• 한국물환경학회지
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• 제21권6호
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• pp.659-663
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• 2005

Many studies have been conducted to develop new technologies for arsenic removal and to reveal the levels of arsenic and other chemicals in rivers, lakes and ground waters. However, there are few studies dealing with such compounds in the total water system of the city, and the way of management of these compounds in the water system. Because the occurrence of these hazardous compounds, which are geological origins, is almost impossible to control, it is very important to manage these compounds in the water system. In this research, it was revealed that the risk of arsenic in the water treatment system of S city in Japan. As a results, the parameters such as Q in river and E260 in drinking water treatment plant is proposed as a new indicator with simple and rapid method for controling arsenic level.

• 생명과학회지
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• 제15권5호
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• pp.696-702
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• 2005

오존처리는 음용수중의 유해한 미생물을 소독하는 처리기술로 주로 이용되고 있으며, 생물활성탄 처리기술 역시 오염물질 제거를 포함한 음용수 제조과정에 여러 가지 이점을 제공한다. 이글의 병행처리는 원수중의 여러 물질을 제거하는데 효과적인 공정으로 간주되고 있다. 본 연구에서는 낙동강 하류의 매리취수장 원수를 사용하여 생물활성탄 정수처리공정 및 오존에 의한 수질 변화와 함께 폴리오바이러스 제거 효율을 조사하였다. 수질인자들은 BAC 여과를 거치면서 $NH^{+}_{4}-N$등을 포함한 모든 항목들은 거의 제거되는 것으로 나타났다. Pilot-plant를 이용한 정수처리공정별 폴리오바이러스 제거실험에서는 전오존 접촉에 의해 $96.8\%$, 침전단계에서$99.3\%$, 여과단계에서 $99.6\%$의 바이러스가 제거되었으며, 후오존을 거친 BAC 여과수 시료에서는 세포배양법과 ICC-PCR 방법에서 바이러스가 $100\%$ 제거되어짐을 확인할 수 있었다. 오존농도에 의한 폴리오바이러스 제거실험 결과 0.4mg/1에서 5분간 접촉되었을 때는 약 $61.1\%$ 이상이, 0.8mg/1에서 10분 이상 접촉시킨 후에는 바이러스의 $100\% $가 불활성화 되어졌음을 알 수 있었다.

• 한국물환경학회지
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• 제38권5호
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• pp.231-239
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• 2022

In this study, we applied ENERWATER to evaluate the energy consumption labeling of wastewater treatment plants in Korea using the Korea sewerage statistics data. The results showed that the energy label status was excellent in the SBR process for small and medium-scale wastewater treatment plants and the A2O process for large-scale wastewater treatment plants. The energy labeling of wastewater treatment plants of 50,000 tons capacity was excellent. The statuses of metropolitan cities and Jeollanam-do province were excellent. We analyzed the effects of renewable energy on wastewater treatment plants' energy consumption and found out that digestion gas for large-scale plants and photovoltaic energy for small-scale plants were effective in improving energy labeling. In addition, we compared the energy labels of four wastewater treatment plants in "Z" city and wastewater treatment plant "X" had the best energy label, and the wastewater treatment plants "V" and "Y" had to be selected as priorities for the energy diagnosis and improvement project. In a comprehensive conclusion, the applicability of ENERWATER was confirmed based on sewage statistics data and labeling can be used to set priorities for the energy diagnosis and improvement project.

• 상하수도학회지
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• 제31권5호
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• pp.415-419
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• 2017

In recent years there have been large increases in the hydraulic loading rates used to design dissolved air flotation (DAF) facilities for drinking water applications. High rate DAF processes are now available at loading rates of 20 to $40m^3/m^2{\cdot}h$. This research evaluated dissolved air flotation as a separation method for algae and organic compounds from water treatment plants. During the service period of 2016. 5. to 2017. 6., DAF pilot plants ($500m^3/day$) process has shown a constantly sound performance for the treatment of raw water, yielding a significantly low level of turbidity (DAF treated water, 0.21~1.56 NTU). As a result of analyzing the algae cell counts in the influent source, it was expressed at 100-120 cells/mL. In DAF treated water, the removal efficient of alge cell counts was found to be upto 90%. The stable turbidity and algae removal were confirmed by operating the high rate DAF process under the condition of the surface loading rate of $30m^3/m^2{\cdot}hr$.

