• 한국결정성장학회지
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• 제18권6호
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• pp.258-263
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• 2008

입자를 부유 상태에서 소성할 수 있는 수직로를 이용하여 2 mm 이하 크기의 경량 세골재를 제조하고 그 물리적 특성을 고찰하였다. $1200{\sim}1300^{\circ}C$에서 소성된 대부분 시편은 표면에 다량의 액상이 발달하였고 따라서 내부의 가스가 팽창하여 다공성의 중앙부와 상대적으로 치밀한 표피층이 형성되었다. 특히 압출 성형체를 파쇄시켜 얻은 부정형의 C 계열 시편은 $1300^{\circ}C$ 이상으로 소결하면 내부에 가스가 팽창하여 시편 전체가 부풀어져서 구형으로 되었다. 본 부유 수직로에서 소성된 시편의 겉보기 비중은 $0.68{\sim}1.08$ 범위로 대부분 물에 뜰 정도의 경량이었다. 제조된 경량 세골재의 흡수율은 기공율과 비례하였고, 따라서 내부 기공들이 완전 고립된 폐쇄기공은 아님을 나타내었다. 부유소성로에서 제조된 세골재는 전기 머플로에서 소성된 시편과 비슷한 물성을 나타내었으나, 전기로에서 나타나는 골재 간 융착 현상이 발생하지 않았다. 수직로에서 부유소성된 세골재의 내충격성은 자연골재보다 다소 낮았으나, 단위용적중량은 KS 규격 기준을 만족하였다.

• 한국세라믹학회지
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• 제51권5호
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• pp.492-497
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• 2014

Artificial fine aggregates (denoted AFA) were fabricated using spent bleaching clay (denoted SBC) generated from processed vegetable oil and stone sludge (denoted SS) produced from crushed aggregate manufacturing materials for use as functional construction materials. Each raw material was crushed to particle size finer than $150{\mu}m$, and fine spherical pellets of approximately 1 ~ 4 mm in diameter were prepared by a pelletizing process. The physical properties of the AFA were measured with different types of sintering equipment. A new type of vertical furnace that sinters fine aggregates in a fluidized bed at high temperatures was designed and tested. AFA sintered in a rotary kiln at $1125^{\circ}C$ showed a bulk density of $1.5g/cm^3$ and a water absorption of 16%. AFA sintered in the vertical furnace at $1125^{\circ}C$ showed a bulk density of $1.9g/cm^3$ and water absorption of 8.5%. The bulk density of the AFA sintered in the vertical furnace showed a bulk density 27% higher and water absorption 47% lower than those of AFA sintered in the rotary kiln.

• 소성∙가공
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• 제20권2호
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• pp.132-139
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• 2011

Three dimensional simulations were performed for the deformation of a slab in a roller hearth type slab reheating furnace. The main objective of this study was to examine the deformation pattern of the slab due to the shadow effect, i.e., the temperature difference between the upper and lower slab surfaces, in particular, the variations of displacement and effective stress in the vertical direction. A commercially available FE code, ANSYS Workbench $12.1^{TM}$, was used in a fully coupled thermo-elasticity analysis. Several cases with different slab surface temperatures were selected for the simulations. For the sake of simplicity, the temperature environment inside the furnace was assumed to be homogeneous for the upper and lower faces of the slab. Two cases of with different slab width were selected as model geometry. The deformation patterns were computed and explained in terms of periodicity and symmetry. The results indicated that the shadow effect leads to a significant displacement in the vertical direction and, thereby, is one of the main reasons for the separation of the slab and its supports. These simulations also predicted that the deformation is more severe along the transverse direction than along the longitudinal direction.

• 한국진공학회지
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• 제19권5호
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• pp.377-384
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• 2010

본 연구에서는 수직 가열로(vertical furnace)를 이용하여 $1150^{\circ}C$의 온도에서 섬유형태의 고순도 단일벽 탄소나노튜브(singlewalled carbon nanotubes)를 합성하였다. 탄소나노튜브의 구조에 영향을 미치는 실험 변수인 페로센(ferrocene)의 농도, 혼합용액의 주입 속도, 싸이오펜(thiophene)의 농도, 수소($H_2$)의 주입 양을 조절하여 고순도의 단일벽 탄소나노튜브 섬유의 최적화 된 대량 합성 조건을 확립하였다. 또한 각 요인들이 탄소나노튜브의 생성에 미치는 영향에 대해 논의하였다. 분석 결과, 최적화 된 조건에서 1.16~1.64 nm의 직경을 가진 고순도의 단일벽 탄소나노튜브가 다발(bundle) 구조로 정렬되어 있음을 확인할 수 있었다.

