• Title, Summary, Keyword: gaseous ozone

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Application of Gaseous Ozone for Cleaning Biological Weapon Agent Contaminated Building (생물테러시 실내제독을 위한 효율적인 오존가스의 적용 방법)

  • Yoon, Je-Yong;Jeong, Woo-Dong;Mun, Sung-Min;Cho, Min
    • Journal of the Korea Institute of Military Science and Technology
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    • v.11 no.2
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    • pp.101-108
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    • 2008
  • This study attempted to develop the technology by gaseous ozone for decontaminating building affected by a model of biological weapon agent(Bacillus subtilis spores) instead of Bacillus anthracis spore. The use of ozone is attractive method from a practical point of view of decontamination procedure since it has strong oxidation power but no residue after application. We examined the disinfection efficiency of gaseous ozone to Bacillus subtilis spores which suspension was sprayed on different material surfaces and dried. Three different types of gaseous ozone was applied : dry ozone, dry ozone with humidified air, and water bubbled wet ozone. Dry ozone(1500ppm) failed to achieve any significant inactivation for 2hrs. However, six log reduction of B. subtilis spore was achieved within 30min by 1500ppm of water bubbled wet ozone. This result shows the noticeable inactivation efficiency by gaseous ozone compared with previous studies. Good performance by wet ozone was also found for military material surface.(i.e. : gas mask hood, protective garments, army peinted metal surface).

ULTRA-FINE PARTICLES AND GASEOUS VOLATILE ORGANIC COMPOUND EXPOSURES FROM THE REACTION OF OZONE AND CAR-AIR FRESHENER DURING METROPOLIS TRAVEL

  • Lamorena, Rheo B.;Park, Su-Mi;Bae, Gwi-Nam;Lee, Woo-Jin
    • Environmental Engineering Research
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    • v.12 no.2
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    • pp.72-80
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    • 2007
  • Experiments were conducted to identify the emissions from the car air freshener and to identify the formation of ultra-fine particles and secondary gaseous compounds during the ozone-initiated oxidations with emitted VOCs. The identified primary constituents emitted from the car air freshener in this study were $\alpha$-pinene, $\beta$-pinene, $\rho$-cymene and limonene. Formation of ultra-fine particles (4.4-160 nm) was observed when ozone was injected into the chamber containing emitted monoterpenes from the air freshener. Particle number concentrations, particle mass concentrations, and surface concentrations were measured in time dependent experiments to describe the particle formation and growth within the chamber. The irritating secondary gaseous products formed during the ozone-initiated reactions include formaldehyde, acetaldehyde, acrolein, acetone, and propionaldehyde. Ozone concentration (50 and 100 ppb) and temperature (30 and $40^{\circ}C$) significantly affect the formation of particles and gaseous products during the ozone-initiated reactions. The results obtained in this study provided an insight on the potential exposure of particles and irritating secondary products formed during the ozone-initiated reaction to passengers in confined spaces.

PAHs 오염 토양내 오존이동특성;함수율과 수분과 토양 유기물의 영향

  • 배기진;정해룡;최희철
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • pp.140-143
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    • 2001
  • The packed column experiments were conducted with commercial Jumunjin sand(SOM content : 0.01 %) and a field soil(SOM content : 0.08 %) in order to understand the effects of water content and soil organic matter(SOM) on the transport of gaseous ozone in unsaturated soil contaminated with phenanthrene. Water content and SOM content were artificially controlled. As water content increased, earlier breakthrough was observed in the beginning of BTC of ozone, because direct contact of gaseous ozone with SOM and phenanthrene was prevented by water film formed between soil particles and gaseous ozone. The total removal of phenanthrene in Jumunjin sand was not affected by water content which was more than 99% at different water content(4.4, 8, 17.3%). However, the removal in field soil at water content 6.5 % and 20 % was 98% and 80 %.

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불포화 토양내에서 가스상 오존 이동특성에 대한 Multiphase liquids의 영향

  • 정해룡;최희철
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • pp.124-127
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    • 2003
  • Laboratory scale experiments on in-situ ozonation were carried out to delineate the effects of liquid phases, such as soil water and nonaqeous phase liquid (NAPL) on the transport of gaseous ozone in unsaturated soil. Soil water enhanced the transport of ozone due to water film effect, which prevent direct reaction between soil particles and gaseous ozone, and increased water content reduced the breakthrough time of ozone because of increased average linear velocity of ozone and decreased air-water interface area. Diesel fuel as NAPL also played a similar role with water film, so the breakthrough time of ozone in diesel-contaminated soil was significantly reduced compared with uncontaminated soil. However, ozone breakthrough time was retarded with increased diesel concentration, because of high reactivity of diesel fuel with ozone. In multiphase liquid system of unsaturated soil, the ozone transport was mainly Influenced by nonwetting fluid, diesel fuel in this study.

