• Title/Summary/Keyword: anthracite

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On the Graphitic Properties of Korean Anthracite (II) X-ray Diffraction Method as an Estimation of the Graphitic Properties of Anthracite (石炭의 黑鉛性에 關한 硏究 (第2報))

  • Sin Sup Oh;Suk Won Lee;Changmoo Lee
    • Journal of the Korean Chemical Society
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    • v.7 no.2
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    • pp.182-185
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    • 1963
  • In the previous paper of the series of researches on the graphitic properties of anthracites, authors have already reported the results on the electrical specific resistance measurements for Korean anthracites in order to develope a simple methods which differentiate graphite from anthracite. In this paper, the X-ray diffraction method and oxidation have been applied and compared with the results which were obtained by the specific resistance measurements in the previous paper. It has been confirmed that there is a parallel relation between the value of specific resistance measurement and height of hexagonal peak by X-ray diffraction, but the color reaction due to graphitic acid by oxidation does not show any definite critical points between graphite and anthracite.

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A Study on the Combustion Characteristics of Coke and Anthracite in an Iron Ore Sintering Bed (소결층 내에서의 코크스와 무연탄의 연소 특성 비교 연구)

  • Yang, Won;Yang, Kwang-Heok;Choi, Eung-Soo;Ri, Deog-Won;Kim, Sung-Man;Choi, Sang-Min
    • Journal of the Korean Society of Combustion
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    • v.9 no.2
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    • pp.30-37
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    • 2004
  • Coal combustion in an iron ore sintering bed is a key parameter that determines quality of the sintered ores and productivity of the process. In this study, effects of the different types of coal - coke and anthracite - on the combustion in the iron ore sintering bed are investigated by modeling and experiment. Fuel characteristics of coke and anthracite are observed through a set of basic analysis and thermo-gravimetric analysis. Coke has a higher reactivity than anthracite due to the difference of surface area and density, and these characteristics are reflected in the 1-D unsteady simulation of the iron ore sintering bed. Calculation results show that different reactivity of the fuel can affect the bed combustion.

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A Study on the Combustion Characteristics of Coke and Anthracite in an Iron Ore Sintering Bed (소결층 내에서의 코크스와 무연탄의 연소 특성 비교 연구)

  • Yang, Won;Yang, Kwang-Hcok;Choi, Sang-Min;Choi, Eung-Soo;Ri, Deok-Won;Kim, Sung-Man
    • 한국연소학회:학술대회논문집
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    • pp.141-148
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    • 2004
  • Coal combustion in an iron ore sintering bed is a key parameter that determines quality of the sintered ores and productivity of the process. In this study, effects of the different types of coal coke and anthracite - on the combustion in the iron ore sintering bed are investigated by modeling and experiment. Fuel characteristics of coke and anthracite are observed through a few basic analysis and thermo-gravimetric analysis. It was found that coke has a higher reactivity than anthracite due to the difference of surface area and density. Those characteristics are reflected to the 1-D unsteady simulation of the iron ore sintering bed. Calculation results show that different reactivity of the fuel can affect the bed combustion, which implies the further investigation should be performed for obtaining optimal combustion conditions in the sintering bed.

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A Study on Gasification Reaction and Strength of Foundry Coke and Lump Anthracite Coal (주물용 코우크스와 무연괴탄의 가스화 반응과 강도에 관한 연구)

  • Cho, Nam-Don;Kim, Jong-Hoon
    • Journal of Korea Foundry Society
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    • v.9 no.3
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    • pp.247-256
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    • 1989
  • The gasification reaction rates by $CO_2$ in $CO/CO_2/N_2$ of various compositions in the temperature range of $900-1200^{\circ}C$ were measured for foundry coke and anthracite lump. The data for the rates was analyzed with Langmuir-Hinshelwood rate equations for the gasification of carbonaceous specimens. The values of the apparent activation energies of the reactions obtained from these data were ranged to be 47-99 and 73-128Kcal/mol respectively for foundry coke and for anthracite lump. The major contribution to decrease in tensile strength was shown to be attributable to the enlarging of the macropores in the coke and that of crack in the anthracite lump. Under the same experiment of the gasification of foundry coke, the rate of form coke was increasing as the addition of $Fe_2O_3$ increases.

