• 보존과학회지
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• 제3권1호
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• pp.13-18
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• 1994

Chemical analysis and metallographic observations of the iron slag were carried out in an attempt to estimate the old iron-making process. The slag containing $9.3\%\;TiO_2$ without Cu indicates that the ore used for smelting was sand iron, not rock ore. The phases identified in the slag were $ulv\ddot{o}spinel$, magnetite, $w\ddot{u}stite$, fayalite etc. This also supports the fact that the smelted ore was iron sand. The total amount of Fe and slag-making components$(=SiO_2+Al_2O_3+MgO+CaO)$ were $40.7\%\;and\;36.1\%$, respectively. These values were average ones found in the old slags formed in the ancient iron-making process. Assuming that $TiO_2$ in the ore combines with FeO, resulting in the formation of $ulv\ddot{o}spinel$, the estimated temperature of smelting was found to be about $1200^{\circ}C$.

• 암석학회지
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• 제18권4호
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• pp.307-314
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• 2009

아르헨티나 북부 후후이주에 분포하는 자플라 함철광체는 고생대 실루리아기 해성층에 배태되는 철광석(ironstone)형 철광상이다. 자플라 함철광체는 적철석, 차모사이트, 능철석으로 구성되며 특징적으로 어란상 조직을 보인다. 주 함철광물인 적철석은 운모류의 벽개 및 외각부를 교대하며 산출되어 광체 형성시 화학적 작용에 의해 철광체가 형성되었다. 아르헨티나 북부에는 고생대 실루리아기 분지가 다수 분포하며 이들은 잠재적인 철광상으로 생각되며 이들의 경제성은 함철층의 연장성 및 품위, 개발 심도에 따라 좌우 될 것으로 생각된다.

• 자원ㆍ환경경제연구
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• 제19권2호
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• pp.341-360
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• 2010

조선산업에서의 수요는 해상물동량이며 공급은 선박의 건조량이다. 따라서 해상물동량에 대한 정확한 예측은 향후 조선산업의 호 불황을 전망할 수 있는 중요한 요인이 된다. 본 연구의 목적은 해상물동량 중 가장 큰 비중을 차지하고 있는 건화물(철광석, 석탄)의 물동량을 전망하는 것이다. 철광석 물동량의 예측을 위하여 조강생산과 세계 GDP를 독립변수로, 석탄 물동량 예측을 위하여 조강생산과 세계 발전량을 독립변수로 하는 회귀식을 도출하였으며, 두 회귀식 모두 통계적으로 유의하다는 결론을 얻었다. 전망 결과, 2010년 철광석 해상물동량은 2009년 대비 5.1% 증가한 8억 9,200만 톤 수준이 될 것으로 전망되었으며, 석탄은 전년대비 6.1% 증가한 8억 2,700만 톤 수준이 될 것으로 전망되었다. 2015년까지의 중기 전망(2009~2015)은 철광석이 연평균 4.7%, 석탄이 6.1%의 증가세를 보이는 것으로 나타났다. 전체 해상물동량에서 가장 비중이 큰 두 화물의 해상물동량에 대한 예측은 향후 해운경가와 조선경기의 향방을 가늠해 볼 수 있는 중요한 정보를 제공한다는 점에서 본 연구의 의미가 있다.

• The Korean Journal of Ceramics
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• 제2권3호
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• pp.125-130
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• 1996

Hematite iron ore and waste iron oxide sludge containing about 3-5 wt% $SiO_2$ were purified by three types of method developed on the basis of the Bayer process which is known as the purification process of bauxite ore. The basic principle of the developed methods lies in the fact that the impurities contained in the iron oxides, such as $SiO_2$ and $Al_2O_3$ are soluble in the alkaline reagents. Reaction of the raw materials with KOH was done in pressure vessel, at atmospheric pressure, and by both of these two. By the pressure vessel method $SiO_2$ content was reduced to below 0.5 wt% in the waste iron oxide sludge, while, in iron ore, $SiO_2$ remained at 2-3 wt%. The atmospheric pressure reaction rendered the waste iron oxide sludge $SiO_2$ content below 0.5wt% when the reaction temperature increased to above 90$0^{\circ}C$. The combined method of two previous methods was the most effective process and rendered the refined iron oxide about 300-400ppm of $SiO_2$. Using some refined iron oxides, Ba-ferrite was produced and magnetic properties were measured. The highest quality of magnetic properties obtained in this study were Br=2.09 G, bHc=1.99 KOe, iHc=4.54 KOe, $(BH)_{max}$=1.06 MGOe. Effect of sintering condition and chemical composition will be discussed.

• 자원환경지질
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• 제2권2호
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• pp.53-67
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• 1969

Magnetite deposit of Pocheon Iron Mine is a contact replacement skarn deposit embedded in the carbonate rocks (limestone and dolomite) which are intruded by granite porphyry. The shape of ore bodies is sweet potato-like and/or irregular massive form; D-ore body, the biggest one is of $180m{\times}40m{\times}200m$ in size. The ore is in general of high grade. The location of the ore bodies is controlled by the fault which strikes north south and dips $60^{\circ}$ to $70^{\circ}$ to the west. A regular distribution of mineralized zones is recognized in order of outward (hanging wall side) from granite porphyry as follows: compact fine-grained skarn, limesilicates, magnetite ore body, marble, limesilicates, pyritized meta-sediments.

