• Journal of Korea Foundry Society
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• v.41 no.1
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• pp.16-25
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• 2021

The development of technology to prevent environmental pollutants and reduce energy consumption has already become a very significant issue not only for the foundry industry but also for society as a whole. In this paper, we introduce a new dust collector developed for low energy consumption and high performance compared to a roof top dust collector. The roof top dust collector which is using widely in the domestic foundry plant has a low performance about the dust suction ability in spite of high energy consumption because it is installed in a high place to collect the whole dust from all processes in foundry. A dust collector away from dust sources inevitably has low energy efficiency. The development of an efficient collector for foundry is very difficult because the position of the dust source continues to change from the melting process to the pouring process. New dust collector is installed on the ladle transfer equipment such as cranes, hoists, and monorails to effectively respond to moving dust sources. The movable device, attached close to the source of dust, provides high performance even with low energy consumption. The new dust collector is expected to be an environment-friendly device that can be applied to the foundry.

• Journal of Korea Foundry Society
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• v.10 no.4
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• pp.284-288
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• 1990

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.7 no.2
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• pp.196-208
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• 1997

This study was performed to estimate quartz contents in the both bulk and airborne dust samples and to determine particle size distribution of airborne dust from the selected foundry operations. Total dust samples were collected by a 37mm cassette and respirable by a 10 mm nylon cyclone. Particle size distributions were determined by a Marple's 8-stage cascade impactor at the melting, molding, shakeout and finishing operations. The presence of elements in the dust samples were confirmed by the scanning electron microscopy equipped with the energy dispersive x-ray spectrometry. The quartz contents were estimated using the intensity of the absorption peak of quartz at 799 cm-l by the Fourie Transformed Infrared Spectroscopy (FTIR). The results were as follows: 1. The analysis of data from cascade Impactor showed bimodal distributions of particle size at the melting, molding and shakeout operations. Mass median aerodynamic diameters for the distributions determined by histogram were $0.48-1.65{\mu}m$ for small and $13.43-19.58{\mu}m$ for large modes. In the dust samples collected at the finishing operations, however, only a large mode of $18.89{\mu}m$ was found. 2. The percentages of total to respirable dust concentration calculated from the impactor data ranged from 42 % to 66 %. The average concentrations of respirable dust by cyclone were $0.85-1.28mg/m^3$ collected from the workers, and were $0.23-0.56mg/m^3$ from the areas surveyed. Dust concentrations of personal samples were statistically significantly higher than those of area samples. The highest dust concentration was obtained from the personal samples of the finishing operation. 3. The mean percentages of silicon and oxygen estimated by SEM-EDXA in the bulk samples ranged from 35.83 % to 36.02 % and from 39.93 %-41.64 %, respectively. 4. The average quartz contents estimated by FTIR in the respirable dust from personal samples ranged from 4.32 % to 5.36 % and 4.54 % to 4.70 % in the bulk samples. No statistical difference of quartz content was found between foundry operations. In this study, quartz content was quantified by FTIR. Although no statistically significant difference in quartz content between airborne and bulk, samples and between different foundry operations was found, it is recommended that quartz content in the individual sample of respirable dust be analyzed and the results be used either to select an applicable quartz limits or to calculate the exposure limit. Further studies, however, are needed to compare the results by FTIR and XRD since it is reported that the quartz content determined by FTIR is different from that by XRD.

