• 한국환경과학회지
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• 제11권7호
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• pp.743-748
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• 2002

UV photolysis process is little known in parts of air pollution treatment, so there are not many applications in field. Therefore we have to do more experiment and study application possibility for treatment of VOCs(Volatile organic compounds). To solve these problems, we have been studying for simultaneous application of this technology. It has shown that concentration of TCE and B.T.X., diameter of reactor and wavelength of lamp have effected on decomposition efficiency. Analysis of TCE and B.T.X. concentration was carried out by GC-FID. A cylinderical reactor consisting of a quartz tube and a centrally located lamp(${\psi}25mm$) was used. The length and diameter of reactor were 1800mm, 75mm. It has shown that the generated ozone concentration goes up 250ppm when using 64watt ozone lamp. When using Photolysis process only, the rates of fractional conversion of each material are TCE 79%, Benzene 65%, Toluene 68%, Xylene 76%. This phenomenon can be rationalized in terms of the different bond energy that indicates how easily VOCs species can be decomposed.

• 환경위생공학
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• 제14권3호
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• pp.10-21
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• 1999

The purpose of study were to research the characteristics of water variation adding humic acids to distilled water after ozonation. Upon investigating pH variation with contact time after providing distilled water+air, distilled water+ozone and distilled water-humic acid-air in reactor, it reduced after 60 minute in inletting air and in spite of short contact time did suddenly in inletting ozone. TOC and UV-254 continued to increase with contact time of ozone and humic acids. $NH^{4+}-N$ did slowly increase or decrease after constant contact time of ozone, because $NH^{4+}-N$ was converted into $No^3-N$ by ozone. T-N did suddenly increase after 90minute, but T-P did rarely fluctuate for total experiment. Total 30 species of organic matter were detected by GS/MSD, but 14 species did really tend to increase except for matter identified in distilled water and blank test. Humic acids generated $aliphatic{\cdot}aromatic$ hydrocarbon, alcohol and amine etc., and did various matters without inflow course of contaminants.

• Journal of Astronomy and Space Sciences
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• 제17권2호
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• pp.277-284
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• 2000

KARI(Korea Aerospace Research Institute) has measured the ozone density profiles over the Korean Peninsular since the launch of the Korean Sounding Rocket-I (KSR-I) in 1993. The purpose of ozone measurements is to obtain the stratospheric and mesospheric vertical ozone density profiles over the Korean Peninsular with solar UV radiometers. With the visible channel of the radiometer, the attitude variation of the rocket was corrected and compensated. Developed system is based on ozone detector designs onboard the KSR-I and KSR-II. We discuss the development of ozone detector which will be onboard the KSR-III and its circuit and vibration test results for EM model.

• 대한환경공학회지
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• 제29권4호
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• pp.419-424
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• 2007

깨끗하고 안전한 수돗물에 대한 소비자들의 욕구가 커짐에 따라 막, 오존, 활성탄 등 다양한 고도처리공정이 정수장에 도입되고 있다. 본 연구에서는 고도처리공정의 도입으로 인한 관로 내 잔류염소 감소 및 THM 생성특성에 대하여 살펴보았다. 오존, 활성탄, 오존/GAC 공정별 DOC 제거특성과 bottle test를 이용한 잔류염소 감소 및 THM 생성특성을 평가하였다. 모든 처리공정에서 DOC 제거율보다 $UV_{254}$ 유발물질의 제거율이 우수한 것으로 나타났다. 특히, 오존공정에 의한 DOC 제거율은 기존 모래여과수 대비 약 4%에 불과하였으나, $UV_{254}$는 약 17%로 DOC 제거율보다 훨씬 더 큰 차이를 보였는데, 이는 오존에 의해 소수성 유기물이 친수성 유기물로 변환되었기 때문이다. 오존/GAC 공정이 유기물 제거에 가장 효과적이었으며, 모래여과, 오존, GAC, 그리고 오존/GAC공정을 거친 처리수의 잔류염소 감소계수는 각각 0.0230, 0.0307, 0.0117 그리고 0.0098 $hr^{-1}$ 나타났으며, 190시간 반응 이후 모래여과수는 THM이 81.8 ${\mu}g/L$ 생성된 반면, 오존, GAC, 그리고 오존/GAC의 처리수는 모래여과수에 비해 각각 6.0, 26.2, 30.3% 적게 생성되었다. 결론적으로 고도처리공정에 의해 관로 내 잔류염소의 지속성이 증대되었으며, THM 생성 또한 감소하는 것으로 나타났다.

