• Journal of Environmental Impact Assessment
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• v.18 no.5
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• pp.245-256
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• 2009

해사채취 선박에 설치된 월류수 저감장치의 효율성을 파악하기 위하여 월류수 저감장치가 설치된 선박과 설치되지 않은 선박의 작업시 부유사 농도를 관측 비교하였다. 부유사 관측결과 월류수 저감장치가 설치된 선박과 설치되지 않은 선박의 작업시 부유사 농도는 부유사 발생원으로부터 거리가 멀어질수록 감소하는 경향을 보였고, 1km 정점부터 배경농도와 비슷한 농도를 나타내었다. 월류수 저감장치의 사용여부에 따른 부유사 농도를 비교 분석한 결과 부유사의 저감효율은 52.9~65.5%(평균 60.8%)로 조사되었다. 또한 월류수 저감장치의 효율은 중층에서 평균 62.6%로 가장 높은 효율을 보였다. 본 연구의 부유사 관측 결과만으로 월류수 저감장치의 부유사 저감효율을 산정하기에는 다소 무리가 있으나, 관측 결과 나타난 월류수 저감장치의 부유사 저감효과는 비교적 양호한 것으로 조사되었다. 또한 월류수 저감장치는 해사채취시 부유사 저감에 효과적인 방법으로 판단되며, 추후 월류수 저감장치 여과망의 여과효율 등 여러 인자들과의 상호 연관성을 종합적으로 고려하여 해사채취 선박에 설치된 월류수 저감장치의 효율을 도출할 예정이며 해사채취 대상해역의 정기적이고 세밀한 연구가 필요하리라 판단된다.

• Journal of Korean Society of Environmental Engineers
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• v.36 no.10
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• pp.685-690
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• 2014

The treatment of combined sewer overflow (CSO) is one of potential concerns in domestic wastewater treatment in Korea due to the pre-announce of CSO regulations. This work investigated the effects of disinfectant (NaOCl) concentration (0.11 to 4.0 mg $Cl_2/L$), pH (6.5 to 8.0), temperature (15 to $25^{\circ}C$), ammonia (10 to 41 mg N/L), and suspended solids (91 to 271 mg SS/L) on the chlorine disinfection of CSO. The effect of NaOCl concentration on the pseudo-$1^{st}$ order reaction rate for total coliform inactivation was described well with a saturation-type model with the half-velocity constant of 1.212 mg/L. The total coliform inactivation reaction rate decreased with SS and pH, and increased with temperature. Ammonia in the examined range did not affect the disinfection kinetics. A chlorine contact tank with the injection chlorine level of 1 mg $Cl_2/L$ and the hydraulic retention time of 1.25 min is estimated to reduce total coliform from $1{\times}10^5MPN/mL$ to 1,000 MPN/mL at 271 mg SS/L, $15^{\circ}C$, and pH 8.0. Chlorine would be a proper option for the disinfection of CSO.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2017.10a
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• pp.43-43
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• 2017

• Water for future
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• v.54 no.11
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• pp.84-90
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• 2021

• Journal of Korean Society of Water and Wastewater
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• v.24 no.2
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• pp.231-236
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• 2010

A compressible media filtration process with synthetic fiber media was studied for combined sewer overflows (CSOs) treatment. Since the operation performance of fiber media filtration was dependent on the pattern of CSOs, the flow rate of CSOs was investigated and it was characterized by a big fluctuation. Thus, in this study, the fiber media filtration process was tested with wide range of filtration velocity. The removal efficiency was proportion to the increase in compressibility. As the filtration velocity was increased, the treatment efficiency was decreased and consequently leveled off when the velocity exceeded 750 $m^3/m^2$/d. An exponential equation was introduced to express the relationship between the removal efficiency and up-flow velocity. At columm test, six repetition of filtration and backwash cycle did not after the filtering velocity under the constant pressure condition.

• Proceedings of the KAIS Fall Conference
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• 2007.05a
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• pp.116-118
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• 2007

비강우시와 강우시 학장천의 수질은 BOD, COD, T-N, T-P, SS에 대해 각각 $11.0{\sim}31.3mg/L$, $15.6{\sim}31.4mg/L$, $5.762{\sim}15.937mg/L$, $0.918{\sim}1.291mg/L$, $18.1{\sim}31.41mg/L$와 $27.2{\sim}65.11mg/L$, $32.1{\sim}73.2rng/L$, $13.409{\sim}18.051mg/L$, $1.263{\sim}2.282mg/L$, $66.0{\sim}417.9mg/L$로 나타나 학장천은 전형적인 생활하수의 특성을 지녔으며, 강우시 발생되는 초기월류수에 다량의 비점오염물질이 포함됨을 알 수 있었다. 강우시 발생된 월류수의 유량을 측정한 결과 학장천의 유출계수는 $0.61{\sim}0.83$의 범위였고, 초기세척효과는 SS>T-N>COD>BOD>T-P>1 의 순서로 그 정도가 크게 나타났다. 학장천 초기월류수의 유량가중평균농도를 산정한 결과 대부분의 항목에서 청천시의 수질농도보다 높게 나타나 강우에 의한 월류수의 비점오염물질의 유출이 심각함을 알 수 있다.

