燃料協会誌
Online ISSN : 2185-226X
Print ISSN : 0369-3775
69 巻 , 9 号
選択された号の論文の23件中1~23を表示しています
  • 高多 明
    1990 年 69 巻 9 号 p. 779
    発行日: 1990/09/20
    公開日: 2010/06/28
    ジャーナル フリー
  • 荒牧 寿弘
    1990 年 69 巻 9 号 p. 780
    発行日: 1990/09/20
    公開日: 2010/06/28
    ジャーナル フリー
  • 岩田 博行
    1990 年 69 巻 9 号 p. 781-786
    発行日: 1990/09/20
    公開日: 2010/06/28
    ジャーナル フリー
    Ever since the oil crisis coal conversion into heat, steam and elec-tricity has been pushed more intensively.
    A feed coal is required to meet the specified technical demands. In this circumst-ances the importance of coal grinding technology is increasing year by year.
    This review gives a brief look at the present state of coal grinding technology in which following items are dealt with:
    1. Required properties of feed coals to match specified targets.
    2. Pulverizing behaviours of coals in various grinding machines with different types of stresses.
    3. Product sizes as a function of input energy.
    4. Application of grinding kinetics on the comminution of coals.
    5. Other topics.
  • 木下 正昭, 山口 啓樹, 吉田 博久
    1990 年 69 巻 9 号 p. 787-790
    発行日: 1990/09/20
    公開日: 2010/06/28
    ジャーナル フリー
    Bowl Mills have been widely used for pulverizing various kind of solid fuels for various applications. It can produce the pulverized fuels of wide range of fineness from 65 to 95% through 200 mesh to meet the requirement of combustion equipments of various kinds. Its excellent fineness and perfect classification of coarse particles enabled the usage of hard burning fuels such as petroleum cokes and anthra-cite, widely expanding the horizon of fuel recourses.
    Owing to its effective grinding and classifying characteristics, internal recircula-tion of pulverized fuel inside the mill is reduced to minimum and operation of low air to fuel ratio is possible, which is generally required for low NOx combustion.
    Bowl Mill is also suitable for the production of slurry fuels because of its perfect elimination of coarse particles and low power consumption.
    Grinding rolls are of welded overlay type of super anti-abrasion materials and grinding surface can be rebuilt after worn.
    For its excellent performance, latest version of this Bowl Mill, MRS type with rot-ary separator received the 1989 award from Japan Society of Mechanical Engineers.
  • 藤岡 完造
    1990 年 69 巻 9 号 p. 791-795
    発行日: 1990/09/20
    公開日: 2010/06/28
    ジャーナル フリー
    Concerning to development and commercialization of CWM (Coal Water Mixture), grinding technology aim to fine grinding. In the demonstrative CWM plant furnished by KUBOTA Corp., TOWER MILLs are main functional component of fine grinding unit.
    TOWER MILL invented originally by Kubota Tower Mill Corp.(called “Japan Tower Mill Co., Ltd.” in former days) consists of vertical cylindrical body like as TOWER and rotating Screw. These components work like as Stirred type ball mill and can achieve fine grinding of materials. Result of the demonstrative operation of CWM plant was very successful. TOWER MILL ground coal from 1mm particle size to 87% through 75 microns for product, and produced CWM slurry with 68% density and 1000cps viscosity. Specific power consumption for TOWER MILL was 25-30kWh/t-CWM.
  • 藤田 豊久
    1990 年 69 巻 9 号 p. 796-800
    発行日: 1990/09/20
    公開日: 2010/06/28
    ジャーナル フリー
    The development of an improved sink-float testing apparatus us-ing a water based magnetic fluid and electromagnet for coal preparation has been discussed. The apparent density in the magnetic fluid can be regulated easily from 1200kg/m3 to 2200kg/m3 for coal analysis by controlling the current of the electromagnet. Therefore, it is possible to carry out the separation with a single cell and tested coal products need no washing for subsequent separation. Also the viscos-ity of the magnetic fluid is as low as 0.01Pa·s even at an apparent density of more than 2200kg/m3. The water based magnetic fluid used is non-toxic and does not react chemically with organic substance or inorganic impurities within the coal samples. The smeared water based magnetic fluid on the separated coals could be removed easi-ly by washing with water. The washed magnetic fluid, which became diluted, is con-centrated and returned to the separation cell.
  • 村田 逞詮
    1990 年 69 巻 9 号 p. 801-805
    発行日: 1990/09/20
    公開日: 2010/06/28
    ジャーナル フリー
    The main substances of this paper are summarised as follows.