• 한국작물학회지
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• 제42권3호
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• pp.338-343
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• 1997

벼 품종의 오존 저항성 판단을 위한 시험에서 오존의 처리농도는 0.3 ppm이 0.1 ppm보다 뚜렷한 결과를 보였고, 처리시간은 2∼4시간이 알맞은 것으로 나타났다. 묘대일수에 따른 저항성 정도는 파종후 3주까지는 생육이 진전될수록 높아지는 경향이었으나 3∼5주간에는 큰 차이가 없었다. 인디카와 통일형 품종들이 자포니카 품종보다 저항성이 높은 경향이었고, 자포니카 품종 중에서 장안벼외 7 품종은 높은 저항성을 나타내었다. 벼의 생육시기에 따른 피해엽율은 간척벼는 유묘기에서 밀양 2003외 4 품종은 최고 분열기에서 가장 높게 나타났고 임실율은 수잉기 처리에서 가장 낮았다.

• 대한환경공학회지
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• 제27권11호
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• pp.1162-1167
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• 2005

축산폐수는 고농도의 난분해성 유기물질을 많이 함유하고 있기 때문에 처리하기가 매우 어려운 것으로 알려져 있다. 따라서 본 연구에서는 현장에 건설된 오존을 이용한 시스템인 DOF(Dissolved Ozone Flotation)와 PO2(Pressurized Ozone Oxidation)에 의한 축산폐수의 처리특성을 조사하였다. DOF-PO2의 유입수내에 존재하는 SS의 제거율은 94%를 상회하여 약 400 mg/L의 농도를 22 mg/L까지 낮출 수 있었다. $COD_{Mn}$의 제거율도 90%정도로 620 mg/L로 유입되어 63 mg/L로 유출되었다. $SCOD_{Cr}$은 890 mg/L 정도가 유입되었으며 82%가 제거되어 160 mg/L 정도로 유출되었다. UV-254흡광도는 96%제거 되었다. 특히 TP의 제거율은 98%가 넘었고 27 mg/L가 유입되어 0.35 mg/L만이 유출되었다. TN도 SS의 제거와 함께 68%정도 제거되었으나 오존에 의한 제거효과는 없었다. DOF-PO2시스템에 의한 고농도 오존산화공정을 미생물처리공정과 같이 적용할 경우 축산폐수처리공정의 방류수 수질기준을 맞출 수 있었다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 하계학술대회 논문집 Vol.4 No.2
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• pp.795-798
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• 2003

Toxic organics are of great environmental concern primarily because they are toxic to mammals and birds, and are relatively soluble in water to contaminate surface water and groundwater. In this study, the decomposition of phenol, a widely used organic, in aqueous solutions by Boron doped diamond(BDD) electrode was examined. Thin, Boron-doped conducting diamond films are expected to be excellent electrodes for industrial electrolysis. Boron-doped diamond (BDD) were used as anode for generating ozone gas by electrolysis of acid solution. In this work. we have studied ozone generating system using BDD electrode. In order to determine the ozone generation properties of diamond electrode, experimental conditions, electrolyte concentration, temperature, flow rate and reaction time were varied diversely. As a result, we could confirm that ozone gas was generated successfully and the performance of diamond electrode was stable for electrolyte while $PbO_2$ electrode was disintegrated. Actually we are found that ozone amount increased by lowering the temperature of electrolyte. Decomposition of phenol concentration in the reaction solution by photolytic ozonation( $UV/O_3$) was analyzed by HPLC epuipped with a UV detector.

