• Korean Chemical Engineering Research
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• v.54 no.3
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• pp.340-349
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• 2016

Electro oxidation system was designed in this study for the reduction of COD (Chemical Oxygen Demand) from high-strength wastewater, produced during refinery turnaround period. First, BDD (Boron Doped Diamond) electrode was synthesized and electro oxidation system of actual industrial wastewater was developed by adopting the synthesized BDD electrode. The experiments were carried out under various operating conditions under certain range of current density, pH, electrolyte concentration and reaction time. Secondly, reaction kinetics were identified based on the experimental results, and the kinetics were embedded into a genetic mathematical model of the electro oxidation system. Lastly, design and operating parameters of the process were optimized to maximize the efficiency of the pretreatment system. The coefficient of determination ($R^2$) of the model was found to be 0.982, and it proved high accuracy of the model compared with experimental results.

• Journal of Environmental Health Sciences
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• v.24 no.3
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• pp.124-130
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• 1998

This study was to examine the utilization of waste egg snells for removal of heavy metals in laboratory wastewater. It was estimated that pH increasing formed heavy metals into a hydroxide and then settled to remove them. Removal rate of heavy metals were increased as increased dosage, low adsorbate concentration and passed reaction time. Average adsorption volumes of Cr, Cu, Mn and Pb per g were about 1.21 mg, 1.1 mg, 0.96 mg and 1.04 mg, respectively. If we reflected the adsorption capacity(k) and adsorption intensity(1/n) of Freundlich isotherm, we couldn't consider waste egg shells as a good adsorbent. It seemed that heavy metals contained in complex wastewater was removed to be influenced by inital pH, solubilities with passed reaction rime and competitive reaction.

• Journal of Korean Society of Water and Wastewater
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• v.24 no.4
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• pp.395-406
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• 2010

In this study, anaerobic digestion, electro-oxidation and electro-fenton oxidation processes were investigated to reduce oily refinery sludge. Anaerobic digestion process was not suitable for oily activated sludge reduction because of characteristics itself and, as experimental results revealed, reduction efficiency was low for electro-oxidation process. However, 40% total suspended solid reduction of oily activated sludge was obtained by electro-fenton oxidation process, operating at pH=1, 0.5 A and $Fe^{2+}$:$H_2O_2$ ratio = 1:30. In addition, higher reduction efficiency was obtained as reaction time was increased (30, 60, 90, 120 min) despite of low $H_2O_2$ concentration. From the results, it has been investigated that electro-fenton oxidation is efficient process for oily activated sludge reduction.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.11a
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• pp.349-350
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• 2003

악취의 배출원은 제지공장, 정유공장, 화학공장 등과 같이 다양한 산업시설과 축사, 음식물 처리시설, 하ㆍ폐수처리장, 분뇨처리장, 생활폐기물 매립장 등의 생활악취시설로 구분할 수 있다. 산업시설의 경우, 악취배출시설에 대한 감시와 관리가 강화되었으나, 생활악취 배출시설의 경우 생활 주변에 광범위하게 자리 잡고 있어 효율적인 악취관리가 이루어지고 있지 않다. 악취 민원이 사회적 문제가 되고 있는 생활폐기물 매립장의 경우 차폐시설을 설치할 수 없어, 지형적인 영향과 기상조건 및 시간에 따라 변화하는 악취의 발생 특성까지 고려해야 하므로 관리가 더욱 어렵다. (중략)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 1999.10a
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• pp.443-444
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• 1999

악취는 냄새를 유발하는 기체상 물질이 사람의 후각을 자극하여 불쾌감이나 혐오감을 주는 상태를 말한다. 악취물질은 정유공장, 화학공장, 하수처리장, 분뇨 및 축산 폐수처리장, 매립장 등의 다양한 발생원이 있으며, 여러가지 복합된 화합물이 원인이 되어 악취를 유발한다. 단위 물질로서 황화수소(H$_2$S)는 계란 썩는 냄새, 메르캅탄(mercaptan)류는 야채 썩는 냄새, 아민류는 생선냄새 등의 특이한 냄새를 유발하며, 최저 감지값은 물질별로 상당한 차이를 나타내고 있다(이광묵, 1993).(중략)

