• 한국환경과학회지
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• 제31권12호
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• pp.1061-1068
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• 2022

The purpose of this study was to develop a recycling system for ozone off-gas. Although the ozone transmission rate of the injector method differs slightly depending on the ozone injection rate, it reaches approximately 99%, which is very high. During the increase in water inflow to the ozone recycling system from 2 L/min to 10 L/min, the average ozone recycling rate was 99.4% at a 1 ppm ozone injection rate, 98.6% at a 2 ppm ozone injection rate, 98.1% at a 3 ppm ozone injection rate. Ozone treatment facility operating costs can be divided into the costs of pure oxygen production, ozone production, and maintenance. The annual operating costs of ozone treatment facilities in Korea are estimated to be approximately 38.9 billion won. The annual savings are estimated to be approximately 5.8 billion won when the ozone transfer rate of the diffuser method, which is mostly employed in domestic water treatment plants, is 85% and 15% of the ozone is recycled.

• 상하수도학회지
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• 제11권2호
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• pp.94-104
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• 1997

Ozone Treatment is getting a common process in a water treatment plant all over the nation. Especially an advanced water treatment using ozone and biofiltration has been a typical method in the regions where using the Nak-Dong River as a drinking water source. The effectiveness of ozone treatment in a continuous flow contact system was investigated with sand filtered water of the Nak-dong River. Pilot tests of the experiments were performed three times of the year like June, August, and October 1995. Most degradable organics of sand filtered water were oxidized in the first and second contact chamber of the system. Ozone treatment was effective for the removal of UV254 absorbance. However, Noticeable removals of $KMnO_4$ demand and TOC(Total Organic Carbon) were occurred when their concentrations exceeded about 5mg/l. The organics causing $KMnO_4$ demand and TOC were degraded into lower molecular matter in an early stage of the ozone contact in the system. Dissolved oxygen concentration was increased after ozone treatment.

• 한국환경보건학회지
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• 제27권4호
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• pp.93-98
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• 2001

Wastewaters produced in textile industrial processes contain dyes which are not easily amenable to biological treatment. The object of this study is to determine the post-treatment system of biological process for the textile wastewater by comparing three different types of chemical process, which were 1) post-treatment by ozone or UV, 2) post-treatment by coagulation,3) post-treatment by ozone or UV followed by coagulation. In an application ozone or UV as a post-treatment, color was generally decreased with time, however, SCOD removal effect was not that good. When coagulation was used as point-treatment process, the effluent quality was satisfying. Therefore, the application of coagulation process as a post-treatment of biological process would be more desirable than that as a ozone or UV.

• 상하수도학회지
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• 제23권6호
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• pp.763-768
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• 2009

Ozone is a strong oxidant and a powerful disinfectant. In general, it has been used in drinking water treatment during last 100years. Ozone dissolution features are defined by the two categories of ozone contactors, bubble-diffuser and sidestream ozone contactor. Currently, sidestream-injection systems are gaining in popularity but operating cost might be slightly higher. Sidestream ozone system dissolve ozone into a sidestream flow via an injection setup or in the main process flow stream in some sidestream arrangements. The sidestream flow is subsequently mixed with the main process flow stream, which is directed to a reation tank or pipeline for oxidation and disinfection reactions. The purpose of this study is to suggest optimal operating pressure, to figure out the static-mixer effect and to understand the microbubble characteristics of ozone to improve dissolution efficiency.

• 상하수도학회지
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• 제18권2호
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• pp.215-221
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• 2004

Effluent of wastewater treatment plant is to be disinfected to protect drinking water sources. DOF (Dissolved Ozone Flotation) was developed to meet this purpose. DOF was developed by combining DAF system with ozone. DAF system has good floating power with numerous microbubbles, and ozone has strong oxidation capability. And DOF system has good floating power and strong oxidation capability simultaneously. When DOF was applied to secondary wastewater effluent, color of 11CU in raw water which was secondary effluent was reduced to 1CU by the DOF system. Removal rate of other water quality parameters treated by DOF were also higher than that by DAF, which were proved the strength of oxidation capability of ozone. When ozone concentration of 3.3mg/l were applied in DOF system, general aerobic bacteria were reduced to 5CFU/ml from TNTC (Too many Numbers To Count). With the same ozone concentration, total coliform were not detected at all. These figures are under the numbers of drinking water regulation. These microbes were the target parameters of DOF. It was proved that DOF was very effective in disinfection of wastewater treatment plant effluent as well as in removal of color, turbidity, and T-P.

