• 한국세라믹학회지
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• 제30권7호
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• pp.557-562
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• 1993

Following conclusions are made from the detalied research on the relation between the phase change of the petroleum raw cokes after ball milling and the preheat treatment temperature. The petroleum raw cokes species are preheated in the temperature range of 350~45$0^{\circ}C$. At the preheat treatment temperature of 40$0^{\circ}C$ the particles of petroleum raw cokes from ball milling become spheically shape with the almost uniform particle size distribution of 1~5${\mu}{\textrm}{m}$. At the same temperature, they became low-graphitized with the d0.02 X-ray diffraction index of 3.41$\AA$. The carbon material made from the petroleum raw cokes at 40$0^{\circ}C$ turned out to have the good modulus of rupture about 600kg/$\textrm{cm}^2$, with the bulk density around 1.8g/㎤ and the appearent porosity around 8%.

• 한국세라믹학회지
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• 제34권4호
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• pp.413-419
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• 1997

The specimens which were prepared from cokes with additions of 0~25 wt% B4C were sintered in Ar atmosphere at 220$0^{\circ}C$. The effects of B4C content on graphitization and oxidation resistance of cokes were investigated. B4C accelerates the graphitization of cokes and at 220$0^{\circ}C$ the degree of graphitization increased from 0.33 which is the value of pure carbon to 0.56, which increased bluk density and porosity. Especially bending strength increased as th graphitization temperature increased. Oxidation resistance property was greatly improved when B4C was added more than 10wt% at 80$0^{\circ}C$ and when B4C was added more than 20wt% at 100$0^{\circ}C$. This was because that the thin layer of B2O3 glass phase on the surface of the composite could be identified to increase the oxidation resistance.

• 한국기계연구소 소보
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• 통권20호
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• pp.105-114
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• 1990

The relationship between the properties of two kinds of calcined cokes and graphitized forming bodies were examined. The microstructures of the forming bodies are already determined to some degree at the stage of baking. Calcined cokes as well as baked forming bodies using the same coke as filler were heat treated at various temperatures and their structural and properties changes with heat treated temperature were studied. The transition in properties changes with heat treatment in forming bodies were observed around $2000^{\circ}C$. The characteristics of the finial graphite bodies are strongly dependent on the properties of the raw material cokes.

• 대한화학회지
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• 제4권1호
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• pp.78-80
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• 1957

Up to now, only superficial studies on the combustion velocity of smokeless fuels have been reported, while it should be a basical factor on the utilization of low quality coals and some other smokeless solid fuels. It was, therefore, difficult to choose raw material coals in manufacturing gaseous fuels. With the intent to solve above problem, we have determined combustion velocity of domestic anthracites, graphites, coalites of lignite and cokes from Japanese bituminous coal. The results show that the cokes from Japanese bituminous coal which has been used as raw material in the manufacturing gaseous fuels such as water gas, or producer gas in Korea can be replaced by some sources of domestic anthracite or coalite of lignite.

• 한국연소학회지
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• 제7권3호
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• pp.23-31
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• 2002

Processes in an iron ore sintering bed can characterized as a relatively uniform progress of fuel, cokes combustion and complicated physical change of solid particles. The sintering bed was modelled as an unsteady one-dimensional progress of the fuel layer, containing two phases: solid and gas. Coke added to the raw mix, of which the amount is about 3.5% of the total weight, was assumed to form a single particle with other components. Numerical simulations of the condition in the iron ore sintering bed were performed for various parameters: moisture contents, cokes contents and air suction rates, along with the various particle diameters of the solid for sensitivity analysis. Calculation results showed that the influence of these parameters on the bed condition should be carefully evaluated, in order to achieve self-sustaining combustion without high temperature section. The model should be extended to consider the bed structural change and multiple solid phase, which could treat the inerts and fuel particles separately.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2001년도 ICCAS
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• pp.174.6-174
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• 2001

Various raw materials from which iron and steel are made are unloaded from ship and then piled up at the designated yard. The equipment that piles up the raw materials is called Stacker and these materials are then dipped out and sent to unit factories such as blast furnace and cokes using the equipment called Reclaimer. The Reclaimer has an actual size of 16 meter high and 50 meter long and runs back and forth over the rail of about 1.2 km, carrying the materials to each unit factory. Until now, in most cases, Stacker and Reclaimer are manually operated. At POSCO, four workers on a shift basis sit in the operation room as shown in the picture, pile up and dip out the materials, checking them out with their own eyes ...