• 대한환경공학회지
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• 제37권9호
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• pp.517-525
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• 2015

대전 3대 하천의 1992년 1월부터 2014년 12월까지 수질변화 추이를 분석하고, 대전하수처리장의 방류수가 갑천의 수질환경에 미치는 영향을 분석하였다. 2014년 대전의 갑천3 지점의 BOD, COD, TN, TP 연평균 농도는 각각 1.53, 3.36, 2.16, 0.03 mg/L로서 우리나라 하천수질기준으로 Ib 급수의 수준을 나타내나, 하수처리장 방류수가 유입된 이후 금강으로 유입되기 직전 지점인 갑천A 지점에서는 각각 3.43, 11.51, 8.62, 0.12 mg/L 수준으로써 COD는 매우 나쁜 수준인 VI 급수의 수준에해당하며 BOD와 TP는 III 급수의 수준을 나타낸다. 대전하수처리장이 가동을 시작한 1994년 이전의 수질에 비하여 고도처리 시설이 완공된 2013년 이후의 수질을 비교하였을 경우, 전체적으로 수질이 개선되었으나, 갑천 최상류 봉곡교 지점 및 최하류 지점의 TN농도는 각각 2배 및 3배가량 증가한 것으로 조사되었다. 갑천 최하류의 수질에 기여하는 오염부하량 분포를 산정한 결과 대전의 하수처리장 방류수가 TN, TP, BOD와 COD 총부하량의 각각 76%, 63%, 35% 및 46%를 차자하는 것으로 나타났다. 따라서 금강의 수질을 개선하기 위한 갑천의 수질관리는 TN 및 TP 등 영양염류는 하수처리장의 방류수를 추가 개선하는 것이 바람직한 것으로 판단되며, BOD 및 COD를 포함하는 유기물은 하수처리장 방류수의 오염부하와 함께 위 부하량의 각각 54% 및 47%를 차지하는 각종 소하천 및 우수거등 비점오염원에서 유입되는 부하량을 함께 관리해야 할 필요성이 있다고 분석된다.

• 한국물환경학회지
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• 제33권5호
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• pp.580-586
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• 2017

The fractionation characteristics of organic matter were investigated in inflow and effluent of each other pollution sources and river. While the DOC/TOC ratio in the influent of public sewage treatment plant and livestock disposal facilities was above 0.58, the POC/TOC ratio of human livestock Night soil treatment plant and stormwater runoff was more than 0.7. The TOC removal efficiency of public sewage treatment plant and human livestock Night soil treatment plant were 88.5 % and 99.6 %, respectively. Although the concentration distribution of organic matter pollution most of total organic carbon (TOC) in effluent of pollution sources accounted for dissolved organic carbon (DOC) type (DOC/TOC ratio >0.89) and Refractory-DOC (RDOC)/TOC ratio was higher (>0.65). The fractionation characteristics of organic matter in river were similar with that of sewage treatment plant and TOC concentration showed the positive correlation with DOC ($r^2=0.93$) and RDOC ($r^2=0.89$) concentration. The decay rate of Labile DOC (LDOC) (avg. $0.128day^{-1}$) was higher than labile particulate organic carbon (LPOC) ($0.082day^{-1}$), while that of DOC ($0.008day^{-1}$) was lower than POC ($0.039day^{-1}$) (paired t-test, p < 0.001, n = 5). These study results suggested that it should consider important both TOC and DOC as the target indicator to control refractory organic matter in pollution sources.