• Korean Journal of Environmental Agriculture
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• v.19 no.3
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• pp.194-200
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• 2000

The amount of swine wastewater reaches about $197,000m^3$ per day at live-stock houses in the whole country. A half of the swine wastewater resources are too small to be restricted legally. This untreated wastewater causes the eutrophication in the water bodies. In case of swine wastewater treatment, the solid-liquid separation must be performed because feces(solid phase) and urine(liquid phase) have large differences in nitrogen and phosphorus concentration. It is necessary to assess exactly the concentration of the pollutants in swine wastewater for planning the wastewater treatment facilities. A full-scale operation was carried out in K city and the plant is consists of conventional plant, the supplementary flocculation basin of chemical treatment process and $anaerobic{\cdot}aerobic$ basin for nitrogen removal. The improved full-scale swine wastewater treatment plant removed the $1,500{\sim}3,000mg/l$ of total-nitrogen(T-N) to 120mg/l of T-N and $131{\sim}156mg/l$ of total-phosphorus(T-P) to $0.15{\sim}1.00mg/l$ of T-N. Accordingly, as a results of operational improvement, the removal efficiencies of T-N and T-P were over $92{\sim}96%$, 99%, respectively. The continuous supply of organic carbon sources and the state of pH played important roles for the harmonious metabolism in anaerobic basin and the pH value of anaerobic basin maintained at about 9.0 for the period of the study.

• Journal of Korean Society on Water Environment
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• v.29 no.1
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• pp.74-80
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• 2013

The aim of this study is to evaluate color removal from leather-dyeing wastewater using $O_3$ and $O_3/H_2O_2$ unit processes and a serial process for $O_3$, followed by the $O_3/H_2O_2$ process. The color removal rate of the $O_3$ alone process was only 65% effective, and the color increased when an applied $O_3$ dose of more than 40 ~ 50 mg/L was applied. On the other hand, the color was completely removed without increments of color by the $O_3/H_2O_2$ process with $H_2O_2$ injection ratio of 0.2 and 0.3 (wt. $H_2O_2$/wt. $O_3$). Even though the injection of $H_2O_2$ had an effect on color removal, the color removal rates from $O_3$ alone and from $O_3/H_2O_2$ were similar up to the initial $O_3$-demand stage with an application of 0 ~ 40 mg/L $O_3$. In conclusion, it was found that the $O_3$ followed by the $O_3/H_2O_2$ serial process, the method injecting $H_2O_2$ after ozonation with $O_3$-demand (30 ~ 40 mg/L) in the first stage, is the most appropriate process for effective color removal from leather-dyeing wastewater.

• Fire Science and Engineering
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• v.33 no.2
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• pp.107-113
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• 2019

Recently, due to global warming, the trend shows an increase in number of lightning strikes which increase risk regarding industry infrastructures. Especially in case where the lightning strikes infrastructures including refinery, petorchemical plant facilities or storage tanks, it can cause power failures, electrical machine malfunction and damage which can lead to fire explosion and multiple calamities. Therefore, detailed case studies must be conducted through a systematic research regarding lightning strike accidents in order to understand its mechanism and devise preventive measures. This paper aims to study cases of explosion regarding waste water storage tanks in refineries and petrochemical plants in order to analyze its root cause and provide preventive measures for avoiding lightning related incidents.

• Membrane Journal
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• v.32 no.2
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• pp.83-90
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• 2022

Wastewater from refineries and petroleum plant lead to severe environmental pollution. There are various existing processes applied for oily water treatment, but membrane-based technology is one of the most efficient methods. Polymeric membranes prepared from organic materials for the separation of oil in water often face chronic problem of membrane fouling. Inorganic membranes are considered to be more efficient due to longer lifetime than organic membranes. Zeolite membranes have better chemical stability and long-term recyclability. The presence of hydrophilicity enhances the water flux of membrane. Ceramic membranes prepared from zeolites are another efficient class of inorganic membranes applied for oil water separation. This review is focused on oily wastewater separation based on zeolite membrane which classified into two categories, i) neat zeolite and ii) zeolite composites with other materials.