• Advances in environmental research
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• 제4권3호
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• pp.155-172
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• 2015

In this study, a complete set of recirculating cooling water system and the required instruments were built in a semi-industrial-scale and a 50 g/h ozone generation plant and a chlorine system were designed for cooling water treatment. Both chlorination and ozonation treatment methods were studied and the results were analyzed during two 45-days periods. The concentrations of ozone and chlorine in recirculating water were constant at 0.1 mg/lit and 0.6 mg/lit, respectively. In ozone treatment, by increasing the concentration cycle to 33%, the total water consumption decreased by 26% while 11.5% higher energy efficiency achieved thanks to a better elimination of bio-films. In case of Carbon Steel, the corrosion rate reached to 0.012 mm/yr and 0.025 mm/yr for the ozonation and chlorination processes, respectively. Furthermore, consumptions of the anti-corrosion and anti-sedimentation materials in the ozone cooling water treatment were reduced about 60% without using any oxidant and non-oxidant biocides. No significant changes in sediment load were seen in ozonation compared to chlorination. The Chemical Oxygen Demand of the blow-down in ozonation method decreased to one-sixth of that in the chlorination method. Moreover, the soluble iron and water turbidity in the ozonation method were reduced by 97.5% and 70%, respectively. Although no anaerobic bacteria were seen in the cooling water at the proper concentration range of ozone and chlorine, the aerobic bacteria in chlorine and ozone treatment methods were 900 and 200 CFU/ml, respectively. The results showed that the payback time for the ozone treatment is about 2.6 years.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2015년도 추계 학술논문 발표대회
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• pp.34-35
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• 2015

Recently, introduction of Advanced water treatment facilities has been increasing due to serious domestic water pollution. Ozone is a strong oxidizing materials in the advanced water treatment facilities. However, due to such a strong oxidation, Ozone eroded waterproofing/corrosion on the concrete surface and caused performance degradation. Therefore, in this study, permeability experiment of metal spraying system by concrete surface treatment was conducted.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2016년도 추계 학술논문 발표대회
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• pp.50-51
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• 2016

Ozone is a strong oxidizing materials in the advanced water treatment facilities. However, due to such a strong oxidation, Ozone eroded waterproofing/corrosion on the concrete surface and caused performance degradation. Therefore, in this study, permeability experiment of metal spraying system by concrete surface treatment was conducted.

• 대한환경공학회지
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• 제30권7호
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• pp.743-750
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• 2008

본 연구에서는 용존오존부상법(Dissolved Ozone Flotation; DOF)을 이용한 정수처리 효과를 파악하기 위하여 적정 오존 주입 농도와 오존 주입 농도별 처리 특성에 대해서 연구하였으며, 또한 용존공기부상법(Dissolved Air Flotation; DAF) 및 중력식 침전법(Conventional Gravity Sedimentation; CGS)과 DOF의 처리 성능을 비교하였다. 최적 오존 주입 농도를 산정하기 위한 실험에서 최적 오존 주입농도는 2.7 mg/L로 나타났으며, 오존 주입 농도가 증가할수록 탁도 및 KMnO$_4$ 소모량, UV$_{254}$ 흡수도, TOC 등과 같은 제거효율이 낮아지는 것으로 나타났다. DOF와 DAF, CGS의 처리성능을 비교한 결과 오존 주입 농도 2.7 mg/L로 운전한 DOF시스템의 탁도 제거효율은 88.9%, 유기물질 항목의 경우 KMnO$_4$ 소모량은 62.9%, TOC 47%, 그리고 UV$_{254}$ 흡수도 77.3% 그리고 THMFP 제거율의 경우 51.6%로 다른 두 공정보다 높거나 비슷하게 나타났다. 따라서 응집 부상 공정과 오존 산화 공정이 하나의 반응기에서 일어나는 DOF 시스템은 정수처리시설의 소유부지 감소와 기존 CGS 시스템에서 처리가 어려운 조류 및 용존성 유기물질의 제거를 통해 소독부산물의 생성을 감소시킴으로 향후 고도정수처리시스템으로 적용 가능성이 충분한 것으로 판단된다.

• Journal of Advanced Marine Engineering and Technology
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• 제34권3호
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• pp.391-398
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• 2010

This study is currently giving priority to developing the ballast water treatment system using ozone(Ozone BWTS). The Ozone BWTS, were equipped on the real merchant vessel named as M. V. Hyundai Hong Kong to carried out shipboard tests of ballast water treatment system in accordance with orders of IMO G8 Guidelines. The study results show that the Ozone BWTS is capable of meeting the Ballast Water Performance Standard under Regulation D-.2 of the International Convention for the Control and Management of Ships’ Ballast Water and Sediments, and also the more stringent standards being proposed under US legislation.