• 한국수처리학회지
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• 제26권6호
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• pp.109-115
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• 2018

This study was conducted to solve the water shortage problem by reclaiming urine from homes or public places and using it as cleaning water for toilets. The process used in this experiment is a chemical oxidation process combining ozone, hydrogen peroxide, and UV. We set the key substance that is to be removed as chromaticity and conducted the experiment to remove it. If the quantity or concentration of injected ozone, UV, and hydrogen peroxide is insufficient, then the chromaticity will initially increase due to low oxidizing power, and will later decrease. In addition, the efficiency of removing chromaticity appeared to be higher, depending on the quantity of ozone injected, for medium concentrated urine than highly concentrated urine. However, the absolute quantity of removed chromaticity was about 68% higher for highly concentrated urine, when 16 g/hr of ozone was injected. The higher the pH level, the reaction time and efficiency of removing chromaticity were higher, and in normal conditions, in reference to a pH of 8.55, there was a 6% difference in efficiency between a pH level of 5.05 and a pH level of 10.12. Finally, when processing urine through an ozone-only process, COD decreased steadily over time, but DOC did not decrease. This is because ozone reacts selectively with organic matter.

• 수산해양교육연구
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• 제28권5호
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• pp.1319-1328
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• 2016

Since Ballast Water Management Convention has been effected, BWTS, applied to new-building vessels and existing vessels, have been developed from many countries with various treatment methods. However, BWTS is mainly typed Electrolysis, Ozone and UV type. Approximately 70 products have been type approved by the Flag Administrations. For the new-building vessels, the vessels' design and construction have been considered for arrangements and installations for BWTS. However, existing vessels which already construction had finished have problem with selection of BWTS type for installation and arrangement. The selection of the most economized BWTS system is important though, CAPEX has not been made any significant differences. However, OPEX is more important factor. Consequently, detail analysis of OPEX is the key to the selection of the most economized BWTS system and also it can be the purpose of this study. The feasibility study on the main three type of BWTS (Electrolysis, Ozone and UV type) for 175K Bulk Carrier and 57K Cargo ship has been conducted for this study. Because, these three type of BWTS have been the most frequently installed and used and the two type of object vessels are consist of the 40% of the world merchant ship market. For this study, interest rate, project duration (operation time after installation), maintenance cost and fuel oil price are considered as major factor of feasibility study. In addition, expecting Interest rates to sensitivity analysis conducted for more accurate feasibility study. For 175K Bulk carrier, ozone treatment system is more economical than other types. For 57K cargo ship, UV type is considered more economical than other types. However, it is concluded that electrolysis type is more suitable compare to installation space, total weight and electrical power consumption.

• 한국대기환경학회지
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• 제17권5호
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• pp.385-393
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• 2001

We have developed a Differential Absortion LIDAR (DIAL) method for the measurement of lower tropospheric ozone concentration. We used two laser beams from quadrupled Nd:YAG (266 nm) for the resonance wavelength and dye lasers (299.5 nm) for non -resonance wavelength. Aerosol extinction coefficients in the lower troposphere was computed by both Klett and Slope methods. To correct the SIN (Signal -Induced Noise) effect caused by photo detector, we subtracted a new-fitted baseline on the background part of a LIDAR signal, after the subtraction of the DC level. This is because SIN can be treated as an exponentially decaying tail. Using theme results, ozone profiles were obtained approximately 2km at daytime and 3km at nighttime. We compared the results derided by the Slope method with those measured by UV spectrometer. The computed results are in mostly good agreement with experimental results. In the measurement of the vertical layer, we observed the variation of the ozone profiles around the top mixed layer.