• 대한화학회지
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• 제56권4호
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• pp.431-439
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• 2012

Dissipative particle dynamics (DPD) was carried out to study the nucleation and crystal growth process of $CeO_2$ nanoparticles in different alcohol aqueous solutions. The results showed that the nucleation and crystal growth process of $CeO_2$ can be classified into three stages: nuclei growth, crystal stabilization and crystal aggregation except the initial induction stage, which could be reproduced by collecting simulation results after different simulation time. Properly selecting the sizes of $CeO_2$ and water bead was crucial in the simulation system. The influence of alcohol type and content in solutions, and precipitation temperature on the particle dimension were investigated in detail and compared with the experimental results. The consistency between simulation results and experimental data verify that the simulation can reproduce the macroscopic particle aggregation process. The effect of solvent on the nucleation and crystal growth of $CeO_2$ nanoparticles are different at three stages and can not be simply described by Derjaguin-Landau-Verwey-Overbeek (DLVO) theory or nucleation thermodynamics theory. Our work demonstrated that DPD methods can be applied to study nanoparticle forming process.

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 1997년도 International Symposium on Fire Science and Technology
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• pp.244-251
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• 1997

Since 1970s, The Petrochemical Industry in Korea has grown rapidly by the successful economic growth. While the process became larger and more complex, hazardous chemicals have been used in large quantity, Therefore, the risk of a major accident such as fire, explosion and toxic material release has been increased. Korea has been ranked the fifth in petrochemical product capacity worldwide, also required to meet international standards on process safety management. Fire Protection System integral part of safely management in Petrochemical Plants, will be reviewed.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 추계학술대회 논문집 Vol.19
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• pp.66-66
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• 2006

Development of ArF Photo-lithography process has proceeded with the increase of numerical aperature (NA) and the decrease of resist thickness. It makes many problems such as cost and process complexity. A novel spin-on hard mask system is proposed to overcome many problems Spin-on hard mask composed of two layers of siloxane and carbon. The optical thickness of two layers is designed from reflectivity measurement at specified n, k respectively. The property of photo-resist shows different results according to Si contents. Si-contents was measured XPS(X-ray Photoelectron spectroscopy).

• 대한기계학회논문집B
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• 제26권11호
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• pp.1578-1584
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• 2002

Combustion stability is one of the most important factors that must be considered in burning of heavy fuel oil, especially low-grade oil. This paper describes the combustion characteristics of petrochemical process by- product in the combustion furnace of heavy fuel oil. Main experimental parameters were combustion load, excess 02, fuel preheating temperature and air/fuel ratio. The capacity of CRF(combustion research facility) used in this study was 1.0 ton/hr and the burner is steam jet type suitable far heavy oil combustion and manufactured by UNIGAS in Italy. The fuel used in this experiment were 0.5 B-C, petrochemical process by-product and 3 kinds of 0.5 B-C/process by-product mixtures. The combustion stability was monitored and exhaust gases such as CO, NOx, SOx and particulates were measured with the excess $O_2$ and combustion load. The main purpose of this study is to clarify whether process by-product can be used as a boiler fuel or not in consideration of flame stability and emission properties.

• Safety and Health at Work
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• 제9권1호
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• pp.95-100
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• 2018

Background: Respiratory protection equipment (RPE) is the last resort to control exposure to workplace air pollutants. A comprehensive respiratory protection program (RPP) ensures that RPE is selected, used, and cared properly. Therefore, RPP must be well integrated into the occupational health and safety requirements. In this study, we evaluated the implementation of RPP in Iranian petrochemical industries to identify the required solutions to improve the current status of respiratory protection. Methods: This cross-sectional study was conducted among 24 petrochemical industries in Iran. The survey instrument was a checklist extracted from the Occupational Safety and Health Administration respiratory protection standard. An index, Respiratory Protection Program Index (RPPI), was developed and weighted by analytic hierarchy process to determine the compliance rate (CR) of provided respiratory protection measures with the RPP standard. Data analysis was performed using Excel 2010. Results: The most important element of RPP, according to experts, was respiratory hazard evaluation. The average value of RPPI in the petrochemical plants was $49{\pm}15%$. The highest and lowest of CR among RPP elements were RPE selection and medical evaluation, respectively. Conclusion: None of studied petrochemical industries implemented RPP completely. This can lead to employees' overexposure to hazardous workplace air contaminants. Increasing awareness of employees and employers through training is suggested by this study to improve such conditions.

