• 대한환경공학회지
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• 제33권7호
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• pp.516-522
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• 2011

국내에서 운영중인 혐기성 소화조의 가장 큰 문제점은 낮은 소화효율이며, 이에 대한 원인은 낮은 유기물 투입농도, 소화조내의 낮은 교반 효율, 잉여슬러지의 난분해성 등이다. 본 연구에서는 혐기성 소화설비의 효율성을 높이기 위하여 기존의 혐기성 소화 시스템에 농축 및 교반, 오존 가용화 설비를 설치하고, 기존의 2단 소화조에서 단단소화조로 개선함으로서 소화효율 및 바이오가스의 발생량을 증대 시키고자 하였다. 이러한 개선을 통하여 농축시스템의 슬러지 농도는 2.6배 향상되었음을 확인하였으며, 농축효율은 3.0배 증가한 것으로 나타났다. 또한, 기계식 교반으로 사공간이 줄어들었음을 확인하였으며, 혐기성 소화조 내 소화가스 발생량도 평균 $193.8m^3$/일에서 평균 $386.0m^3$/일로 향상된 것을 확인하였다. 소화효율은 평균 47.6%에서 54.6%로 향상되어진 것으로 나타났으며, VS제거당 소화가스 발생량은 평균 $0.30Nm^3/kg$ VS removal에서 $0.42Nm^3/kg$ VS removal로 증대되어진 것으로 나타났다.

• 환경위생공학
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• 제15권2호
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• pp.95-101
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• 2000

산업의 고도화에 따른 경제성장으로 인류의 삶의 질은 많이 좋아졌지만 경제활동으로 인한 각종 환경 오염물질은 상대적으로 많이 배축된 것이 사실이다. 특히 대기오염물질의 주 요인이 되고있는 질소산화물과 아황산가스 등 많은 오염물질이 있지만 최근 더욱더 문제가 되고있는 것이 휘발성 유기화합물질로써 대기중의 탄화수소 화합물의 총칭으로 광 화학 옥시던터와 오존 등으로 인한 대기오염으로 인체에 미치는 영향이 아주 심각하며, 발생장소도 대규모 석유화학 장치산업의 원유를 정제하는 정제공정에서부터 저유소 및 중간 제품공정, 그리고 소비자가 직접 접하는 전국각지에 산재되어 있는 주유소 등에서 많은 량의 휘발성 유기화합물질이 발생되고 있다. 이에 대한 대책으로 정부차원에서 우선 대규모 석유화학단지를 휘발성 유기화합물질 배출저감을 위한 종합대책지역으로, 전남 여천지역은 1996. 9. 20일, 울산지역은 1997. 7. 1일에 지정고시 하였다. 울산지역의 경우 당초 대상물질이 47개 항목에서 시행초기에 보완적인 차원에서 크실렌 및 초산 등 일부물질이 수정된 31개 항목으로 변경고시 되었으며, 이에 대해 사업장에서는 해당물질에 따른 처리시설을 설치 가동 중에 있다. 그러나 휘발성 유기화합물질의 발생조건과 발생량, 각 물질의 혼합시 안전성문제 등이 공정조건상 일정하지 않아 방지시설 선정설치에 많은 에로사항이 있었다. 기존의 시설에 방지시설을 추가한다는 것은 화학공장 특성상 여러 가지 조건이 있으며, 그 동안 많은 시행착오를 하면서 설치하였다. 그러나 일부시설은 아직도 완벽한 방지효과를 얻기에는 부족하므로 향후 계속적인 기술 및 설비투자와 관리대책이 보완되어야 할 것으로 사료된다.

• 한국물환경학회지
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• 제34권2호
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• pp.149-156
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• 2018

Oxidation of Ciprofloxacin, Trimethoprim, and Enrofloxacin by ozone was experimentally investigated to observe the effects of background water quality (such as ultrapure water, humic acid, and biologically treated wastewater) and water temperature on the removal rate of these antibiotics, and, thereby, to be able to provide design information when the ozone treatment process is adopted. Initial concentrations of the antibiotics spiked to $10{\mu}g/L$, and the ozone dose was 1, 2, 3, 5, and 8 mg/L. While the removal rate of Ciprofloxacin under ultrapure water background by ozone oxidation was over 99%, the removal rate under humic acid and biologically treated wastewater background was markedly lower, in the range of 49.3% ~ 99% and 19.8 % ~ 99 %, respectively. When water temperature is decreased from $20^{\circ}C$ to $4^{\circ}C$, the removal rate is reduced from the range of 19.8% ~ 99 % to the range of 7.5 % ~ 99 % under a biologically treated wastewater background. The effects of background and temperature on the removal rate of Trimethoprim and Enrofloxacin were similar to that of Ciprofloxacin, but the degree was different. Therefore, it is concluded that the background of water to be treated, as well as water temperature, should be taken into consideration when the design factor, such as ozone dose, is determined, so that the treatment objective of the ozone treatment process can be most effectively met.