    1. In an attempt to quantify the wettability of coal, the following two measuring methods were proposed, and the effectiveness of measured values of them were substantiated by a test.
    (1) Contact angle measuring method using molded pulverized coal
    (2) Dynamic wettability measuring method to utilize the capillarity in columnar pulverized coal
    2. The relationship between the wettability measured values by the above-mentioned measuring methods and coal properties is discussed and concludes as follows.
    (1) First, the coal wettability is greatly regulated by the ash content. To be more specific, coal is more hydrophilic the higher the ash content is.
    (2) In the wettability of coal organic substances, the direction in which the ox-ygen content ratio increases, particularly the direction in which functional group containing oxygen increases, is hydrophilic direction.
  • 森 祐行
    1990 年 69 巻 9 号 p. 806-812
    発行日: 1990/09/20
    公開日: 2010/06/28
    ジャーナル フリー
    Zeta potential measurements of coal are useful for the coal fines processing technology. It is important to find out why the different types of coal have different values of zeta potential at the same pH values of suspension. Although the zeta potential is the nature of the surface of the coal particles in suspension, we attempted to relate the zeta potential to their elemental components on the basis of the simplest idea that the chemical component ratio at the coal surface without any surface oxidation effect is proportional to that of the bulk chemical composition. The empirical equation of the relation between the zeta potential of the particles and the chemical components of coal samples was determined in aqueous suspension with different pH values. The equation is represented as follows:
    Z=BC×(C)+BH×(H)+BO×(O)+BN×(N)+BS× (S) +BA× (A) ,
    where Z is the zeta potential (mV) of the particles, (C), (H), (O), (N), (S) and (A) are weight percent of carbon, hydrogen, oxygen, nitrogen, sulphur and ash, respective-ly, and BC, BH, BO, BN, BS and BA are coefficients (mV %) of each respective components of the coal samples. Using the data of thirteen samples, the above coefficients were calculated numerically by the least square method in suspensions with different pH values. When the chemical components of a coal sample are known, the zeta potential of the coal fines can be determined by the equation with those coefficients.
  • 榎本 兵治
    1990 年 69 巻 9 号 p. 813-818
    発行日: 1990/09/20
    公開日: 2010/06/28
    ジャーナル フリー
    Danger of spontaneous combustion and dust explosion at coal handling and utilizing facilities is outlined.
    Spontaneous combustion is a resultant phenomenon of competition of the rates of heat generation and heat loss. Influence of factors on the initiation is described on the basis of the thermal explosion theory.
    Explosion characteristics of dust clouds are described in relation to the assessment and protection-suppression measures.
    It is emphasized that decreasing particle size increases the hazard of spontaneous combustion and dust explosion but there are little data for the assessment for finely pulverized coals.
  • 荷福 正治
    1990 年 69 巻 9 号 p. 819-822
    発行日: 1990/09/20
    公開日: 2010/06/28
    ジャーナル フリー
    Powders and transporting equipments are charged electrostatically in powder transportation. The static electrification is affected by the transport conditions, such as particle size, resistivity, transport concentration and velocity, relative humidity, etc. Spark discharge of the electrostatic charge might lead to the ignition of dust cloud.
    The relations between the transport condition and the electrification, and between the electrification and the dust explosion are reviewed in this report.
  • 北田 義之
    1990 年 69 巻 9 号 p. 823-827
    発行日: 1990/09/20
    公開日: 2011/02/23
    ジャーナル フリー
    coal is likely to generate a lot of coal dust, which is an important problem from the standpoints of both environment and quality control and therefore must be solved.
    Although grinding coal generates a lot of dust, the dust is usually confined in the closed-system grinding facility. Dust emission is a real problem in unloading, trans-porting and stocking coal.
    There are various methods to suppress dust emission.
    A dust collector is effective for local dust collection. For a wide area such as a coal terminal, on the other hand, compacting coal piles, spraying water over coal and/ or covering coal piles with sheet are widely used.
    Using surfactants is more effective in cost and suppressing coal dust than the other methods. There are two types of surfactants: permeable type and coating type. Because they work in different ways, it is important to select one of them considering coal type. stoking period, climate and/or working conditions.
  • 小川 仁, 柴田 和博
    1990 年 69 巻 9 号 p. 828-832
    発行日: 1990/09/20
    公開日: 2010/06/28
    ジャーナル フリー
    This paper will introduce the production technology of COM and CWM including the recent technology in our company.
    COM is made by the two lines of production facilities with capacity of 70t/h each and the annual production amounts to about 700, 000 tons.
    Based on the selection of the coals and additives and optimization of the coal particle size distribution, we are producing about 70, 000 tons of CWM annualy produced by two lines of production facilities with capacity of 15t/h each.
