• Journal of the Korean Crystal Growth and Crystal Technology
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• v.18 no.5
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• pp.179-183
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• 2008

Employing screen printing technology, aluminum is applied to the back side of the n-type silicon wafer to see the effect of the heat treatment parameters on the Voc of the solar cell, Heat treatment at $850^{\circ}C$ produces the highest Voc among various heat treatment conditions. Heat treatment at the temperatures higher than $850^{\circ}C$ results in lower Voc, which is due to the destruction of the Al-Si alloy emitter layer. The destruction of Al-Si layer observed to be caused by the vigorous movement of silicon atoms toward aluminum layer during the heat treatment.

• Journal of Energy Engineering
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• v.14 no.2 s.42
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• pp.133-139
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• 2005

An activated carbon-photo catalysis hybrid system is proposed for the treatment of VOC produced from paint booth. and its VOC removal performance is experimentally evaluated. Activated carbon tower is designed on the basis of the adsorption characteristics of toluene. Photocatalytic system is designed as the series of $TiO_2/SiO\_2$ fluidized bed reactor and $TiO_2$-coated filters. The present activated carbon-photo catalysis hybrid system shows the VOC removal efficiency within $75\~100\%$ under different VOC species and concentrations.

• 한국연소학회:학술대회논문집
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• 2014.11a
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• pp.207-210
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• 2014

The potential of combustion treatment of low concentration VOC on a turbulent partially premixed flame has been studied experimentally. The significant decrease in hydrocarbon concentration from the low concentration VOC was observed with a turbulent partially premixed flame. The VOC/inert gas mixture whose fuel concentration is beyond the flammability limit could be treated in this method.

• Journal of the Korean Society of Combustion
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• v.22 no.1
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• pp.23-31
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• 2017

Large-scale fuel tanks emit massive amount of hardly-combustible VOC mixtures which are light hydrocarbon species in dilution with nitrogen and carbon dioxide. We have developed a lab-scale burner to combust those VOC mixtures by use of a turbulent partially-premixed flame as a pilot flame. For a higher HC treatment ratio, the mixture gases were reformed by a rotating arc plasma device. The results showed that the nitrogen mole fraction and the injecting speed of the VOC mixture influence on the performance of the burner. It was also found that the size of the pilot flame and the power supplied to the plasma device determine the overall HC treatment ratio and the concentrations of CO and NOx in the exhaust gas.

• Korean Chemical Engineering Research
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• v.51 no.1
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• pp.136-143
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• 2013

In this study, both transient behaviors of a biofilter system with improved design and a conventional biofilter were observed to perform the treatment of waste air containing malodor and volatile organic compound (VOC). Their behaviors of removal efficiency and treated concentration of malodor and VOC were compared each other. During 1st~7th stages of improved biofilter system operation it was observed that the order of treated ethanol concentration at each sampling port was switched due to the difference of microbe-population-distribution in spite of the difference of biofilter effective height. However, at 8th stage of its operation, the order of treated ethanol concentration at each sampling port was consistent to the order of biofilter effective height at each sampling port. The same was applied to the case of hydrogen sulfide, even though the difference of switched treated-hydrogen sulfide-concentrations was less than that of switched treated-ethanol-concentrations. The ethanol-removal efficiency of the biofilter system with improved design was ca. 96%, which was greater by 2% than that of the conventional biofilter. The transient behavior of treated hydrogen sulfide concentration of both biofilters were similar to each other. However, the concentration of hydrogen sulfide treated by the biofilter system with improved design was observed lower than that by the conventional biofilter. The hydrogen sulfide-removal efficiency of the biofilter system with improved design was higher by ca. 2% than that of the conventional biofilter. Therefore, the hydrogen sulfide-removal efficiency of the biofilter system with improved design was observed to be enhanced by the same as its ethanol-removal efficiency.

• Journal of Korean Society for Atmospheric Environment
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• v.19 no.1
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• pp.101-112
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• 2003

Biological methods are frequently used for treatment of contaminated air, containing volatile organic compounds and odor compounds in low concentrations and high flow rate of air streams. For more than 20 years. biofilter has been recognized as a cost effective technology for the purification of contaminated air. Most commercial applications before 1990 were for control of odors. In the past decades major progress has been accomplished in the development of vapor phase bioreactor. in particular biotrickling filers. Biotrickling filters are more complex than biofilters. but are usually more effective, especially for the treatment of compounds which are difficult to degrade or compounds that generate acidic by-products. While the level of understanding of biotrickling filtration process for VOCs still remains limited. the evidence success of biotreatment of VOC in air resulted in pursuing active research. This paper presents fundamental and practical aspert of VOCs treatment from air in biotrickling filter. Special emphasis is given to the operating parameters and the factors influencing performance for biotrickling filter.

• Journal of Environmental Science International
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• v.12 no.7
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• pp.825-833
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• 2003

The emission of volatile organic compounds (VOCs) generated from painting and coating processes is a worldwide problem as contributing factors to the development of photochemical smog and other environmental problems. Common methods of reducing VOC emissions are adsorption on activated carbon, membrane separation, absorption, incineration, or catalytic oxidation. In this article, the environmental issues caused by VOC emissions and the trend of legislation against such emissions will be surveyed first. Several conventional control technologies will then be summarized and the characteristics of each process will be introduced. Lastly, some examples will be described to show the hybrid processes which have been industrially applied for the recovery of VOC.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2004.11a
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• pp.3-8
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• 2004

• Journal of Korean Society of Environmental Engineers
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• v.37 no.8
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• pp.492-497
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• 2015

VOCs (Volatile Organic Compounds) are generally generated in the painting process, or at the company and laundry where use organic solvents. The VOCs consist of various hydrocarbons and has low calorific value due to its dilution with atmospheric air. Therefore, the VOCs are difficult to burn by a conventional fuel combustor. In this study, a novel plasma dump combustor was proposed for the treatment of low calorific VOC gases. This combustor was designed a combination of the characteristics in a plasma burner, a dump combustor and a 3D matrix burner. The combustor has good structure for maintaining enough residence time and reaction temperature for stable flame formation and VOC destruction. For investigating the performance characteristics of the plasma dump combustor, an experiment was achieved for VOC feed rate, VOC injector position, etc. Toluene was used as a surrogate of VOC. The novel combustor gave better performance than a conventional combustor, showing that VOC destruction rate and energy efficiency were 89.64% and 12.27 kg/kWh respectively, at feeding rate of 450 L/min of VOC of 3,000 ppm of toluene concentration.

• Journal of environmental and Sanitary engineering
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• v.14 no.4
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• pp.41-49
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• 1999

The water treatment by was performed to remove VOC and organic substances in the multi-stage ozone contactor. Ozone is mainly utilized to change the chemical structures of organic substance, of which finally has the purpose to degrad them. The removal efficiency of VOC has 20~60% at the ozone concentration of 3 ppm, in case of trichloroethylene, its efficiency is reduced by 85% at the ozone contact time of 8 min. Design factors such as the number of stage, ozone concentration, zone contact time are determined for optimal treatment in the multi-stage contactor.