All issues
Successor
Volume 49, Issue 10
Displaying 1-8 of 8 articles from this issue
- |<
- <
- 1
- >
- >|
-
[in Japanese]1970 Volume 49 Issue 10 Pages 711
Published: October 20, 1970
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSDownload PDF (1880K) -
Shoji Iki1970 Volume 49 Issue 10 Pages 712-717
Published: October 20, 1970
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSThe Japanes iron and steel industry has expanded at a faster pace, withan output of 22, 000, 000 tons in 1960, 66, 000, 000 tons in 1968, and is expected to produce 103, 230, 000 tons in 1972. According, the demands for imported coal to meet those iron and seer requirements are estimated to be 41, 000, 000 tons in 1970, and 54, 000, 000 tons in 1972, assuming domestic coking coal products to be 11, 000, 000 tons.
Coal demands growing in explained by data of the Ministry of International Trade and Industry.View full abstractDownload PDF (756K) -
Sadaharu Toyoda, Junjiro Kumai, Kiyoshi Yamaguchi, Katsuhisa Maruyama1970 Volume 49 Issue 10 Pages 718-728
Published: October 20, 1970
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSBy using the pilot plant reported previously with a double roll press in stead of a rotary table type briquette machine, the green briquettes were made from various kinds of coal including foreign coal. In order to obtain an adequate condition for heating the green briquettes by hot sand, many tests were carried out for the green briquettes heating by an electric furnace. Moreover, the green briquettes were heated by mixing with hot sand. The coefficient of contraction for the green briquettes after pre-heating was measured in order to see the effect of pre-heating. The properties of green briquettes and of the formed cokes were described and some explanation for the results also given in this paper. Main results obtained are as follows.
(1) Non-caking coal and caking coal were heated separately in two fluidized bed retorts at about 550-600°C and about 200-250°C, respectively. After mixing and forming them the properties of green briquettes are volatile matter 15-25%, apparent density 1. 15-1. 30, trommel index 80-90%.
(2) The Formed cokes were obtained by heating the green briquettes using the electric furnace with slowly raising up temperature (3-5°C/min), or putting them into the electric furnace (650-750°C) for about 1. 5-2 hours and moreover another electric furnace at 900°C for abont 40 minutes. The properties of the formed cokes are apparent density 1. 15-1. 40, drum index 90-94.
(3) The adequate conditions for heating the green briquettes by hot sand were deduced about the factors of hot sand such as the temperature, the quantity and so on.View full abstractDownload PDF (1458K) -
Yuji Yoshida, Hiroshi Yamaguchi, Midori Yumiyama, Toshimasa Hirama, Ta ...1970 Volume 49 Issue 10 Pages 729-735
Published: October 20, 1970
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSAt the Government Industrial Development Laboratory, Hokkaido, the process consisting of low-temperature carbonisation and hot briquetting followed by high temperature carbonisation is being investigated to convert non-or slightly caking coals into metallurgical coke and also to develop a continuous coke-making process. It is based on the technique for making solid smokeless fuel reported previously.
This paper relates to low-temperature carbonisation and hot briquetting carried out with a pilot plant of 250kg/hr.
Coking coals blended with 30 to 50 per cent of slightly caking coals of 1 to 11/2 in free swelling index are crushed and carbonized at 410-450°C in a fluidized bed carbonizer provided with a stirrer. Hot fine coals are formed while still hot by a double roll press.
At first air was used as a fluidizing gas and then it was replaced by hot inert gas. Bed temperature was controlled within ±5°C by means of automatic feed control. In this way, briquet coke high in strength became obtainable.
Secondly, a pre-heater of fluidized bed was added in series before the carbonizer. Though the effects of shortening of residence time in the carbonizer on coke quality were little recognized, the capacity of the carbonizer was much increased. From these results, a compound fluidized carbonizer was proposed.
