• Proceedings of the Korean Nuclear Society Conference
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• 1998.05b
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• pp.397-402
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• 1998

염소가스의 활성탄 흡착성능을 흡착평형과 flow system 두 단계의 흡착실험을 통하여 측정하였다. 활성탄은 surface area와 pore size distribution이 구별되는 세가지 이상의 시료를 선정하였고 활성탄의 표면특성에 따른 염소가스의 흡착관계를 검토하였다. Flow system에서는 염소가스를 500ppm의 농도(v/v in helium) 를 가지는 염소가스를 선택하였고 GC로 흡착경향을 분석하였다. 주어진 흡착탑(long bed)에서 흡착용량의 증가변화에 대한 흡착속도의 감소변화의 추이를 관찰하였으며 이로부터 염소가스 단일성분의 활성탄 흡착탑에 대한 흡착모델의 설계가 가능함을 알 수 있었다.

• Journal of the Korean Institute of Gas
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• v.8 no.1 s.22
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• pp.13-17
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• 2004

To evaluate suitability of the Gaussian plume model for the small scale release of a dense toxic gas, experimental concentrations of the small scale release of chlorine were compared with theoretical concentrations calculated by the Gaussian plume model using various dispersion coefficients. As a result, Ive found that the dispersion of chlorine gas was fairly varied with dispersion coefficient and atmospheric stability and that chlorine concentrations were well estimated by the Gaussian plume model using Briggs' dispersion coefficient and the effective release hight.

• Korean Journal of Materials Research
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• v.6 no.9
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• pp.919-924
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• 1996

사염화우라늄을 제조하기 위한 가장 효율적인 반응계는 이산화우라늄, 염소가스와 탄소분말이다. 여러 가지 실험변수 가운데 이산화우라늄의 염소화반응에 사용된 염소가스 주입량과 탄소의 양이 사염화우라늄 제조에 미치는 영향에 관하여 연구하였다. 각각의 실험변수들에 대한 전화율과 휘발률 계산을 통해 효율적인 반응을 위한 적정 염소가스 주입량과 탄소의 양을 구하였고, 이산화우라늄의 증가함에 따라 직접접촉에 의한 기체-고체반응에서는 전화율과 휘발률은 증가했으나 이후 과량을 첨가함에 따라 감소하였고, 용융염내의 기체-액체반응에서는 전화율의 미미한 증가와 휘발률의 감소를 확인하였가. 염소주입량이 증가함에 따라 전화율과 휘발률이 증가했으며, 과량의 염소가수 주입시 고이온가 염화물의 생성량이 증가하였다.

• Korean Journal of Materials Research
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• v.7 no.4
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• pp.317-321
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• 1997

사염화우라늄 제조를 위해 염소가스와 탄소를 이용한 이산화우라늄의 염소화반응에 대하여 연구하였다. 이론적측면에서 열화학적 자료를 이용한 계산을 통하여 일어날 수 있는 반응들을 확인하였으며, 염소화반응이 진행되는 동안 초래될 현상에 대하여 검토하였다. 실험결과로 부터 반응온도, 반응시간 및 질소가스 주입비율이 사염화우라늄 제조에 미치는 영향을 정량적으로 평가하였다. 순수한 이산화우라늄을 사용한 사염화우라늄 제조공정에서의 적절한 반응시간과 반응온도는 각각 약 2시간과 50$0^{\circ}C$-$700^{\circ}C$범위였으며, 질소가스의 적정 주입량은 염소가스의 약 50%로 나타났다.

• Resources Recycling
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• v.27 no.5
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• pp.54-60
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• 2018

The quality of steel produced from scrap can be adversely affected because of the buildup of tramp elements in recycled scrap. The tramp element of greatest concern is copper because of its effect on steel quality, even in small percentage quantities. In this study, possibility of removal of copper from ferrous scrap by using $Cl_2$ gas is experimentally examined in a small size experimental apparatus. Synthetic ferrous scraps containing copper were reacted with $Cl_2$ gas in various atmosphere. The copper was chloridized and evaporated, whereas iron was oxidized and was not reacted with Cl2 and oxygen mixture gas.

• Journal of the Korean Institute of Gas
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• v.8 no.2 s.23
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• pp.8-14
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• 2004

This study analyzed dispersion characteristics and toxic effect in the small-scale continuous release of chlorine gas. We found that the Gaussian model using the Briggs' dispersion coefficient and the effective release height was better predicting experiments than the BM model. From chlorine concentrations calculated by Gaussian model, simulation results showed that the dispersion of chlorine was more affected by atmospheric stability and wind speed than release rate and that the toxic effect of chlorine gas was similar to the effect of parameters on chlorine dispersion. From effected areas with toxic criteria, damaged areas could be estimated to protect human.