• 한국연소학회:학술대회논문집
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• 한국연소학회 1998년도 제17회 KOSCI SYMPOSIUM 논문집
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• pp.79-84
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• 1998

In this paper we show design and operation of 1MWth pulverized coal combustion test facility. The test facility is consists of coal feeding system, furnace and flue gas treatment system. The furnace is equipped with a top-fired burner in order to avoid influence of gravity on the coal particles. There are two part of vertical(VP) and horizontal pass(HP) at furnace. We can measure temperature and species of coal flames in vertical pass. Also, there is horizontally arranged section where investigation regarding corrosion and deposit formation will be carried out. The burner of combustor was externally air staging burner(EASB) type made by IFRF. The pulverized high bituminous(Blair athol) coal from Australia was used as fuel, and the particle size less than 80 ${\mu}m$ was 83.4%. Overall excess air ratio was 1.2.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 춘계 학술발표회
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• pp.1006-1011
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• 2010

This study was focused on the reactivity of furnace slag against cadmium to design the vertical drain method with reactive column for improving contaminated sea shore sediment. The removal capacity of furnace slag was analyzed using pseudo-second-order model. And the effective parameters of removal test were initial concentration and initial pH. According to equilibrium removal amount and reactive constant calculated by pseudo-second-order model, the removal capacity was analyzed. Equilibrium removal amount of furnace slag was linearly increased as increasing intial cadmium concentration. Because the pH was around 11, the removal mechanism of furnace slag could be both sorption and precipitation. Therefore the removal amount was increased due to initial concentration. pH was increased to around 11 in the case of "No treat", but the pH were 3.8 in the case of "HAc added" and 0.7 in the case of "HCl added". The removal amount was different 4.8, 1.19 and 0.27 mg/g. This results show the pH was major factor to remove cadmium using furnace slag.

• 한국세라믹학회:학술대회논문집
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• 한국세라믹학회 2003년도 춘계총회 및 연구발표회 초록집
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• pp.161.1-161
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• 2003

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2011년도 추계학술발표대회 논문집
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• pp.74-79
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• 2011

Concentration characteristics of the KIER solar furnace are analyzed with a heat flux measurement technique. Total heat capacity of 40kW was confirmed within 1.04% average error, and the normalized maximum heat flux of 3,452 $kW/m^2$ was proved. Non-Gaussian flux distribution in the vertical direction implies that reflectors should not be random rather inclined downwards. Moreover, we characterized flux distribution variations with furnace blind opening ratio, distance from the focal plane, and misalignment of the measurement system. Based on the results, the heat flux distribution can be simply estimated once reflectivity and direct normal insolation values are known. This study will be helpful to the design and the performance evaluation of receivers or chemical reactors.

• 한국결정성장학회지
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• 제6권2호
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• pp.220-228
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• 1996

두 개의 siliconit 발열체를 써서 이단 전기로를 제작하여 수직 Bridgman법으로 CdTe 단결정을 성장시켰다. 상단전기로의 최고온부를 $1150^{\circ}C$로 고정시키고 하단전기로를 $800^{\circ}C$로 하였을 때, $22.51150^{\circ}C$/cm의 온도 기울기를 얻었다. 성장된 시료의 X$.$선 회절 실험으로부터 얻은 격자상수 $a_0$는 6.482$\AA$이었고, 실온에서 광흡수 측정으로부터 얻은 밴드갭 에너지는 1.478eV이었다. 광발광(PL) 실험으로부터, 구속된 엑시톤 방출 피크가 각각 ($A^0$, X) (1.5902, 1.5887ev), (h,$D^o$) (1.5918 eV) 그리고 ($D^o$, X) (1.5928, 1.5932 eV)의 방출 피크로 분리되는 것을 확인할 수 있었으며, 중성주개와 중성받개의 결합에너지와 이온화에너지를 계산하였다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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• pp.375-380
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• 2001

MF is a half shaft blast furnace which has been developed at Mitsui Miike Smelter in the 1960’s to treat vertical retort residue. The MF has also been tested for treatment of various recycling materials and wastes. Now various secondaries and wastes (EAF dust, zinc leaching residue, Cu sludge, etc ) are mainly treated. Powder materials are briquetted with reductant before being fed to the furnace. Products are crude zinc oxide, matte, non-hazardous slag and steam. Zinc and lead are recovered in oxide dust, and copper and silver are recovered in matte. The MF can be widely applied to many kinds of materials which contain such non-ferrous metal-valuables. In addition, the improvement in operation and technology has effectively made the unit capacity much larger. The MF now has many advantages for these treatment processes.