As regards high temperature carbonisation, a fluidized medium carbonizer of horizontal type is still in the stage of laboratory scale, experimental results being briefly described.View full abstractDownload PDF (969K) -
Yasuo Okuyama, Takashi Miyazu, Hidehiko Sugimura, Mitsuteru Kumagai1970 Volume 49 Issue 10 Pages 736-743
Published: October 20, 1970
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSWe attempted the application of Schapiro's method to the prediction of Drum Index of coke made by many kinds of single coal, Informations obtained are as follows;
1) It is possible to predict the DI from from the petrographic study of coal, but the precision of the estimation was not so good, though high correlation was found between estimated DI3015 and determined DI3015, (r=0. 92**).
It suggests that the property presented by Drum Test is differ from that of Tumbler Test. It is necessary, therefore, to perform more detailed studies to obtain the precise prediction system of DI3015.
2) It was not impossible to predict the micro-strength or reactivity of coke from the petrographic study of coal, but the precision of the estimation was also not so good.
3) Various coking coals can be stratified by two parameter-Reflectance of Vitrinites and Gieseler max. fluidity of coal-.
This statifying system is useful to pre-evaluation of coking coals, especially in the case of large quantity of sample can not be obtained.View full abstractDownload PDF (2189K) -
Hidehiko Sugimura, Mitsuteru Kumagai, Hideo Kimura1970 Volume 49 Issue 10 Pages 744-751
Published: October 20, 1970
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSThe changes of anisotropic texture of foreign coals were examined.
It was showed that anisotropic texture from Vitrinite is equal to Japanese coals.
In medium volatile coals, first star structure appeared, then it was changed to fibrous texture.
In low volatile coals, the changes from droplet to completely fibrous texture was shown.
Anisotropic texture from inert maceral are classified into Fusitelike and Fragmentary texture.
Quantitative analysis of anisotropic texture was examined about coke, which produced in 250kg standard test coke oven.
Good correlation was established between anisotropic texture and coke qualities.
We insisted that the study for inprovement of coke quality had to pursue the change of anisotropic texture during plastic state.View full abstractDownload PDF (6535K) -
Hideo Kimura, Yuzo Sanada, Sachiko Sugawara, Takeshi Furuta, Hidemasa ...1970 Volume 49 Issue 10 Pages 752-765
Published: October 20, 1970
Released on J-STAGE: October 21, 2011
JOURNAL FREE ACCESSThe formation of spherical bodies obtained by so lidification from the plastic zone of liquid phase in the early stage of carbonization of coals, pitches and phenol-folmaldehyde resins were studied with polarized-light microscopic examination.
The nucleation and growth of spherical bodies occur progressively with increase of residence time at a fixed temperature, until the spherical bodies coalesce with each other. For example, the appearance of spherical bodies in naphtha-tar pitch can be observed at a low temperature such as 350°C for 20hrs.
In general, it was observed that non-graphitizing carbons have usually the isotropic texture, but graphitizing carbons have the anisotropic texture under the microscope.
As a result, we have recognized the formation of spherical bodies have an effect on the chemical composition of organic compounds and the residence time, that is to say, birth and breeding.
As the existance of oxygen in coals and sulfer in pitches very affect to the develop-ment of anisotropic spherical bodies, consisting of planar aromatic compounds of high molecular weight, separated from the isotropic plastic zone, it is proposed that the O.N.S obstruction is the negative element for carbonization and graphitization.
In the end, when the organic compounds are carbonized and graphitized in various temperature, the examination by using of microscope on the anisotropic texture of spherical bodies at the temperature range from 350 to 450°C of early stage of carbonization can be previously predicted the natures and structures of carbons obtained by the heat treatment of high temperature such as 2, 500 to 3, 000°C.View full abstractDownload PDF (15162K) -
1970 Volume 49 Issue 10 Pages 776-786
Published: October 20, 1970
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSDownload PDF (1484K)
- |<
- <
- 1
- >
- >|