    We succeeded in development of the technology to produce super low ash (about 1.5%) CWM using Cerrejon coal. And then, We will perform the combustion test of the low ash CWM at Tomakomai from this August as a national project. We can also produce the CWM from high ash content coal. So we established the technology to produce CWM from bituminous coals ranging from one to thirties percent ash.
  • 平岡 泰次
    1990 年 69 巻 9 号 p. 833-839
    発行日: 1990/09/20
    公開日: 2011/02/23
    ジャーナル フリー
    To encourage small-and medium-sized energy users to use more coal, the Coal Cartridge System (CCS) Development Project was started in April 1984 by the CCS Promotion Association, which is chaired by Mr. Masaru Yamato, Chairman of Idemitsu Kosan.
    In the CCS, finely pulverized coal is packed together with inert gas into a tightly sealed container for direct transport to end users. The coal is not exposed to open air.
    This system eliminates the need for coal yards, makes coal transport much easier and eliminates the need for laborious ash disposal. CCS supply centers, where coal will be processed into granular fuel and then injected into cartridges, are to be built in various districts throughout Japan. The cartridges will be delivered by bulk lorry or container. Used cartridges will be recovered and brought back to the centers in the same way.
    The CCS Promotion Association completed a demonstration plant in 1984 at Tokuyama and a test boiler at Iwakuni in 1985, and finished the first phase of experimental test in September, 1987 as scheduled. From April, 1988, it is promoting the second phase of the technology for desulfurization in an easy way.
    Commercial use of this revolutionary system will make it possible to handle inexpensive coal as easily as heavy oil. This will be of great benefit to energy users, especially smaller companies that, up until now, have had virtually no access to coal because transportation and storage were seen as insurmountable problems.
  • 谷口 一徳
    1990 年 69 巻 9 号 p. 840-847
    発行日: 1990/09/20
    公開日: 2010/06/28
    ジャーナル フリー
    Since two “Oil Crises” in 1970's the consumption of steaming coal in Japan shows rapid increase, on the other hand source of imported coal has been widely spread, and number of coals amounts to more than hundred.
    Now it is important to investigate further relationship of coal characteristics and boiler performance in order to achieve high efficient and clean combustion in a view of the grobal environmental issue.
    So in this report, we introduce new indexes and approach for showing degree of combustibility, ash slagging property, electrostatic preciptability and grindability, and approach for clean and efficient combustion which we develop from coal supplyer view point.
  • 花下 和彦
    1990 年 69 巻 9 号 p. 848-851
    発行日: 1990/09/20
    公開日: 2010/06/28
    ジャーナル フリー
    Methanol-Slurry (CMS) is a new fuel composed of pulverized coal with suitable particle size and methanol.
    The Mitsui Coal Fluidization Consortiam was established by nineteen Japanese companies of the Mitsui group in 1980 and has been developing CMS as a new oil alternative energy. CMS technology is one of the coal fluidization technologies as well as those of Coal-Oil-Mixture and Coal-Water-Mixture.
    The purpose of our research and development is to establish technologies of total system CMS.
  • 奥原 捷晃
    1990 年 69 巻 9 号 p. 852-855
    発行日: 1990/09/20
    公開日: 2010/06/28
    ジャーナル フリー
    This paper describes the effect of coal pulverization on blast furnace coke making.
    Coal pulverization results in a lowering of the bonding power between coal particles, but it improves the dispersed condition of coal particles with different properties. This suggests that coke strength can be increased by coal pulverization if the bonding power between coal particles is compensated for by raising bulk density.
    As for formed coke making, the effect of coal pulverization on coke strength is large, because by briquetting, coal is carbonized under high bulk density. Particularly, by making coke structure fine and homogeneous, post-reaction strength is expected to improve.
    Carbonization of pulverized coal under agglomerated state makes optical anisotropic texture of coke homogeneous. Coal pulverization has the possibility of changing not only the physical properties but also the chemical properties of coke.
  • Toshiaki OKUHARA
    1990 年 69 巻 9 号 p. 855
    発行日: 1990/09/20
    公開日: 2010/06/28
    ジャーナル フリー
    This paper describes the effect of coal pulverization on blast furnace coke making.
    Coal pulverization results in a lowering of the bonding power between coal particles, but it improves the dispersed condition of coal particles with different properties. This suggests that coke strength can be increased by coal pulverization if the bonding power between coal particles is compensated for by raising bulk density.
    As for formed coke making, the effect of coal pulverization on coke strength is large, because by briquetting, coal is carbonized under high bulk density. Particularly, by making coke structure fine and homogeneous, post-reaction strength is expected to improve.