• Proceedings of the Korea Water Resources Association Conference
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• 2008.05a
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• pp.92-96
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• 2008

최근에 이상기후로 인한 집중호우는 단시간의 높은 강우 강도의 발생을 증가시켜 재해 유발의 측면에서 뿐만 아니라 유역 내 비점오염원이 합류식 관거의 월류수인 CSOs(Combined Sewer Overflows)의 형태로 강우와 함께 유입되어 수질 및 환경을 오염시키는 문제점이 발생한다. 이에 따라 월류수의 유출특성에 대한 정량적인 분석을 통하여 유량 및 수질 등의 오염부하량에 대한 적절한 저감 방안이 요구되고 있는 실정이다. 이에 본 연구에서는 비점오염원의 농도가 상대적으로 높은 도시유역에 강우로 인한 월류수의 유출 특성 변화를 분석함과 동시에 월류수가 하천에 방류되었을 때의 하천에 미치는 영향 분석을 통하여 하천의 효율적인 수질 관리 방안을 제시하고자 한다. 경기도 구리시를 대상유역으로 선정하였으며, 도시 강우-유출 모델인 SWMM을 사용하여 유역의 유출량 및 월류수의 수질 모의를 수행하였으며, 유역의 최종 방류구에 비점오염 저감을 위해 설치된 저류지를 통해 하천으로 배출되는 유출수와의 연계는 미국 환경청에서 개발된 WASP 모델을 적용하여 왕숙천 본류에 대한 월류수 변화가 하천에 미치는 영향을 분석하였다. 저류지 설치 전 후의 하천에 월류수가 미치는 영향을 BOD 농도를 중심으로 비교 분석하였다. 분석 결과 저류지 설치 후 BOD 농도의 저감율은 설치 전 보다 최소 1.9%, 최대 81.2%의 저감 효과가 있는 것으로 분석되었다. 향후 신뢰도 높은 수질모의를 위해서는 월류수 발생시 월류수와 하천의 지속적인 모니터링을 통해 현장 여건을 반영할 수 있는 입력변수의 도출이 매우 중요한 것으로 나타났다.

• Journal of the Korean Society of Hazard Mitigation
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• v.4 no.4 s.15
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• pp.21-26
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• 2004

It is muck important to determine the intercepting capacities as measures for reducing the load of contamination influenced by CSOs during wet weather period. Intercepting and treating the whole rainfalls can be best measured for reducing the contamination load, but it is not desirable in view of scale and preservation of the wastewater treatment facilities. This study analyzed the quantity and quality of the water in the combined sewer by method of changing the type and size of drainage basin and intercepting capacities in rainfalls, estimate the influence the other CSOs at the change of planned intercepted quantity, and compared the degree of contamination load between the combined system and separate system by examining the influence of the other CSOs at the change of planned intercepted quantity.

• Journal of Korean Society of Water and Wastewater
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• v.20 no.2
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• pp.295-302
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• 2006

Over the past decades, a flocculation and/or sedimentation process have been adopted to remove pollutants from CSOs. It has been learned that major factors affecting settlement of pollutants are the particle size distribution, their settling velocities and their specific gravity. It is, therefore, a good idea to analyze the particle size distribution and settleability of CSOs pollutants in order to develop details in designing a process. Discussed in this study are pollutant characteristics of CSOs such as particle size distribution and settleability of pollutants. The power law function is applied and is found to be an effective and reliable index for expressing the particle size distribution of pollutants in CSOs. Based on the regression analysis it is observed that the derived constants of curves representing settling velocity profile are proportional to the initial concentration of particles and to the ${\beta}$-values of power law distributions.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.12
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• pp.1340-1346
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• 2005

A water quality modeling study was performed for Chunggye stream during combined sewer overflow(CSO) period, utilizing the diagnostic system for water management in small watershed, CREEK-1(Cyber River for Environment and Economy in Korea). This system integrated geogaphic information system, data base, landscape ecological model(FRAGSTATS), watershed model(SWMM), water quality model (WASP5), and computer graphic. In this study, the watershed model and water quality model were extensively utilized so as to simulate water qualities and flow in Chunggye stream during wet periods. The Chunggye stream watershed was divided into 18 sub-basins in the watershed model and the stream reach into 11 segments in the water quality model. The watershed model was validated against field measurements of BOD, TN, TP, and flow at the downstream location, where the model results showed a reasonable agreement with the field measurements at all parameters. From this study, it was shown that the stream water quality would change along with elapsed time from rainfall start as well as rainfall intensity. The model results indicated that the water quality would significantly upgrade due to the first flush and high sewage ratio of CSO at the beginning of rainfall event, but become degraded along with the runoff increase due to dilution effect.