• Journal of the Korea Institute of Military Science and Technology
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• v.5 no.3
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• pp.105-112
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• 2002

A combined process of non-thermal plasma and catalytic techniques has been investigated to treat toxic gas compounds in air. The treated gas in the present study is $CH_3$CN that has been known to be a simulant of toxic chemical agent. A planar type dielectric barrier discharge(DBD) reactor has been used to generate non-thermal plasma that produces various chemically active species, O, N, OH, $O_3$, ion, electrons, etc. Several different types of adsorbents and catalysts, which are MS 5A, MS 13X, Pt/alumina, are packed into the plasma reactor, and have been tested to save power consumption and to treat by-products. Various aspects of the present techniques, which are decomposition efficiencies along with the power consumption, by-product analysis, reaction pathways modified by the adsorbents and catalysts, have been discussed in the present study.

• Proceedings of the KSME Conference
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• 2000.11b
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• pp.715-719
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• 2000

It is reported that we are facing the serious environment pollution difficulties such as acid rain, green house effects, etc. The gaseous matter CO, NOx, SOx, VOCs which are regarded as main factors for these current pollutions are mainly emitted from power plants and vehicles. Therefore several leading countries are regulating the related laws strictly, especially exhaust emissions from a Diesel engine without an after treatment device. The Objective of this study is to find out NOx removal characteristics focused on emissions of a Diesel engine using radical at each engine speed and load. It is generated from outer air and put into a mixing chamber in the end of exhaust line. In addition, the optimum temperature condition to activate reaction by radical is experimentally carried out. Concentration of exhaust emissions is analyzed from the gas anlayzer(KaneMay) and FTIR to estimate by-products.

• Clean Technology
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• v.22 no.2
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• pp.96-105
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• 2016

VOCs emissions from industries cause the air pollution and odor. In the industrial facilities, the existing odor treatment techniques have limits and problems. In this study, the optimum essential oil and metal oxide selected by screening test. lavender oil, cypress oil and TiO₂ were determined by deodorant materials and those were blended by 5%, 45%, 10%, respectively. In addition, the result of batch type experiments depending on the dilution rate, injection, rate, temperature showed that the optimum condition of deodorant is 6 mL of injection rate, and 200 times of dilution rate and the removal efficiency increased in proportion with temperature. In addition, the activation energy was calculated from the rate equation, which appeared in the 3-4 times lower than conventional deodorants.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.93-94
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• 2001

Biofilter operating parameters such as incoming VOCs concentrations, temperature, and packing materials were studied. The performance of a lab-scale biofilter in the treatment of air contaminated with mixtures vac has been evaluated in this study. The biofilter was operated for 80 days packed with compost. Empty bed residence time (EBRT) was 3 to 1.5 min. After 80 days of operation, the removal efficiency was 94% and 73% at $25^{\circ}C$ and $45^{\circ}C$, respectively. Removal efficiencies of m-xylene (93%), o-xylene (92%) and toluene (92%) were better than that of benzene (84.7%).

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 1996.11a
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• pp.50-53
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• 1996

This paper reports the experimental results for the determination of the overall partition coefficient of VOCs in unsaturated soil, A chromatographic method was used for the determination of gaseous partition coefficients to natural soil under various water content conditions. The equilibrium vapor pressure of water over saturated salt solution was used to fix the relative humidity of the air and control the water content of the soil systems. The transport behavior was studied for dichloromethane, trichloroethane and dichlorobenzene pollutants, with log octanol-water partition coefficients(log $K_{ow}$ ) which range from 1.25 to 3.39, or water to soil partitioning which varies by 135 times; water solubility constants which vary by 3 times; and vapor pressures which range from 1 to 362 torr. Water content of the soil had a pronounced effect on the effective partition coefficient(between gas and soil + water stationary phase) as well as on the effective dispersion coefficient.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2005.11a
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• pp.295-300
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• 2005

This Study intends to find out the subjective symptom of Construction Business Worker caused by chemical material exposure, also willing to research how much they are exposed to VOCs(Volatile Organic Compounds) and under how much harmful circumstance they are working. As the results, the job group among construction business workers which is most highly dangerous degree to be taken ill of Multiple Chemical Sensitivity is Interior Worker, next following by order of Clerical Worker, Exterior Worker. According to this result, the continuous exposure in high density must be prevented by the measures for Interior Worker also to be bestowed a compulsory break during working hour for regular exposure to the open air,

• Journal of the Korean Geosynthetics Society
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• v.6 no.3
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• pp.9-16
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• 2007

Soil vapor extraction (SVE) is an effective and cost efficient method of removing volatile organic compounds (VOCs) and petroleum hydrocarbons from unsaturated soils. Incorporating PVDs in an SVE system can extend the effectiveness of SVE to lower permeability soils by shortening the air flow-paths and ultimately expediting contaminant removal. With this approach, the real bounded system is replaced for the purposes of analysis by an imaginary system of infinite areal extent. The boundary conditions for the contaminant remediation model test include constant head and no flow condition. Due to these parallel boundaries conditions, image wells should be developed in order to maintain the condition of no flow across the impermeable boundary. It is also assumed that the flow is drawdown along the constant head boundary condition. The factors contributing to the difference between the theoretical and measured pressure heads were also analyzed. The flow factor increases as the flow rate is increased. The flow rate is the most important factor that affects the difference between the measured and theoretical pressure heads.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.1
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• pp.151-155
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• 2007

A compact discharge plasma system with a photocatalyst has been proposed and investigated experimentally for application to air conditioners. It was found that there was intense ultra violet radiation with high energy of 3.2 eV from the corona discharge due to the DC-biased pulse voltage applied on a wire. An electrophotochemical reaction took place apparently on the surfaces of the photocatalyst of $TiO_2$ irradiated ultra violet front the discharge plasma in the proposed plasma system. The proposed discharge plasma system with the photocatalyst of $TiO_2$ showed very high removal efficiency of VOCs by tile additional electrophotochemical reactions on the photocatalyst. The proposed discharge plasma system also showed very high removal efficiency of particles such as smokes, suspended bacteria, and pollen and mite allergens by the electrostatic precipitation part. This type of corona discharge plasma system with a photocatalyst can be used as an effective means of removing both indoor pollutant gases and particles including suspended allergens.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.05b
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• pp.362-363
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• 2003

Photochemical ozone is formed from nitrogen oxides (NOx) and volatile organic compounds(VOCs) through non-linear interactions between chemical reactions and meteorology, and the relationship between precursors and photochemical ozone will be changed to match the emission distribution and meteorological fields. It is generally known that for some conditions the process of ozone formation is controlled almost entirely by NOx and is largely independent of VOC, while for other conditions ozone production increases with increasing VOC and does not increase(or sometimes even decreases) with increasing NOx (omitted)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.05b
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• pp.167-168
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• 2003

광화학 스모그는 대기 중으로 배출된 일차 오염물질인 /NO$_{x}$와 휘발성 유기화합물(volatile organic compounds)이 햇빛에 의해 반응하여 오존과 그외 다른 광화학 물질들을(photochemical oxidants) 생성시키는 현상이다. 서울의 경우 이런 VOCs 중에서 가장 많은 양을 차지하는 톨루엔은 광화학 반응을 통해 이차 유기 에어로졸(secondary organic aerosols)을 생성하는 능력이 매우 높은 방향족 화합물이다(Na and Kim, 2001). 지금까지 톨루엔의 이차 유기 에어로졸 생성에 관한 연구와 다른 방향족 탄화수소에 관한 연구가 스모그 챔버 실험을 통해 많이 이루어져 왔다. (중략)