• 상하수도학회지
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• 제11권2호
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• pp.65-75
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• 1997

Removal characteristics of volatile organic carbons(VOCs) by ozone oxidation and other processes in the raw water of the 1st Nakdong water treatment plant were investigated. Dichrolomethane, toluene and other 7 compounds were detected in the raw water. With regard to detected 4 compounds in finally treated water, it was found that VOCs could not be removed effectively by traditional water treatment process. Benzene, 1,2-dichlorobenzne were not detected in the raw water but they were detected in the process of treatment. The compound of highest detection frequency was dichloromethane. When the raw water was controlled at pH 7, temperature $20^{\circ}C$, 5 minutes as contact time, 10 minutes as reaction time, the removal rate of THMFP, $KMnO_4$ demand, TOC, $UV_{254nm}$ and $NH_3-N$ were 46.4%, 22%, 19.6%, 31% and 8%, respectively. From estimating the finally treated water qualities in 7 kinds of treatment processes, P-6 process(raw water-chlorination-coagulation-ozonation) was most effective for organics removal and THMs control. Removal efficiencies for $KMnO_4$ demand and TOC by the process which combined preozonation with coagulation was twice better than only preozonation. $NH_3-N$ removal rate was shown as 10% by P-3 process(raw water-coagulation-ozonation), but 83% of $NH_3-N$ was removed by P-4 process(raw water-coagulation-chlorination). It was found that the chlorination is more effective than the ozonation for the NH3-N removal as commonly known.

• Korean Chemical Engineering Research
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• 제48권4호
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• pp.540-543
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• 2010

가스 중에 포함되어 있는 질소산화물을 안전하게 처리하기 위하여 저온 플라즈마 반응기를 제작하여 반응기내에 공급되는 반응물질의 유량과 방전주입전력량에 대한 장치의 특성을 실험적으로 조사하고, 유효성을 검정하였다. 반응가스는 $NO/N_2$ 혼합가스와 $N_2/O_2$ 혼합가스를 이용하여 초기 NO 농도를 설정하고, 유속을 1~4 l/min으로 공급하였다. 반응물질의 유량이 증가할 때 NO의 감소율이 낮고, 방전주입전력이 높을 때 NO의 분해가 용이하였다. 또한 반응물질의 지연시간이 길고 방전주입전력이 높을수록 NO의 분해에너지 효율이 높았으며, 유량이 많고 방전 주입 전력량이 증가할수록 오존의 생성량이 증가하였다.

• 한국염색가공학회지
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• 제30권1호
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• pp.51-61
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• 2018

In this study, effluent water was produced through Submerged Membrane Bio-Reactor(SMBR) process, which is a simple system and decomposes organic matter contained in wastewater with biological treatment process and performs solid-liquid separation, Especially, ozone oxidation treatment process is applied to effluent water containing fluorescent whitening agent, which is a trace pollutant which is not removed by biological treatment, and influences the quality of reused water. The concentration of $COD_{Cr}$ in the SMBR was $449.3mg/{\ell}-COD_{Cr}$, and the concentration of permeate water was $100.3mg/{\ell}-COD_{Cr}$. The removal efficiency was about 70.1%. The amount of ozone required for the removal of the fluorescent whitening agent in the permeated water in SMBR was $6.67g-O_3/min$, and the amount of ozone required to remove $COD_{Mn}$ relative to the permeate water was calculated to remove $0.997mg-COD_{Mn}$ for 1mg of $O_3$.

• 한국지하수토양환경학회지:지하수토양환경
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• 제15권6호
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• pp.37-45
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• 2010

Surfactant-enhanced ozone sparging (SEOS), an advanced version of SEAS (surfactant-enhance air sparging) was introduced in this study for the first time for removal of non-volatile contaminant from aquifer. The advantages of implementing SEAS, enhanced air saturation and expanded zone of sparging influence, are combined with the oxidative potential of ozone gas. Experiments conducted in this study were tow fold; 1-dimensional column experiments for the changes in the gas saturation and contaminant removal during sparging, and 2-dimensional box model experiment for the changes in the size of zone of influence and contaminant removal. An anionic surfactant (SDBS, sodium dodecylbenzene sulfonate) was used to control surface tension of water. Fluorescein sodium salt was used as a representative of watersoluble contaminants, for its fluorescence which is easy to detect when it disappears due to oxidative degradation. Three different gases (air, high-concentration ozone gas, and low-concentration ozone gas) were used for the sparging of 1-D column experiment, while two gases (air and low-concentration ozone gas) were used for 2-D box model experiment. When SEOS was performed for the column and box model, the air saturation and the zone of influence were improved significantly compared to air sparging without surface tension suppression, resulted in effective removal of the contaminant. Based on the experiments observations conducted in this study, SEOS was found to maintain the advantages of SEAS with further capability of oxidative degradation of non-volatile contaminants.