• 한국농공학회지
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• 제45권2호
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• pp.126-137
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• 2003

The feasibility study of UV-disinfection system was performed for disinfection of effluent from wastewater treatment plant. Three low-pressure UV lamps of 17, 25, and 41 W were examined with various flow rates. Low-pressure UV lamps of 17W were examined with various turbidity, DOM (dissolved organic matter), and SS (suspended solid). The pilot plant was a flow-through type UV-disinfection system, and the range of exposure time varied from 5 to 40 seconds, turbidity from 0 to 40 NTU, DOM from 0 to 30 mg/L, and SS from 10 to 40 mg/L. The 41W lamp demonstrated complete disinfection showing no survival ratio in all the experimental conditions, and generally 17W and 25W lamps also showed high removal ratio over 97%. For the same UV dose (UV intensity times exposure time), high intensity-short exposure conditions showed better disinfection efficiency than low intensity-long exposure conditions. While the effects of turbidity and DOM were not apparent, the effects of SS was significant on the disinfection efficiency which indicates that SS control before UV-disinfection appears to be necessary to increase removal efficiency. Considering characteristics of effluent from existing wastewater treatment plants, cost-effectiveness, stable performance, and minimum maintenance, the flow-through type UV-disinfection system with high intensity and low-pressure lamps was thought to be a competitive disinfection system for wastewater reclamation.

• 한국물환경학회지
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• 제25권5호
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• pp.764-767
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• 2009

For a more effectively designed gravity thickener, thickening experiments were conducted for residuals produced by a ceramic membrane water treatment plant (WTP). Two kinds of residuals, one from backwashing (BW) and the other from chemically enhanced backwashing (CEB) procedure, were separately collected during a pilot plant experiment and their limiting solid flux ($SF_L$) measured. Batch thickening experiments showed that the BW and CEB residual had $SF_L$ of 10 and $25kg/m^2{\cdot}d$, respectively. Continuous operation of a pilot-scale gravity thickener proved that a mixed BW and CEB residual could be successfully thickened at the solid loading rate (SLR) of $12kg/m^2{\cdot}d$, allowing the concentration of the thickened residual to be about $15kg/m^2{\cdot}d$. From the experimental results and consideration of the seasonal thickening characteristics of the residual, SLR of $15kg/m^2{\cdot}d$ was proposed as a design parameter for full-scale gravity thickeners.

• 한국물환경학회지
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• 제37권1호
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• pp.47-54
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• 2021

Aerobic granular sludge (AGS) can be classified as a type of self-immobilized microbial aggregates measuring more than 0.2 mm. It offers the option to simultaneously remove COD, N, and P that occur in different zones inside a granule. Also, AGS is characterized by high precipitability, treatability with high organic loading, and high tolerance to low temperature. In this study, a sequencing batch reactor inoculated with AGS (AGS-SBR) is a new advanced wastewater treatment process that was proven to grow AGS with integrated nutrient removal and low C/N ratio. A pilot plant, AGS-SBR with a capacity of 225 ㎥/d was installed at an S sewage treatment plant in Gyeonggi-do. The results of the operation showed that the water quality of the effluent indicated that the value of BOD5 was 1.5 mg/L, CODMn was 11.4 mg/L, SS was 6.2 mg/L, T-N was 13.2 mg/L, and T-P was 0.197 mg/L, and all of these values reliably satisfied an effluent standard (I Area). In winter, the T-N treatment efficiency at a lower temperature of less than 11℃ also showed reliability to meet the effluent standard of the I Area (20 mg/L or less). Analysis of microbial community in AGS showed a higher preponderance of beneficial microorganisms involved in denitrification and phosphorus accumulation compared with activated sludge. The power consumption and sludge disposal cost were reduced by 34.7% and 54.9%, respectively, compared to the domestic SBR type sewage treatment plant with a processing capacity of 1,000 ㎥/d or less.

• 한국환경과학회지
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• 제11권4호
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• pp.355-360
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• 2002

This study was to analyze the right of wrong of gray-water treatment by applying BPBE electrode cell to the effluence water in the terminal disposal plant of sewage. The results were as follows : The best result was obtained with applied voltage 40V and detention time 6 minutes for the BPBE electrode cell which has the graphite-plate in main electro-de, packing coconut activated carbon. The elimination rate of COD of Al-plate was higher than that of graphite-plate in main electrode. The result of electrolysis for 3 hour in parallel circuit showed the using possibility of gray-water according to each elimination rate : COD 59%, T-N 69 %, T-P 69%. The BPBE electrode cell with the Al-plate in main electrode made the best effect for the elimination of algae in lake water and algae were not occurred in electrolytic water.