• 한국연소학회:학술대회논문집
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• 2006.10a
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• pp.293-298
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• 2006

There are many researches in progress on co-firing of coal and biomass to reduce carbon dioxide produced from the coal consumption. This study carried out 200 Kg/h combustion test furnace by mixing coal with timber. Coal was mixed with domestic and imported-wood around 10% to 20% based on input energy. For the mixed fuel, combustion temperature, unburned carbon and the composition of flue gas were analyzed. In addition, the tendency of slagging and fouling was examined using a probe. According to the result of the experiment, combustion temperature was depended on the kind of wood and mixing ratio. The unburned carbon loss was higher with increase of wood biomass mixing ratio, as a result, the total heat loss of furnace was slightly increased. The emission of NOx and SOx were decreased by $3{\sim}20%$ and $21{\sim}60%$ respectively. There are no difference of slagging and fouling tendency between biomass co-firing and coal burning only.

• Journal of the Korean Ceramic Society
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• v.32 no.4
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• pp.413-418
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• 1995

The (B.Si)C composite was prepared form the mixture of metal boron, silicon, and carbon powders in Ar atmosphere by Self-propagating High-temperature Synthesis Chemical Furnace. The characterization of synthesized power and sintered body were investigated. The microstructure of sintered body suggested that SiC boundary was made between B4C grains. The most excellent mechanical properties, the relative density of 95% oftheoretical value, 3 point flexural strength of 360MPa, and fracture toughness of 3.6MN/m3/2 could be obtained in 80wt% B4C-20 wt% SiC composite were obtained.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.11a
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• pp.687-690
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• 2005

Recently, to consider financial and constructive aspect, usage of Admixture, like Blast- Furnace Slag and Fly-Ash, are increased. These mineral admixtures, a by-product of steel industry, have many advantage, to reduce the heat of hydration, increase in ultimate strength, improve workability and etc. But it also reduces early-age strength, so it is prevented from using of Blast-Furnace Slag at cold-weather-concrete. In this study, for the purpose of increasing usage of mineral admixtures, like Blast-Furnace Slag and Fly ash, it is investigated the strength properties of concrete subjected to under low temperature According to this study, if early curing is carried out before having frost damage, the strength of concrete, subjected to frost damage, is recovered. And to consider increasing effect of strength, it is more effective to use of mineral admixtures, especially to use blast furance slag.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.29 no.11 s.242
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• pp.1257-1264
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• 2005

An inverse problem to determine two-dimensional total heat exchange factor is studied for the prediction of the slab temperature in the reheating furnace. Temperature measurements by the experiment are used in the inverse analysis. This inverse analysis employs the conjugate gradient method. The overall heat absorptances for 12-zones of the cross-section of the slab are estimated. The estimated temperatures at measurement locations are in good agreements with the measured temperatures.

• Journal of The Korean Society of Agricultural Engineers
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• v.55 no.3
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• pp.123-128
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• 2013

This study was performed to evaluate the slump flow, air content, setting time, compressive strength, adiabatic temperature rise and diffusion coefficient of chloride used ordinary portland cement, crushed coarse aggregate, crushed sand, river sand, fly ash, limestone powder, blast furnace slag powder and superplasticizer to find optimum mix design of low carbon green concrete for structures. The performances of low carbon green concrete used fly ash, limestone powder and blast furnace slag powder were remarkably improved. This fact is expected to have economical effects in the manufacture of low carbon green concrete for structures. Accordingly, the fly ash, limestone powder and blast furnace slag powder can be used for low carbon green concrete material.

• Journal of the Korean Ceramic Society
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• v.32 no.11
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• pp.1246-1254
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• 1995

A numerical model for fabrication and deposition of ultrafine SiO2 particles were proposed in the simplified horizontal MCVD apparatus using tube furnace reactor. The model equations such as energy and mass balance equations and the 0th, 1st and 2nd moment balance equations of aerosols were considered in the reactor. The phenomena of SiCl4 chemical reaction, SiO2 particle formation and coagulation, diffusion and thermophoresis of SiO2 particles were included in the aerosol dynamic equation. The profiles of gas temperature, SiCl4 concentration and SiO2 particle volume were calculated for standard conditions. The concentrations, sizes and deposition efficiencies of SiO2 particles were calculated, changing the process conditions such as tube furnace setting temperature, total gas flow rate and inlet SiCl4 concentration.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.29 no.1
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• pp.151-154
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• 2006

The high degree of viscosity and the non-Newtonian fluid dynamics characterizes the process inside a glass furnace. Because the temperature is fluctuating in very short time-intervals, it is hard to determine that the status of its fluctuation is stable or unstable. Usually Shewhart-chart is used to determine the control status. However because of the characteristics of the temperature fluctuations in the glass furnace it does not directly serve the purpose here. Therefore we suggest using ARIMA to diagnose control status and confirm that the method using ARIMA can be a better tool than Shewhart-chart.

• Journal of the Korean Ceramic Society
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• v.30 no.8
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• pp.685-693
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• 1993

Boron cabride was prepared from the mixture of metal boron and graphite powders in Argon atmosphere by Self-propagating High-temperature Synthesis Chemical furnace. The most excellent mechanical properties were in the case that Fe was added as a sintering agent before the synthesis of the B4C in the Chemical furnace. Sintered B4C-5wt% Fe specimen showed the relative density of 95%, of theoretical value, and 3-point-flexural strength of 380MPa.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.11a
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• pp.817-820
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• 2006

This study investigated on the differentiation of microstructure of blast furnace slag concrete(BBSC) using Mercury Intrusion Porosimetry(MIP). From the test result, it was found that the BBSC did not show shortcomings of high temperature curing. The BBSC gives more fineness microstructure than that of plain concrete when it is cured same curing condition. The curing age making stable structure to poor surroundings was 28, 14, 7 days for blast furnace concrete cured at 5, 20, $30^{\circ}C$, respectively.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2017.11a
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• pp.167-168
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• 2017

In this research, the blast-furnace slag powder using the hydrometer also attempted to analysis the influence factor due to the temperature change of water and sample, and the number of upside down turns at the time of rapid evaluation. As a result, the influence of the number of turn was not large, but was the temperature of the water and sample are greatly affected.