• Journal of Environmental Health Sciences
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• v.28 no.3
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• pp.64-71
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• 2002

Hair provides important information about the body's mineral status. Therefore, we have studied the trace elemental distribution in human hair under different inhalation and ingestion environment using neutron activation analysis (NAA). NAA is a powerful analytical method which can be used successfully to determine trace elements in environmental and biological materials. Total diet and six different herbal medicine were analysed to study ingestion environment. Airborne dust in foundry was analysed and compared with outdoor dust to study inhalation environment. Human hairs of common person, herbal medicine taker and foundry worker were analysed to estimate the trace elemental distribution of people under different inhalation and ingestion environment. Analytical results show that herbal medicines contain higher micronutrients such as Ca, Mg, Mn and Cu that total diet and airborne dust in foundry has high Cr. The concentration of Ca, Mg and Mn in hair of herbal medicine taker is two times higher than in hair of common person and Cr con-centration in hair of foundry worker is about three times higher than in hair of common person. These results show that NAA can be used importantly to monitor human health through biological and environmental samples.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.8 no.1
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• pp.50-66
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• 1998

This study was conducted to estimate crystalline silica contents in airborne respirable dust from various manufacturing industries and to compare analytical performance of two methods of quantifying crystalline silica, X-ray diffraction(XRD) and Fourie transform infrared spectroscopy (FTIR). For this study, various manufacturing industries with a history of having pneumoconiosis cases and also known to generate dusts containing crystalline silica were investigated. These industries include: foundry, brick, potteries, concrete, and abrasive material, etc. Both personal and area respirable dust samples were collected using 10 mm, Dorr-Oliver nylon cyclone equipped with 37mm, $5{\mu}m$ pore size, polyvinylchloride (PVC) filters as collection media. In addition, total dust samples were collected side-by-side to the respirable samples. All samples were weighed before and after sampling and were pretreated according to the NIOSH sampling and analytical methods 0500, 7500, and 7602 for dust collection and quartz analysis. In addition, bulk samples were collected and analyzed by X-ray fluorescence (XRF) for minerals. In this article, only the results obtained from foundry are reported. The results from various other industries will be published in future articles. The respirable dust concentrations from personal samples by cyclone were $0.46-1.06mg/m^3$ and those from area samples were $0.34-0.73mg/m^3$. Dust concentrations of personal samples were significantly higher than those of area samples. The highest dust concentration was obtained from the personal samples of the finishing operation. Total dust concentration ranged $1.24-3.40mg/m^3$. The mean quartz contents estimated by FTIR and XRD in the personal respirable dust samples were 5.12% and 4.41%, respectively, without significant difference between them. For quartz analyses, the two techniques were highly correlated with $r^2$ ranged 0.803-0.920. But the results by FTIR were mostly higher than those by XRD. In addition, cristobalite was not detected by FTIR. Significant correlations between contents of crystalline silica and such minerals as $Al_2O_3$, CaO, $TiO_2$, and $K_2O$ suggest possible interferences from these minerals.

• Journal of Korea Foundry Society
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• v.3 no.2
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• pp.100-105
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• 1983

The mechanism of coal-dust action on inhibiting burn-on of Sand to iron castings was taken in consideration by means of casting test and thermal decomposition test. To compare the ability of inhibiting sand burn-on, test castings were produced in green sand moulds added three different coal-rusts. And quantitative determination of lustrous carbon and volatiles production for coal-dust samples were performed.The lustrous carbon production was in good agreement with the casting test result. But total voltiles production was relatively inefficient on hibiting sand burn-on to test castings.The lustrous carbon theory can be given to explain the mechanism which coal-dust inhibits sand burn-on to iron castings.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.10a
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• pp.158-158
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• 2003

• Korean Chemical Engineering Research
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• v.44 no.2
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• pp.136-148
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• 2006