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Effects of Gaseous Ozone Exposure on Bacterial Counts and Oxidative Properties in Chicken and Duck Breast Meat

  • Muhlisin, Muhlisin;Utama, Dicky Tri;Lee, Jae Ho;Choi, Ji Hye;Lee, Sung Ki
    • Food Science of Animal Resources
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    • v.36 no.3
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    • pp.405-411
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    • 2016
  • The effects of gaseous ozone exposure on the bacterial counts and oxidative properties were evaluated in duck and chicken breast fillets, which were stored under a continuous flux of gaseous ozone (10×10−6 kg O3/m3/h) at 4±1℃ for 4 d. The ozone generator was set to on for 15 min and off for 105 min, and this cyclic timer was set during storage. Ozone effectively reduced the growth of coliform, aerobic and anaerobic bacteria in both chicken and duck breast. However, lipid oxidation occurred faster in duck breast than chicken breast with higher degree of discoloration, TBARS value, and antioxidant enzyme (glutathione peroxidase and catalase) activity decline rates. It is concluded that ozone effectively controlled the growth of bacteria in both chicken and duck breast with less effects on oxidative deterioration in chicken breast.

Evaluating Effective Volume and Hydrodynamic Behavior in a Full-Scale Ozone Contactor with CFD Simulation (전산유체역학을 이용한 실규모 오존 접촉에서의 수리거동과 유효 체적 평가에 관한 연구)

  • Park, No-Suk;Mizuno, Tadao;Tsuno, Hiroshi;Bea, Chul-Ho;Lee, Seon-Ju
    • Journal of Korean Society of Water and Wastewater
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    • v.18 no.5
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    • pp.656-665
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    • 2004
  • An Ozone reaction model combined with CFD(Computational Fluid Dynamics) technique was developed in this research, in the simulation of ozonation, hydrodynamic behavior as well as reaction model is important because ozone is supplied to treated water as gas ozone. In order to evaluate hydrodynamic behavior in an ozone contactor, CFD technique was applied. CFD technique elucidated hydrodynamic behavior in the selected ozone contactor, which consisted of three main chambers. Three back-mixing zones were found in the contactor. The higher velocities of water were observed in the second and third compartments than that in the first compartment. The flow of the opposite direction to the main flow was observed near the water surface. Based on the results of CFD simulation, the ozone contactor was divided into small compartments. Mass balance equations were established were established in each compartment with reaction terms. This reaction model was intended to predict dissolved ozone concentration, especially. We concluded that the model could predict favorably the mass balance of ozone, namely absorption efficiency of gaseous ozone, dissolved ozone concentration and ozone consumption. After establishing the model, we discussed the effect of concentration of gaseous ozone at inlet, temperature and organic compounds on dissolved ozone concentration.

Influence of LNAPL and Soil Water on Migration of Gaseous Ozone in Unsaturated Soils (불포화 토양내에서 가스상 오존 이동특성에 대한 LNAPL과 토양수분의 영향)

  • Jung, Hae-Ryong;Choi, Hee-Chul
    • Journal of Soil and Groundwater Environment
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    • v.10 no.6
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    • pp.63-67
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    • 2005
  • Laboratory scale experiments were carried out to delineate the effects of liquid phases, such as soil water and light nonaqeous phase liquid (LNAPL) on the transport of gaseous ozone in unsaturated soil. Soil water enhanced the transport of ozone due to water film effect, which prevents direct reaction between soil particles and gaseous ozone, and increased water content reduced the breakthrough time of ozone because of increased average linear velocity and decreased air-water interface area. Diesel fuel as LNAPL also played a similar role with water film, so the breakthrough time of ozone in diesel-contaminated soil was significantly reduced compared with uncontaminated soil. Ozone breakthrough time was retarded with increased diesel concentration, however, because of high reactivity of diesel fuel with ozone. In unsaturated soil containing two liquids of soil water and LNAPL, the transport of ozone was mainly influenced by nonwetting fluid, diesel fuel in this study.

