• 한국연소학회지
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• 제8권2호
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• pp.34-40
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• 2003

Analyses for concentration, surface phenomena, and crystal structure were performed to identify the causes of clinker formation in three type of pulverized coal fired boilers. Some clinkers had partially molten surface and more CaO and $Fe_2O_3$ as compared with fly ash, and the major crystalline phases identified in the clinker were mullite and quartz. Clinkers were formed in high temperature zone of the boiler according to the identification of mullite by XRD. Free $SiO_2$ in sand combined with K, Na and Ca in limestone served as a fluxing agent to form clinkers in a circulating bed boiler.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 추계학술대회논문집B
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• pp.705-710
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• 2001

The commercial viability of heat exchanger is mainly dependent on their long-term fouling characteristics because the fouling increases the pressure loss and degrades the thermal performance of a heat exchanger. An experimental study was performed to investigate the characteristics of fluid flow in a fluidized bed heat exchanger with circulating various solid particles. The present work showed that the drag force coefficients of particles in the internal flow were higher than in the external flow, in addition, they were lower with the shapes of particles being closer to the spherical geometries.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2005년도 동계학술발표대회 논문집
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• pp.288-293
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• 2005

The pressure distribution and heat transfer coefficient were measured at room temperature in the high suspension density CFB heat exchanger with multiple vertical tubes and the effective density of CFB was determined. The theoretical model for predicting heat transfer coefficient was developed in this study. The model predictions were compared with the measured heat transfer coefficient to show relatively good agreement between them.

• 설비공학논문집
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• 제19권3호
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• pp.263-268
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• 2007

The pressure drop and heat transfer coefficient were measured at room temperature in a CFB heat exchanger with multiple vertical tubes. The circulation rate of solid particles was also measured. The theoretical model for predicting heat transfer coefficient using the solid flowrate was developed in this study. The model predictions were compared with the measured heat transfer coefficient to show relatively good agreement.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2006년도 하계학술발표대회 논문집
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• pp.755-760
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• 2006

The exhaust gas with solid particle goes through the riser in both particle circulating type and circulating fluidized bed type heat exchanger to recover the heat. During heat transfer, gas velocity in vertical riser decreases as viscosity of exhaust gas decreases. In this case, when the particle size is fixed, sometimes the exhaust gas happens to have lower velocity which prohibit them to go out of the riser. In this paper the particle motion in vertical Rayleigh flow was studied. The behavior of heat transfer was investigated by means of velocity and temperature distribution. The result from numerical analysis was validated by the experimental results. Fortran code was used to analyze the particle motion in vertical Rayleigh flow.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2019년도 추계 학술논문 발표대회
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• pp.135-136
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• 2019

Recently, as the interest in environmental issues increases, the construction industry needs to recycle blast furnace slag, circulating fluidized bed Combustion fly ash, etc. to solve industrial by-products, and to develop artificial stone. In this study, the strength characteristics based on blast furnace slag according to the addition rate of alkali stimulant NaOH are investigated. The experimental results showed that the flexural and compressive strengths increased with the addition of alkali stimulants. Based on these results, it will be presented as a basic research data for the manufacture of artificial stone and will be tested later.

• 대한설비공학회지:설비저널
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• 제7권1호
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• pp.13-19
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• 1978

An experiment has been performed of find a temperature distribution of the circulating fluid in a packed bed thermal storage system when the inlet fluid temperature is constant. The thermal storage system is a specific-heat type in which the circulating fluid, hot air, exchanges heat directly with the heat storage materials, glass balls, in a heat storage bin. An empirical equation which includes two dimensionless variables $t^*\;and\;T_f^*$, is obtained. Also, heat storage efficiency and heat storage capacity are calculated from this equation, The heat transfer coefficient calculated by the suggested equation was compared with the value determined by the existing empirical equation.

• 한국환경과학회지
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• 제15권6호
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• pp.587-592
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• 2006

The advantage of CFBC(Circulating fluidized bed combustor) is that it can apply to various fuel sources including the lower rank fuel and remove SOx by means of direct supply of limestone to the combustor without additional desulfation facility. In this paper, we denote characteristics of fly and bed ash to reuse finer limestone usually abandoned(used spec[Coarse LS] 0.1mm under 25%, new spec[Fine LS] 0.1mm under 50%). According to the results, the chemical composition of fly ash was as follows; $SiO_2\;40.8%,\;Al_2O_3\;31.9%,\;CaO\;10.7%,\;K_2O\;4.46%$ in the case of coarse limestone and $SiO_2\;41.1%,\;Al_2O_3\;31.3%,\;CaO\;10.9%,\;K_2O\;4.66%$ in the case of fine limestone. The chemical composition of bed ash was as follows; $SiO_2\;54.2%,\;Al_2O_3\;33.1%,\;CaO\;1.56%,\;K_2O\;4.34%$ in the case of coarse limestone and $SiO_2\;53.8%,\;Al_2O_3\;32.6%,\;CaO\;2.21%,\;K_2O\;4.45%$ in the case of fine limestone. It showed that there was no significant change in chemical composition. And it is conformed that there was no significant change in particle size and shapes.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2014년도 제49회 KOSCO SYMPOSIUM 초록집
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• pp.55-57
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• 2014

• 한국건설순환자원학회지
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• 제9권3호
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• pp.8-12
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• 2014