• Journal of the Korean Society of Safety
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• v.25 no.1
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• pp.32-37
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• 2010

When back-out & firing Process applies heat, hume is piled up in exhaust duct by organic compound and it have high dangerousness. There by, the process is happening a lot of damage that is exhaust duct fire. However we do not have certain fire dangerousness estimation and digestion countermeasure. So we need preventive measure. Back-out & firing is a process which has fine structure, electrical and mechanical characteristics, such as firing kiln and back-out kiln which has pipe line and box type. The box oven is made of heating coil, fan motor and control panel. Back-out & firing process has air circulation institution of quick ventilation type. When we operate this process for long time, fire can break out easily. Duct is made by zinc shredder. If fire breaks out in duct inside, fire by deposit fume can be dispersed easily. Accordinglym, This project estimate danger for back-out & firing process exhaust duct through real fire test. And there is purpose of study to establish preventive measure.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.25 no.3
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• pp.236-240
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• 2012

Limiting thermal exposure time using rapid thermal processing(RTP) has emerged as promising simplified process for manufacturing of solar cell in a continuous way. This paper reports the simplification of co-firing using RTP. Actual temperature profile for co-firing after screen printing is a key issue for high-quality metal-semiconductor contact. The plateau time during the firing process were varied at $450^{\circ}C$ for 10~16 sec. Glass frit in Ag paste etch anti-reflection layer with plateau time. Glass frit in Ag paste is important for the Ag/Si contact formation and performances of crystalline Si solar cell. We achieved 17.14% efficiency with optimum conditions.

• Journal of Convergence for Information Technology
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• v.10 no.2
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• pp.82-88
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• 2020

The purpose of this study is to obtain basic data on the optimization of firing process conditions for enamel coating in chemical heat exchanger. The method of increasing the firing temperature in order to apply enamel coating to shell & tube type heat exchanger was examined. The temperature distribution of the heat exchanger in the firing kiln was numerically calculated using a commercial CFD program. The structural safety of the heat exchanger was confirmed by thermal stress analysis using the FSI method. Numerical analysis and experimental results show that there is a problem of safety due to temperature difference when the heat exchanger at room temperature is directly put into a firing kiln at 860℃. Therefore, a preheating process is need to reduce the temperature difference. As in Case2 with fewer firing steps, the first stage preheating temperature of 445℃and the second stage firing temperature of 860 ℃are considered to be most suitable.

• Current Photovoltaic Research
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• v.4 no.1
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• pp.12-15
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• 2016

Screen printing technique followed by firing has commonly been used as metallization for both laboratory and industrial based solar cells. In the solar cell industry, the firing process is usually conducted in a belt furnace and needs to be optimized for fabricating high efficiency solar cells. The printed-Al layer on the silicon is rapidly heated at over $800^{\circ}C$ which forms a layer of back surface field (BSF) between Si-Al interfaces. The BSF layer forms $p-p^+$ structure on the rear side of cells and lower rear surface recombination velocity (SRV). To have low SRV, deep $p^+$ layer and uniform junction formation are required. In this experiment, firing process was carried out by using conventional tube furnace with $N_2$ gas atmosphere to optimize $V_{oc}$ of laboratory cells. To measure the thickness of BSF layer, selective etching was conducted by using a solution composed of hydrogen fluoride, nitric acid and acetic acid. The $V_{oc}$ and pseudo efficiency were measured by Suns-$V_{oc}$ to compare cell properties with varied firing condition.

• Korean Journal of Materials Research
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• v.25 no.7
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• pp.336-340
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• 2015

For rear metallization with Al paste, Al back contacts require good passivation, high reflectance, and a processing temperature window compatible with the front metal. In this paper, the effect of the firing ambient during the metallization process on the formation of Al rear metal was investigated. We chose three different gases as ambient gases during the firing process. Using SEM, we observed the formation of a back surface field in $N_2$, $O_2$, and Air ambients. To determine the effect of the ambient on Voc, the suns-Voc tool was used. In this study, we described the mechanism of burn-out of organic materials in Al paste during the firing process. The oxygen ambient plays an important role in the burn-out process. We calculated the efficiency with obtained the back surface recombination velocities using PC1D simulation. It was found that the presence of oxygen during the firing process influenced the uniform back surface field because the organic materials in the Al paste were efficiently burned out during heating. The optimized temperature with oxygen flow shows an absolute efficiency of 19.1% at PC1D simulation.