• 한국화재소방학회논문지
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• 제26권1호
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• pp.38-42
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• 2012

울산, 여수 등 대단위 석유화학공장이 가동 중인 국가산업단지에서 화재 폭발 및 누출 등 중대산업사고가 발생되는 주요 원인과 안전관리 실태 등 문제점을 분석하여 이에 대한 제도적 측면 및 안전관리 측면에서 합리적인 대책을 제시해 보고자 한다.

• 한국안전학회지
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• 제18권3호
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• pp.75-80
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• 2003

This paper presents a set of typical pseudo-accident scenarios related to major equipments in petrochemical plants, which would be useful for performing such quantitative risk analysis techniques as fault tree analysis, event tree analysis, etc. These typical scenarios address what the main hazard of each equipment might be and how the accident might develop from an "initiating event". The proposed set of accident scenarios consists of total thirteen (13) scenarios specific for five (5) major equipments like reactor, distillation column, etc., and has been determined and screened out of one hundred and twenty-five (125) potential accident scenarios that were generated by performing semi-quantitative risk analysis practically for twenty-five (25) petrochemical processes, considering advices from the operation experts. It is assumed that with simple consideration or incorporation of plant-specific conditions only, the proposed accident scenarios could be easily reorganized or adapted for the relevant process with less time and labor by the safety engineers concerned in the petrochemical industries.ndustries.

• 경영과학
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• 제34권3호
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• pp.1-14
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• 2017

This study empirically analyzes the impact of inventory management performance on the energy efficiency in Korean petrochemical companies. The concept of the distance function is used to define the energy efficiency and the estimation of the distance function is performed using the stochastic frontier analysis. The inventory turnover is selected as the variable indicating the inventory management performance of the company. The main results of this study are as follows. First, the inventory turnover has a positive impact on energy efficiency. Second, during the period over 2011~2015, while the gap in energy efficiency among the companies expanded, the average energy efficiency decreased. Third, the average energy efficiency in upstream process companies was greater than downstream process companies and the gap in energy efficiency among downstream process companies was greater than upstream process companies. Fourth, the average marginal effect of inventory turnover on energy efficiency increased gradually from 2011 to 2015. Finally, the average marginal effect of inventory turnover in downstream process companies was greater than upstream process companies, and the gap in the marginal effect of inventory turnover among downstream process companies was greater than upstream process companies. These results together imply the importance of inventory management in terms of energy efficiency.

• 멤브레인
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• 제17권1호
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• pp.1-13
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• 2007

분리막을 이용한 투과증발공정은 에너지 소모가 적고 설치비와 운영비면에서 우수한 효과를 볼 수 있기 때문에 증류공정을 대신할 수 있는 공정으로 주목받고 있다. 특히 석유화학공정은 공정 중에 에너지 소모가 크고, 많은 화합물들이 공비혼합물을 이루고, 새로운 공정을 설치하기 위해서는 작은 공간을 필요로 하기 때문에 투과증발공정은 증류공정을 대체할 수 있는 매우 유력한 후보이다. 벤젠/시클로헥산을 포함하는 방향족 화합물의 분리, 올레핀/파라핀 분리, 자일렌 이성질체의 분리, 반응성 단량체의 회수, 가솔린으로부터 황 화합물의 제거 등에 투과증발공정을 응용하는 많은 연구가 이루어졌으며, 상용화가 되고 있다.

• 대한화학회지
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• 제57권1호
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• pp.25-34
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• 2013

The efficiency of three complex surfactants based on sunflower oil and nitrogen containing compounds as corrosion inhibitors for mild steel in $CO_2$-saturated 1% NaCl solution, has been determined by weight loss and LPR corrosion rate measurements. These compounds inhibit corrosion even at very low concentrations. The inhibition process was attributed to the formation of an adsorbed film on the metal surface that protects the metal against corrosive media. The inhibition efficiency increases with increasing the concentration of the studied inhibitors. Maximum inhibition efficiency of the surfactants is observed at concentrations around its critical micellar concentration (CMC). Adsorption of complex surfactants on the mild steel surface is in agreement with the Langmuir adsorption isotherm model, and the calculated Gibbs free energy values confirm the chemical nature of the adsorption. Energy dispersive X-ray fluorescence microscopy (EDRF) observations of the electrode surface confirmed the existence of such an adsorbed film.