• Journal of Bio-Environment Control
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• v.28 no.2
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• pp.166-171
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• 2019

This study was conducted to investigate the effect of gaseous chlorine dioxide ($ClO_2$) concentration and treatment method for maintaining marketability in strawberries 'Maehyang' for export. After harvesting strawberry colored with $60{\pm}5%$ of the skin, and the gaseous $ClO_2$ was applied as four treatments in the cold store set with $10^{\circ}C$ which were as follows: i) non-treatment (Control), ii) $0.2mg{\cdot}L^{-1}$ for 30 minutes, iii) $0.4mg{\cdot}L^{-1}$ for 30 minutes, and iv) continuously exposed at $0.4mg{\cdot}L^{-1}$ during the storage period. Weight loss, firmness, soluble solids content, color, incidence of gray mold, and quality grade of strawberries were investigated every 3 days during 16 days storage in cold store. The weight loss was consistently high at $0.2mg{\cdot}L^{-1}\;ClO_2$ treatment, and the weight loss was lower than other treatments when gaseous $ClO_2$ was continuously treated. Firmness was significantly higher at 0.2 and $0.4mg{\cdot}L^{-1}$ $ClO_2$ treatment on the 13th day of storage. Soluble solids content tended to below in continuous gaseous $ClO_2$ treatment. The colors showed no tendency as affected by concentrations and treatment methods of gaseous $ClO_2$. No gray mold was observed in the continuous gaseous $ClO_2$ treatment until the 13th day of storage. The quality grade was lower in gaseous $ClO_2$ treatment group than in the control. As a result, it was possible to decrease the weight loss and the incidence of gray mold by continuously treating the gaseous $ClO_2$ to strawberry 'Maehyang' for export during the storage period after harvest. However, further research is needed on method to maintain quality grades of fruits.

• Journal of the Korean Institute of Gas
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• v.18 no.5
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• pp.1-5
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• 2014

As high-tech science has developed, the need of semiconductor is required constantly. However, there are many processes which use a great deal of poisonous gas in the semiconductor process, so the dangerousness by a gas leak is latent in these processes. Especially, the accident of toxic gas is almost made by ammonia and chlorine. Therefore this report estimates the damage by the leak of ammonia and chlorine used in LPCVD system.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.19 no.1
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• pp.17-27
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• 2013

The effects of chlorine dioxide gas ($ClO_2$) treatments between high-concentration-short-time and low-concentration-long-time on maintaining the quality of cherry tomatoes (Lycopersicon esculentum Mill. cv 'unicorn') were investigated. Tomatoes were treated with 5 ppm for 10 min and 10 ppm for 3 min as high-concentration-short-time $ClO_2$ gas treatment conditions and 1 ppm for once a day interval in terms of low-concentration-long-time $ClO_2$ gas treatment condition, respectively. After $ClO_2$ gas treatments, tomatoes were storage at 5 and $23^{\circ}C$ for 7 days. Weight loss, changes in tomato color, firmness, soluble solids content, pH, growth of total microorganism, and decay rate were evaluated. On day 7, tomatoes treated with chlorine dioxide gas showed low values of respiratory rate, total microbial growth, and decay rate compared to those of tomato without chlorine dioxide gas treatment. Additionally, tomatoes treated the chlorine dioxide were kept the values of firmness and soluble solids content during storage. However, chlorine dioxide gas treatment on tomatoes had no direct effect on weight loss, pH, and color. Results showed that both $ClO_2$ concentration and treatment time played the important roles for keeping the quality of tomatoes during storage. Tomatoes with chlorine dioxide gas treatment of low-concentration-long-time had more effective values of firmness, the total microbial growth, and decay rate than those with two chlorine dioxide gas treatments of high-concentration-short-time. Results suggest the potential use of chlorine dioxide gas treatment of low-concentration-long-time as an highly effective method for keeping the freshness of cherry tomato.

• Journal of Animal Environmental Science
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• v.18 no.sup
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• pp.1-6
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• 2012

This study was conducted to verify the effect of chlorine dioxide ($ClO_2$) on odor reduction at a commercial swine facility consisting of a compost ficility. Compost facility in $NH_3$ concentration was around 550 ppm and less than 78 ppm before and after the $ClO_2$ spraying, respectively, which was over 86% reduction. There was no H2S detection. $NH_3$ concentration was around 420 ppm and less than 35 ppm before and after the $ClO_2$ spraying, respectively, which was over 83% reduction. $H_2S$ concentration was around 210 ppb and less than 32 ppb before and after the $ClO_2$ spraying, respectively, which was over 85% reduction. Hence, $ClO_2$ spraying at windowless barns was compost facility decreased malodor such as $NH_3$.