• 자원환경지질
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• 제8권3호
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• pp.165-168
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• 1975

The grade and recovery rate and its sulphur content of iron concentrate compared respectively as varied with redcued size using the Crocket Magnetic Separator and the Wet-Drum-Magnetic Separator in the magnetic separation test of iron ore from Yangyang mine. The content of sulphur was decreased distinctly as the size was finer. In case of the sample of -100 mesh, using the Crocket Magnetic Separator, the sulphur content of iron ore was decreased to 0.10% and its grade increased to 67.0%, but the recovery rate was no more than 85.1%. In the Wet-Drum type, the grade and the recovery rate of concentrate was better than those in the Crocket Magnetic Separation, but the content of sulphur was more than that in the Crocket Magnetic Separation. The Crocket type is suitable for less sulphur content while the Wet-Drum Magnetic Separator is suitable for better the grade recovery rate of the magnetic concentrate.

• 자원환경지질
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• 제12권1호
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• pp.13-15
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• 1979

Iron ore waste discarded around Choong-ju iron district, Choongchong-Bukdo is as low as 25 per cent of iron, mainly consisting of hematite and magnetite. In this mineral dressing test procedure 93 per cent of magnetite was separated and concentrated into the magnetite concentrate as high as 62 per cent. The remaining sample, mostly, hematite averages about 19.8 per cent of iron which can be concentrated with very good results with the optimum flotation conditioning-pH 3.0 and 3 cc per litre of aero-promoter #845 (0.5% sol.) and 1.5cc per litre of hydro-fluoric acid (40% sol.) and four times of cleaning flotation. Hematite concentrate averages 64.2 per cent of iron. The overall iron concentrate averages 63 per cent of iron with recovery 86 per cent of iron contained.

• 대한조선학회 특별논문집
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• 대한조선학회 2015년도 특별논문집
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• pp.85-92
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• 2015

In general, when ships are designed, structural strength and fatigue strength must be verified based on the relative rules respectively. In case of Slurry Iron Sand Carrier designed to carry Iron-Sand saturated at water content, there is no special consideration of fatigue strength analysis. However, this vessel is similar to Ore Carrier in consideration of the overall characteristics of loaded cargo and the shape of cargo hold. Therefore we verified fatigue strength based on fatigue analysis procedure of ore carrier in DNV Rules and carried out the study for improving of fatigue strength of Slurry Iron Sand Carrier.

• Geosystem Engineering
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• 제21권5호
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• pp.262-272
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• 2018

The U-statistic method is one of the most important structural methods to separate the anomaly from background. It considers the location of samples and carries out the statistical analysis of the data without judging from a geochemical point of view and tries to separate subpopulations and determine anomalous areas. In the present study, 3D U-statistic method has been applied for the first time through the three-dimensional (3D) modeling of an ore deposit. In order to achieve this purpose, 3D U-statistic is applied on the data (Fe grade) resulted from the drilling network in Baghak mine, central part of the Sangan iron mines (in Khorassan Razavi Province, Iran). Afterward, results from applying 3D U-statistic method are used for 3D modeling of the iron mineralization. Results show that the anomalous values are well separated from background so that the determined samples as anomalous are not dispersed and according to their positioning, denser areas of anomalous samples could be considered as anomaly areas. And also, final results (3D model of iron mineralization) show that output model using this method is compatible with designed model for mining operation. Moreover, seen that U-statistic method in addition for separating anomaly from background, could be very efficient for the 3D modeling of different ore type.

• 한국항해항만학회지
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• 제44권2호
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• pp.128-135
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• 2020

Long-term shipping contracts represent the cooperative and coexisting relationships between the shipping and steel industries. Yet, differences between the contract forms for iron ore and steel products have emerged. Specifically, the large proportion of consecutive voyage charters (CVC) is being applied in the iron ore trade, whereas the contract of affreightment (COA) is proportionally higher for shipping steel products. The literature review and in-depth interviews in this study identified through the research model, the characteristics of the shipping and market structure in both markets have significantly contributed to the preference of different long-term contracts. It has been determined that the mutual oligopoly market structure and the characteristics of shipping such as, the small number of suitable vessels in the market, the single fixed load/discharge ports, the long-distance voyages, and the potential risks for fatal accidents because of cargo liquefaction, for the iron ore trade, provide higher contribution to the preference of CVC contracts. In contrast, the consignor oligopoly market structure and the shipping characteristics, such as the greater number of suitable vessels available in the market, the variation in ports, the cargo quantity per shipment, the various load/discharge ports, and the need for experienced carriers for steel product loading in the steel product trade has shown higher preference on the COA contracts as the consignors with superiority over the shipowners, resulting in favorable contract types and conditions for the consignors.