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Effect of Fly Ash on the Yield and Quality of Tobacco (석탄회 시용이 연초의 수량 및 품질에 미치는 영향)

  • 홍순달;석영선
    • Journal of the Korean Society of Tobacco Science
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    • v.19 no.2
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    • pp.92-101
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    • 1997
  • This study was conducted to investigate the effect of fly ash on the yield and quality and to determine the optimum application amount of fly ash for tobacco(Nicotiana tabacum L). Two kinds of fly ash, anthracite and bituminous coal, were treated with different levels of 0, 20, 40, 60 MT/ha. Dry weights of tobacco at middle and topping growth stage were increased with application of fly ash, showing the highest dry weight at 40 MT/ha in both kinds of fly ash. It was showed that the bituminous coal had a little more effective for yield than that of anthracite. Comparing with the control, yields of tobacco applied with fly ash were significantly increased about 17.7% and 17.1% by the application of bituminous coal and anthracite, respectively. Quality of flue-cured leaves was better by application of fly ash than that of the control. The quality index was given the highest at 40 MT/ha for bituminous coal increasing by 24.6% and at 60 MT/ha fur anthracite increasing by 13.4% compared with the control. The economical efficiency considered of the yield and quality of tobacco was the highest at 40 MT/ha of bituminous. Soil pH, contents of available P2O5, organic matter, exchangeable Ca2+ and Mg2+ of soil during the growing season were increased by application of fly ash, showing more effectiveness in bituminous than that in anthracite. By the application of fly ash, the nutrients availability and the acidity of soil were reformed and they caused significantly the increase of growths yield, and quality of tobacco. By the application of lime reforming soil acidity, growth response, yields and quality of tobacco were not increased compared to the control, although the effect of reforming soil pH was remarkable.

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A Study on Production of Air Pollutants and Combustion Efficiency of Anthracite-Bituminous Coal Blend Combustor Using Fluidized Bed (유동층을 이용한 유,무연탄 혼합 연소로에서 대기오염물질 생성과 연소효율 연구)

  • Cho, Sang-Won;Min, Byoung-Chul
    • Applied Chemistry for Engineering
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    • v.8 no.3
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    • pp.517-523
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    • 1997
  • We have been studied that combustion efficiency and the production of air pollution of anthracite-bituminous coal blend in a fluidized bed coal combustor. Also, the reaching time of steady state condition have been studied. This experimental results are presented as follows. As the height of fluidized bed combustor becomes higher, the concentrations of $SO_2$ and NOx mainly increased. Also, as anthracite fraction increased, the emission of $SO_2$ concentration was increased but, the variation of $NO_X$ concentration was negligible according to anthracite fraction. When anthracite fraction ratio was increased, elutriation rate was increased and exit combustible content over feeding combustible content was increased. Regardless of anthracite fraction ratio the uncombustible weight percentage according to average diameter of elutriation particles were approximately high in the case of fine particles. Over bed temperature $850^{\circ}C$ and excess air 20%, the difference of combution at the velocity 0.3m/s, bed temperature $850^{\circ}C$, the excess air 20%.

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Analysis of Combustion Characteristics of Bituminous and Anthracite Coal in a Fluidized Bed Combustor (유동층연소로에서 유연탄과 무연탄의 연소특성 해석)

  • Jang, Hyun Tae;Park, Tae Sung;Hong, Sung Chang
    • Applied Chemistry for Engineering
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    • v.10 no.4
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    • pp.586-591
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    • 1999
  • Mixed-firing of a bituminous and an anthracite coal carried out in a batch fluidized bed combustor(0.109 m-I.D., 0.9 m-height). Effect of particle size an mixing fraction of anthracite and bituminous coal combustion characteristics were studied. The temperature profiles and pressure fluctuation properties were measured to interpret the combustion characteristics in a batch fluidized bed combustor. The used domestic anthracite coal has heating value of 2010 kcal/kg and the imported high-calorific bituminous coal has heating value of 6520 kcal/kg. The combustion characteristics in a batch fluidized bed combustor could be interpreted by using pressure fluctuation properties and temperature increasing rates. It was found that the optimum anthracite mixing percentage could be predicted analyzing the combustion rate and fluidization characteristics, The optimum mixing fraction was about 30 %. The different burning region of fluidized bed combustor was measured by temperature increasing rates.