A foundry makes various machinery parts made by iron. For manufacturing machinery parts, they usually uses wooden mold with molding sand and pour the molten iron into wooden mold through inlet. A foundry have many processes including Furan process, In Furan process workers prepares a wooden mold in the molding sand. So they fixes wooden mold in sand housing and then they fill the molding sand in the sand housing. Molding sand should be sticky enough to sustain the shape of wooden mold, so several materials are needed to prepare the suitable molding sand. The first step of Furan process is making the molding sand with molding sand and Voltaic Organic Compounds (VOC) and the second step of Furan process is pour the molding sand into the wooden molding housing. This two step of process generated noxious VOC and various size of dust. So the process is very dirty and dangerous one. Because of these, Workers frequently shrink out of the plant. The company related with foundry usually faced on the difficult situation for engagement and always have shortage of hiring problem. Through this study, we developed a system which removes toxic VOC and dust simultaneously. We design and construct real system and install it at real plant. Before setting up this system, the working surroundings VOC (for formaldehyde) 15 ppm and Dust(for $PM_{10}$) $8,000{\mu}g/m^3$. After setting up this system, working surroundings is improved by VOC (for formaldehyde) 0 ppm, Dust(for $PM_{10}$) $4{\mu}g/m^3$, and the work evasion factor is removed. So we contribute to solve hiring problem of this company and increasing the productivity also.

• Journal of Korean Society for Atmospheric Environment
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• v.22 no.1
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• pp.35-41
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• 2006

The steel foundries with electric arc furnaces handling metal scraps have recently gained an attention as a potential source of dusts. The present study focuses on the analysis of dust emissions and removals during furnace charging and melting processes by commercial CFD software named FLUENT. A body fitted grid system consisting of 880,000 meshes was first generated by Gambit for the electric arc furnace with the capacity of 60 ton/cycle and then FLUENT was invoked to solve the corresponding NavierStokers equation for the momentum, temperature and dust concentration. The entire processes from metal charging to metal melting were simulated to investigate the unsteady behaviors of fluid flows and dust concentrations. The model simulation results showed that as the top of the electric arc furnace opened for metal charging, hot plumes bursted out from the furnace rose strongly by buoyance and escaped mostly through the main hood. Therefore, the capacity of main hoods determined the vent efficiency in the metal charging process. As the furnace was closed after the metal charging and the metal melting processes was followed, the hot flow stream stretching from the furnace to the main hood was dissipated fast and the flow from the inlet of the bottom of the left hand side to the main and monitoring hoods constituted the main stream. And there was only a slow flow in the right hand side of the furnace. Therefore, the dust concentrations were calculated higher in the left hand side of the furnace, which was consistent with observations.

• Journal of Preventive Medicine and Public Health
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• v.27 no.2 s.46
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• pp.274-285
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• 1994

The effects of resin on the respiratory health have been investigated in 309 workers from four iron and steel foundries and the results compared with those from 122 workers who were not significantly exposed to resin gas and silica dust at the same industries. Phenol-formaldehyde resin was used in the core making and molding processes and workers were exposed to their decomposition products as well as to silica dust containing particulates. The subjects were grouped according to formaldehyde, dust and other gas exposures, and smoking habits were considered also in thi analysis. Standardized respiratory symptom questionnaire was administered by trained interviewers. Chest radiograph, pulmonary funtion tests, and methacholine challenge tests were done. Environmental measurements at the breathing zone were carried out to determine levels of formaldehyde, respiable dust and total dust. Foundry workers had a higher prevalence of symptoms of chronic bronchitis with chronic phlegm and chronic cough when exposed to dust. Exposure to gas was significantly associated with lowered $FEV_1$ and obstructive pulmonary function changes. Exposure to formaldehyde and phenol gas was associated with wheezing symptom among workers, but $FEV_1$ changes after methacholine challenge were not significantly different among different exposure groups. When asthma was defined as the presence of bronchial hyperreactivity with more than 20% decrease in $FEV_1$ after methacholine challenge, 17 workers out of 222 tested had asthma. Fewer asthmatic welters were found among groups exposed to formaldehyde, gas and dust, which indicates a healthy worker effects ill a cross-sectional study. The concentration of formaldehyde gas ranged from 0.24 to 0.43 ppm among studied foundries. The authors conclude that formaldehyde and phenol gas from combusted resin is probably the cause of asthmatic symptoms and also a selection force of those with higher bronchial reactivity away from exposures.