A Study on the Trial Manufacture and Characteristics of Lamp Type Ozonizer (Lamp 형 오존발생기의 시작 및 특성에 관한 연구)

  • Kim, Sang-Ku;Song, Hyun-Jig;Kang, Cheon-Su;Park, Won-Zoo;Lee, Kwang-Sik;Lee, Dong-In
    • The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.10 no.6
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    • pp.62-72
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    • 1996
  • In this paper, ozonizer using U-type lamp(Olamp) has been designed and manufactured, which can perform a role of lighting source and ozonizer by using photo and chemical methods. The discharge, spectrum, illuminance, ozone concentration, ozone generation, ozone yield and sterilization characteristics of Olamp have been studied. The important conclusions obtained from this paper can be summa'||'&'||'not;rized as follows. As a result of spectrum characteristics for Olamp, ultraviolet ray of a short wave'||'&'||'not;lengths and a visible ray are radiated. The illuminance of Olamp was found to be useful for "color distinctive and intermittent works in the dark working spaces" in accordance with KS A 3011. The ozone concentration of gaseous phase is inversely proportional to quality of supplied gas. Also, ozone conce tration and generation of gaseous phase are rised more commercial oxygen gas than those trial air gas for constant quality of supplied gas. Ozone generation and ozone yield of gaseous phase are proportion'||'&'||'not;al to ozone concentration of gaseous phase. The characteristics of liquid ozone concentration at distilled water are proportional to circulating velocity of fermentation chamber and ozone concentration of gas'||'&'||'not;eous phase. As a result, the sterilization characteristics of Escherichia coli have been obtained more than 97[ % J.

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Effects of Operating Parameters on Dissolved Ozone and Phenol Degradation in Ozone Contact Reactor (오존 접촉 반응기의 용존 오존 농도 및 페놀 분해에 미치는 운전변수의 영향)

  • Chung, Jae-Woo;Park, Jeong-Wook;Lee, Chun-Sik
    • Journal of Korean Society of Environmental Engineers
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    • v.32 no.3
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    • pp.241-247
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    • 2010
  • The Effects of operating parameters such as initial pH, gaseous ozone concentration, supplied gas flow rate on dissolved ozone concentration and phenol degradation in ozone contact reactor were investigated. Dissolved ozone concentrations were saturated to constant values after a certain ozone contact time. The saturation values were influenced by experimental parameters. Dissolved ozone concentration decreased with the increase of initial pH because the ozone is unstable in high pH regions. The gaseous ozone concentration in a constant gas supply affected the saturation concentration of dissolved ozone and the injection rate of gas with a constant ozone concentration determined the rate to reach dissolved ozone saturation. Effects of operating parameters on phenol degradation were closely related with those of parameters on dissolved ozone concentration. Phenol degradation was enhanced by the increase of initial pH, because the degradation of dissolved ozone gave birth to free radicals which have much higher reactivity with phenol. Increase of gaseous ozone concentration and gas flow rate promoted the phenol degradation through the generation of dissolved ozone which plays the role in phenol degradation. The injection of methanol deteriorated the phenol degradation through the scavenging effect on OH radicals.

Photodegradation of Gaseous Toluene Using Short-Wavelength UV/TiO2 and Treatment of Decomposition Products by Wet Scrubber (단파장자외선/TiO2 공정에 의한 가스상 톨루엔의 분해 및 습식세정장치에 의한 분해생성물의 제거)

  • Jeong, Ju-Young;Jurng, Jong-Soo
    • Journal of Environmental Science International
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    • v.16 no.4
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    • pp.433-440
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    • 2007
  • The photodegradation and by-products of the gaseous toluene with $TiO_2$ (P25) and short-wavelength UV ($UV_{254+185nm}$) radiation were studied. The toluene was decomposed and mineralized efficiently owed to the synergistic effect of photochemical oxidation in the gas phase and photocatalytic oxidation on the $TiO_2$ surface. The toluene by the $UV_{254+185nm}$ photoirradiated $TiO_2$ were mainly mineralized $CO_2$ and CO, but some water-soluble organic intermediates were also formed under severe reaction conditions. The ozone and secondary organic aerosol were produced as undesirable by-products. It was found that wet scrubber was useful as post-treatment to remove water-soluble organic intermediates. Excess ozone could be easily removed by means of a $MnO_2$ ozone-decomposition catalyst. It was also observed that the $MnO_2$ catalyst could decompose organic compounds by using oxygen reactive species formed in process of ozone decomposition.