• Journal of the Korean Society of Combustion
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• v.19 no.3
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• pp.8-17
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• 2014

The aims of this research were to evaluate effects of biomass co-firing to pulverized coal power plants and the variation of co-firing ratios on the plant efficiency related to power consumption of auxiliary system and flue gas characteristics such as production and component by process simulation based on the existing pulverized coal power plant. In this study, four kinds of biomass are selected as renewable fuel candidates for co-firing: wood pellet(WP), palm kernel shell(PKS), empty fruit bunch(EFB) and walnut shell(WS). Process simulation for various biomass fuels and co-firing ratios was performed using a commercial software. Gas side including combustion system and flue gas treatment system was considering with combination of water and steam side which contains turbines, condenser, feed water heaters and pumps. As a result, walnut shell might be the most suitable as co-firing fuel among four biomass since when 10% of walnut shell was co-fired with 90% of coal on thermal basis, flue gas production and power consumption of auxiliary systems were the smallest than those of other biomass co-firing while net plant efficiency was relatively higher than those of other biomass co-firing. However, with increasing walnut shell co-firing ratios, boiler efficiency and net plant efficiency were expected to decrease rather than coal combustion without biomass co-firing.

• The Journal of Advanced Prosthodontics
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• v.6 no.3
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• pp.177-184
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• 2014

PURPOSE. The aim of this study was to measure the changes on the marginal and internal adaptation of zirconia based anterior fixed partial dentures after the porcelain firing process. MATERIALS AND METHODS. A total of 34 anterior fixed partial dentures using LAVA CAD/CAM system (3M ESPE, Germany) were applied. Two silicone replicas were obtained: one is obtained before porcelain firing process (initial) and the other is obtained after porcelain firing process (final), followed by the examination under a binocular stereomicroscope. Kruskal Wallis and Wilcoxon Signed Ranks tests were used for the statistical analysis (P<.05). RESULTS. No statistically significant difference was found between initial and final marginal gap values (P>.05). At the internal gap measurements, final marginal area values ($59.54{\mu}m$) were significantly lower than the initial marginal area values ($68.68{\mu}m$)(P<.05). The highest and the lowest internal gap values were observed at the incisal/occlusal area and at the marginal area, respectively. In addition, lower internal gap values were obtained for canines than for central incisors, lateral incisors and premolars at the incisal area (P<.05). CONCLUSION. The firing cycles did not affect the marginal gap of Lava CAD/CAM system, but it is controversial for the internal gap.

• Journal of the Korean Society of Combustion
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• v.23 no.1
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• pp.44-54
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• 2018

Heat and mass balance process modeling has been conducted for a coal-firing power plant to be used as a testbed facility for development of various plant systems and equipment. As the material and design of the boiler tube bundle and fuel conversion to the biomass have become major concerns, the process modeling is required to incorporate those features in its calculation. The simulation cases for two different generation load show the satisfying results compared to the operational data from the actual system. Based on the established process conditions, the hypothetical case using wood pellet has also been simulated. Additional calculations for the tube bundle has been conducted regarding the changes in the tube material and design.

• 한국정보디스플레이학회:학술대회논문집
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• 2000.01a
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• pp.187-188
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• 2000

The conventional firing process method for the transparent dielectric layer in PDP Technology has disadvantages of low through put, high power consumption and large process area. We propose the rapid thermal scinterring (RTS) method as new process method to overcome these disadvantage characteristics. As the experimental result of this method, the optic transmittance(wavelength : 600nm) rate of transparent dielectric layer was more improved than conventional furnaces under the optimized gas supplying. Further, it was certified this method had the best conditions on the firing process of the PDP transparent dielectric layer.

• Korean Journal of Materials Research
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• v.24 no.8
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• pp.407-412
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• 2014

Currently, diopside ($MgCaSi_2O_6$) crystal glaze is used frequently for pottery works or in earthen wares, though the process is not straightforward. However, to create and control the positions and sizes of the crystals in desired amounts when making pottery is difficult. To solve this problem, a diopside crystal seed was created at a temperature of $1450^{\circ}C$. After planting this seed in the glaze, a glaze combination and firing process which allows a user to create crystals with the desired position and at the desired size were established. In addition, in order to investigate the creation process of the crystals, the growth patterns of the crystals were observed and examined using Raman spectrography and XRD and SEM analyses. As a result, the optimum synthesis condition of the diopside seed was created by mixing 1 mole of $CaCo_3$, 0.2 mole of $(MgCo_3)_4(MgCoH)_2{\cdot}5H_2O$ and 2 moles of $SiO_2$ and then applying a firing process to the mixture at $1,450^{\circ}C$ for 30 minutes. The optimum glaze content of the seed was 70 % feldspar, 20 % limestone and 10 % $MgCo_3$. For the firing process, it was confirmed that the size of crystal is larger with a longer firing time at $1100^{\circ}C$ by completing a two-hour process at $1280^{\circ}C$. In addition, the diopside crystal has columnar structure and is less than $1{\mu}m$ in size.