• 한국물환경학회지
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• 제24권1호
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• pp.63-68
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• 2008

This study was performed to assess the potential use of ozone or UV radiation for the treatment of water contaminated with sulfamethoxazole (SMX), which is frequently used antibiotic in human and veterinary medicines, especially focusing on the kinetic study and effect of pH. In a study using ozone alone, kinetic study was performed to determine second-order rate constant ($k_{O3,SMX}$) for the reactions of SMX with ozone, which was found to be $1.9{\times}10^6M^{-1}s^{-1}$ at pH 7. The removal efficiencies of SMX by ozone were decreased with increase of pH due to rapid decomposition of ozone under the condition of various pH (2.5, 5.3, 7, 8, 10). In a UV irradiation study at 254 nm, a kinetic model for direct photolysis of SMX was developed with determination of quantum yield ($0.08mol\;Einstein^{-1}$) and molar extinction coefficient ($15,872M^{-1}cm^{-1}$) values under the condition of quantum shielding due to the presence of reaction by-products formed during photolysis. For effect of pH on photolysis of SMX, SMX in the anionic state ($S^-$, pH > 5.6), most prevalent form at environmentally relevant pH values, degraded more slowly than in the neutral state (SH, 1.85 < pH < 5.6) by UV radiation at 254 nm.

• 조명전기설비학회논문지
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• 제22권8호
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• pp.75-81
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• 2008

본 논문은 플라즈마를 이용한 수처리 연구를 수행하였다. 이 연구에 사용한 수중플라즈마 토치는 상당한 전력의 절감을 가져올 수 있기 때문에 경제적인측면과 에너지효율면에서 뛰어난 결과를 나타내었다. 수중에서 일어나는 스트리머방전과 아크방전 현상을 면밀히 조사하여 비교하였고, 또한 염색페수를 플라즈마로 처리하였을 시의 색도제거율과 용존오존, 과산화수소와의 상관관계를 알기위해 표본화하고 분석하였다. 이에 플라즈마토치에는 선택적인 산화반응이 다소 있긴 하지만, 플라즈마화학반응에 의한 $H_2O_2$와 $O_3$의 성장이 아크방전 보다 스트리머방전시 더 효과적으로 촉진된다는 것을 알 수 있었다. 따라서 스트리머방전이 아크플라즈마 토치에 비해 더 효율적인 플라즈마 화학반응을 일으킬 수 있는 환경을 만들어주므로, 수처리에 있어서 스트리머플라즈마토치가 더 적합하였다.

• 한국염색가공학회지
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• 제19권3호
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• pp.26-36
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• 2007

This study was carried out to treat the aqueous solutions containing reactive dyes(RB19, RR120 and RY179) by the Ozone demand flask method and adsorption process using activated carbon fiber(ACF) which are one of the main pollutants in dye wastewater. Ozone oxidation of three kinds of the reactive dyes was examined to investigate the reactivity of dyes with ozone, competition reaction and ozone utilization on various conditions for single- and multi-solute dye solution. Concentration of dyes was decreased continuously with increasing ozone dosage in the single-solute dye solutions. Competition quotient values were calculated to investigate the preferential oxidation of individual dyes in multi-solute dye solutions. Competition quotients(CQi) and values of the overall utilization efficiency, ${\eta}O_3$, were increased at 40mg/l of ozone dosage in multi-solute dye solutions. ACF(A-15) has much larger specific surface area$(1,584m^2/g-ACF)$ in comparison with granular activated carbon adsorbent (F400, $1,125m^2/g-GAC$), which is commonly used, and most of pores were found to be micropores with pore radius of 2nm and below. It was found that RB19 was most easily adsorbed among the dyes in this study. In the case of PCP (p-chlorophenol) and sucrose, which are single component adsorbate, adsorption capacities of ACF(A-15) were in good agreement with the batch adsorption measurement, and saturation time predicted of ACF columns for these components was also well agreed with practically measured time. But in the case of reactive dyes, which have relatively high molecular weight and aggregated with multi-components, adsorption capacities or saturation time predicted were not agreed with practically measured values.