    Carbonization of pulverized coal under agglomerated state makes optical anisotropic texture of coke homogeneous. Coal pulverization has the possibility of changing not only the physical properties but also the chemical properties of coke.
  • 牧野 尚夫, 木本 政義, 佐藤 幹夫, 二宮 徹
    1990 年 69 巻 9 号 p. 856-862
    発行日: 1990/09/20
    公開日: 2010/06/28
    ジャーナル フリー
    In order to reduce NOx and the ignition loss generated by the pulverized coal combustion, the optimum two stage combustion method and the multistage air injection method is investigated at the pulverized coal combustion test facility (standard load: 6.54 × 105 kcal/hr).
    The location of the air injection for the two stage combustion is suitable at the case of distance position from the burner for the NOx reduction, but suitable at the case of near the burner for the ignition loss reduction. So, the location of the air injection has the optimum point. However the optimum air injection point is used, if the air rate for two stage combustion is very high, the regeneration of NOx by the recombustion at the two stage air injection point is occured. The air rate for the two stage combustion has the upper limit.
    The multi-stage air injection method devide the air injection point for the two stage combustion to control the re-combustion at the case of the high air rate for the two stage combustion, and the regeneration of NOx. So, the NOx reduction rate of the multi-stage air injection method is larger than that of the two stage combustion . The air injection point and the distribution of the air injection rate for the multi-stage air injection method have the optimum values similar with the two stage combustion for both of the simultaneous reduction of NOx and ignition loss.
    If the injection point and the distribution of the injection air rate are optimized NOx and the ignition loss emission are lowered than that of the two stage combustion.
  • 進藤 隆世志, 厳 建偉, 大沼 浩
    1990 年 69 巻 9 号 p. 863-869
    発行日: 1990/09/20
    公開日: 2010/06/28
    ジャーナル フリー
    The reactions of petroleum pitch with 2-chloropropane or propylene were carried out using phosphoric acid, sulfuric acid, trifluoromethanesulfonic acid and aluminum chloride as catalysts at temperatures in the range -10 to 200°C. The reactions of vacuum residue with 2-chloropropane were also studied using aluminum chloride catalyst at 25°C.
    Isopropylation of petroleum pitch was found to occur in the presence of trifluoromethanesulfonic acid or aluminum chloride catalyst. But phosphoric acid and sulfuric acid did not act as alkylation catalysts under the conditions studied (Tables 2, 3).
    H/C atomic ratio, toal weight, content of toluene soluble and content of pyridine soluble in the reaction products increased with increasing degree of isopropylation of petroleum pitch (Fig. 1).
    Structural parameters of original petroleum pitch and of its isopropylation products showed that isopropyl groups were introduced to petroleum pitch until about 80% of peripheral carbon atoms of polynuclear aromatic units were substituted by alkyl group (Fig. 2). It was expected that toluene insoluble fraction, which was higher molecular weight in the original petroleum pitch, was converted into toluene soluble fraction by isopropylation.
    In the case of Khafji vacuum residue, isopropylation did not proceed even by the use of aluminum chloride, and insolubilization took place instead of solubilization (Figs. 3, 4, 5).
  • 古田 毅, 丸山 勝久, 山田 能生, 白石 稔
    1990 年 69 巻 9 号 p. 870-874
    発行日: 1990/09/20
    公開日: 2010/06/28
    ジャーナル フリー
    Organic heavy components from five kinds of coal liquid vacuum residues (CLVR) from the plant (0.1t/d) of NEDOL process were studied to obtain a basic information for their utilization to carbon materials. The textures of cokes from extracts of CLVR and crystallographic parameters of graphitized cokes were examined by means of a polarized-light microscope and X-ray diffractometer.
    Cokes from asphaltenes showed flow anisotropic textures and ones from preas-phaltenes showed mosaic textures, which increased in the anisotropic unit size of the texture with increasing rank of the raw coal. Graphitizability of asphaltenes was bet-ter than that of preasphaltenes. Graphitizability of preasphaltenes became better with higher rank of the raw coals.
  • 蔵永 泰彦
    1990 年 69 巻 9 号 p. 875-884
    発行日: 1990/09/20
    公開日: 2010/06/28
    ジャーナル フリー
  • 神奈川機器工業株式会社
    1990 年 69 巻 9 号 p. 888
    発行日: 1990/09/20
    公開日: 2010/06/28
    ジャーナル フリー
  • 伊藤 司郎
    1990 年 69 巻 9 号 p. 889
    発行日: 1990/09/20
    公開日: 2010/06/28
    ジャーナル フリー
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