and HNO3 oxidations might be reduced to the rate of fission of C-C and oxidation of alcoholic OH to carboxylic group.View full abstractDownload PDF (1037K) -
Masahiro Okamoto, Toshinori Ueda1965 Volume 44 Issue 12 Pages 806-814
Published: December 20, 1965
Released on J-STAGE: February 23, 2011
JOURNAL FREE ACCESSThe digestion process of bituminous coal in pitch oil and coal tar pitch of medium softening point (80-85°C R & B) at 270-280°C under at mospheric pressure was traced by means of measuring viscosity of the coal-pitch-pitch oil system with a penetrometer, and the mechanism of the process was discussed rheologically.
The test results suggested that the digestion process comprises, for the most part, simple swelling of coal particles.
Through solvent extraction of coal digestion pitch and redigestion of the extraction residue, the authors have not only recognized that the micelles of coal particles were not destructed to colloidal state, but also noted that the extraction residue was increased by swelling of coal particles during digestion process.View full abstractDownload PDF (1059K) -
the second report of coking experiment in high frequency oven with ultrasonic soundRyohei Takahashi, Kenjiro Takeshita1965 Volume 44 Issue 12 Pages 815-821
Published: December 20, 1965
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSThis paper deals at length with some results obtained from a series of coking experiments which has been continvously carried out, in order to obtain good coke for modern blast furnace from non-coking coals.
The equipment used for the experiment, or the way of carbonization is the same to those mentioned in the preceding paper, but the introducing way of ultrasonic wave into the coal of plastic state is different.
In the previous experiments ultrasonic wave had been directly introduced through the graphite conical horn into melted coal, resulting in that the figures of cokes obtained under the microscope were extremely complicated, and that we have met much difficulties to explain the effects of ultrasonic wave during carbonization. In the present experiments, however, the wave is also introduced through the same horn, not directly to melted coal, but to graphite or soft steel cover which is put on coal sample settled in graphite oven.The ultrasonic wave is thus converted in the stationary one and transported further into melted coal.
In this way, the effect of the ultrasonic wave in the coke figures becomes clearer, and the application of the wave for improvement on the nature of cokes is confirmed.View full abstractDownload PDF (1053K) -
Michio Shibaoka1965 Volume 44 Issue 12 Pages 822-829
Published: December 20, 1965
Released on J-STAGE: February 23, 2011
JOURNAL FREE ACCESSThin plates of Nisso coal composed of mineral durite and thin vitrite bands were ashed and the inorganic residues were melted. The individual characteristic alterations of ash laminas or mineral grains were microscopically observed.(P1.1-5)
Several kinds of minerals ground finely were mixed with the ash from the Nisso coal and were heated in the electric furnace. The temperature at which the disappearance of the mixed minerals and the secondary formed minerals took place were determined dy the X-ray diffraction method.(Fig.1)
Small cylindrical specimens of coal ashes and mixtures of coal ash and other minerals were heaetd in the electric furnace. With aid of 8mm cine camera the alteration in shape of specimens was recored. ed By evaluating height and diameter of the specimens on the screen height-diameter ratiocurves and expantion curves in relation to temperature were plotted.(Ftg.2-4) About the expansive shale, fly ash and their mixtures the same experiments were done.(Fig.5)
From the results of these experiments the following hypothesis is possible, that is the coal ash heated to high temperature can be supposed to be composed of the residual solid particles and the liquidus part. The fluidity or apparent viscosity of the coal ash depends on the content of the former and the viscosity of the latter. Quartz, hematite or magnetite and fly ash can be regarded as inert and solid material to some extent. This hypothesis seems to be too simple but it is applicable and useful in many cases.View full abstractDownload PDF (2044K) -
Tsunemasa Imaizumi, Toshio Inoue, Tsuneyoshi Narahara1965 Volume 44 Issue 12 Pages 830-837
Published: December 20, 1965
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSDealing with froth flotation of coal as a rate process from the kinetic point of view, the thesis is composed of study of the flotation characteristics of coal based on the kinetic consideration by Dr. Imaizumi and Dr. Inoue, which essentially relied on first order rate equation in which the rate constant k1, may not be single-valued but variant.
The effects of particle characteristics (i. e. size, specific gravity) on the rate constant k1 were investigated. The batch flotation experiments were carried out under the same condition using fifteen samples of different degrees of coalification, e. g., ten from domestic coal mines and five from foreign mines. It was ascertained that strong correlation exists between coalification rank and flotation rate, and that flotation rate constant had its maxi mum value on about 85% C (d. a. f.) in connection with Japanese samples. Considering chemical and physical characters and chemical structures of coal, the authors assumed that functional groups in coal structure have an important role in its surface wettability and that aromatic CH might be less effective on its flotation Lbehaviour than aliphatic one.View full abstractDownload PDF (981K) -
Hiroshi Tsukashima, Tsutomu Kato1965 Volume 44 Issue 12 Pages 838-844
Published: December 20, 1965
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSThe present report deals with the articial coalification of Tokachi and Tsuchiya lignites and Tenpoku coal which are the low-rank coal in Hokkaido coals, in order to make clear the constitution of the materials produced by the artificial coalification of them and the mechanism of the artificial coalification.
After 50g. of the powdered sample of those coals was placed in a stainless steel autoclave of shaking type (capacity 11.) with 400ml. of water, the air in the autoclave was replaced with nitrogen. Then the powdered sample in the autoclave was heated at 200, 250 and 300°C for 8, 24, 40 and 72hr. under gas-steam pressure at about 20, 50 and 120 atm.(gaug pressure).
The structural elements othose coals and the artificial coalification products of them were estimated by the van Krevelen's densimetric method for the structural analysis of coals. The composition of gas produced in the coalification was determined.
Then the artificial coalification of Tokachi lignite coincided with the natural coalification band of Hokkaido coals in the atomic H/C versus O/C diagram. It of Tsuchiya lignite advanced roughly along line describing the process of dehydration in that diagram. It of Tenpoku coal advanced between the two lines describing the process of artificial coalification of the others.View full abstractDownload PDF (749K) -
1965 Volume 44 Issue 12 Pages 845-848
Published: December 20, 1965
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSDownload PDF (582K) -
1965 Volume 44 Issue 12 Pages 852-855
Published: December 20, 1965
Released on J-STAGE: March 20, 2014
JOURNAL FREE ACCESSDownload PDF (545K)
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