• 한국연소학회:학술대회논문집
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• 한국연소학회 2001년도 제23회 KOSCO SYMPOSIUM 논문집
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• pp.161-168
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• 2001

Sintering bed of iron ore in the steel making process is one of typical applications of solid fuel bed, which has relatively uniform progress of fuel and simple processes of combustion. The sintering bed was modelled as an unsteady one-dimensional progress of fuel layer containing the two phases of solid and gas. Cokes added to the raw mix of which the amount is about 3.5% of the total weight was assumed to form a single particle with other components. In the early predition results presented in this paper, the flame propagation within the bed was not sustained after the top surface of the bed was ignited with hot gas. It suggests that the model should be extended to consider the multiple solid phase, which can treat the ore particles and the coke particles separately.

• 청정기술
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• 제8권1호
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• pp.11-17
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• 2002

Petcokes는 원유의 정제 과정에서 최종적으로 생산되는 부산물로 정제과정 중에 petcokes내에 무기물 및 황성분의 농축이 이루어진다. Petcokes는 각각의 분야에서 요구하는 품위에 적합해야 활용이 가능하다. 현재 국내에서 생산되는 petcokes는 황함량이 평균 6% 정도로 높아서 그대로 사용하기가 어렵다. 본 연구에서는 마이크로웨이브 가열을 이용하여 petcokes로부터 황을 제거하는 연구를 수행하였다. 지금까지 연구된 탈황방법에는 열 탈황, 수첨 탈황, 용매 추출에 의한 탈황, 그리고 알칼리 금속을 이용한 탈황 등이 있다. 본 연구에서는 새로운 방법인 마이크로웨이브 가열을 이용하여 petcokes로부터 탈황을 하고자 하였다. 실험은 마이크로웨이브만으로 가열하여 탈황하는 방법과 탈황율을 높이기 위해서 수소가스를 첨가하는 탈황을 수행하였다. 마이크로웨이브만으로 가열한 경우 1835W에서 2시간을 실험한 결과 68.3%의 탈황율을 보였다. 마이크로웨이브로 가열하며 수소를 첨가한 경우 1835W에서 1.5시간을 실험한 결과 86.4%의 탈황율을 얻을 수 있었다. 탈황 시간을 늘리거나 사용한 시료의 입자 크기가 줄여 준다면 더욱 높은 탈황율을 얻을 것으로 생각된다.

• 한국건설순환자원학회논문집
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• 제7권1호
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• pp.37-43
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• 2019

본 연구에서는 각종 산업부산물(플라이애시 2종, 페트로 코크스 연소 유동층 보일러 애시 및 고로 슬래그 미분말)을 활용한 싱크홀 복구용 경량 충전재 제조에 관한 연구를 수행하였다. 이를 위해 혼합물 실험계획법을 적용하여 산업부산물의 배합비에 따른 혼합 원료 물성(압축강도) 거동을 검토하였고, 상용프로그램인 MINITAB을 사용하여 통계적 분석을 하였다. 산업부산물의 배합조건별 압축강도는 고로 슬래그 미분말에 강한 의존성을 나타냈으며, 압축강도(3일 재령)는 고로 슬래그 미분말 사용량에 3~11MPa 수준이며, 유동층 보일러 플라이애시의 사용은 압축강도 발현에 미치는 영향이 가장 적은 것으로 평가되었다. 그리고 혼합물 실험계획에 따른 원료 배치 1조건에 대해서 기포 콘크리트를 제조하여 압축강도와 투수계수를 측정하였으며, 이때 부피비중 0.9~1.0, 겉보기 기공률은 30~50% 수준, 압축강도(3일 재령)는 1~2MPa 수준, 투수계수는 $10^{-2}{\sim}10^{-3}cm/sec$ 수준이다.