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Effect of Boiler Operating Conditions on the Generation of Unburned Carbon in Anthracite Co-fired 500 MW Thermal Power Plant (무연탄 혼소 500 MW 석탄화력발전소에서 보일러 운전조건이 미연탄소 발생에 미치는 영향)

  • Nam, Jeong-Chul;Yoo, Ho-Seon
    • Plant Journal
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    • v.14 no.3
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    • pp.35-41
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    • 2018
  • Considering the recent government policy toward North Korea and situation of power facilities in North Korea, it will be necessary to prepare for the consumption of the anthracite coal from Korea in coal-fired power plants. In this study, the anthracite co-fired tests in 500 MW thermal power plants were conducted with varying the main operation conditions, such as anthracite injection position in the boiler, coal fineness and combustion air flow, to investigate the effects on the generation of unburned carbon. It was confirmed that the generation of unburned carbon was remarkably reduced when the anthracite coal was injected into the boiler low burner with a relatively long residence time in the main combustion region, and that the increase of the coal fineness proportional to the combustion reaction surface area also reduces the generation of unburned carbon. An increase in the combustion air flow, which increase the combustion reactivity, also contributes to the reduction of unburned carbon. It is possible to maintain the unburned carbon generation below 5 % of the ash recycling quality by controlling the above operating conditions for the given mixing rate of anthracite, and the priority of changing the operating conditions within the test range is the highest for anthracite coal injection position.

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Property of the Jurassic anthracite (Anthracite from the Seongju Area of the Chungnam Coalfield) (충남탄전(忠南炭田) 무연탄(無煙炭)의 특성(特性))

  • Park, Suk Whan;Park, Hong Soo
    • Economic and Environmental Geology
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    • v.22 no.2
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    • pp.129-139
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    • 1989
  • The anthracite coalfields of Korea are confined to the areas where sedimentary rocks of Permian and Jurassic are preserved. The Chungnam coalfield lies in the sedimentary rocks of Jurassic which belongs to the Daedong Supergroup (the Nampo group). For the property analysis of each coal seam interbeded in Daedong Supergroup, Seongju area is chosen and twelve coalseams are taken. Many standard tests have been established for optical analysis (maceral analysis, coalification degree measurement), chemical analysis (proximate, ultimate analysis) and physical analysis (ignition temperature, ash fusion temperature, hardgrove grindability index and X-ray diffraction). The Jurassic anthracite mainly consist of vitrinite and macrinite and the range of the reflectance is $R_{max}$ 5.0-6.5 which means metaanthracite rank. By the chemical composition analysis, it shows low H/C and high O/C value compare with international average value. By the physical analysis, it has very high ignition temperature ($531-584^{\circ}C$) and ash fusion temperature ($1510-1700^{\circ}C$) and very low combustion velocity (0.2-1.9 mg/min). The very wide range of the hardgrove grindability index (46-132) means that the grindability controlled mainly by the structural conditions of coal bearing strata.

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Co-combustion Characteristics of Mixed Coal with Anthracite and Bituminous in a Circulating Fluidized Bed Boiler (순환유동층 보일러에서 무연탄-유연탄의 혼합연소 특성)

  • Jeong, Eui-Dae;Moon, Seung-Jae
    • Plant Journal
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    • v.6 no.2
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    • pp.70-77
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    • 2010
  • This study investigated the characteristics of co-combustion of mixed anthracite (domestic and Vietnam) and bituminous coal (Sonoma, Australia) at circulating fluidized bed boiler in Donghae thermal power plant when mixing ratio of bituminous coal is variable. Co-combustion of bituminous coal contributes to improvement in general combustion characteristics such as moderately retaining temperature of furnace and recycle loop, reducing unburned carbon powder, and reducing discharge concentration of NOx and limestone supply owing to improvement in anthracite combustibility as the mixing ratio was increased. However, bed materials were needed to be added externally when the mixing ratio exceeded 40% because of reduction in generating bed materials based on reduction in ash production. When co-combustion was conducted in the section of 40 to 60% in the mixing ratio while the supplied particles of bituminous coal was increased from 6 mm to 10 mm, continuous operation was shown to be possible with upper differential pressure of 100 mmH2O (0.98 kPa) and more without addition of bed materials for the co-combustion of mixed anthracite and bituminous coal (to 50% or less of the ratio) and that of domestic coal and bituminous coal (to 60% of the ratio).

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