• 상하수도학회지
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• 제33권1호
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• pp.63-77
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• 2019

Traditional wastewater research mainly focuses on 1) estimating the amount of waste entering sewage treatment facilities, 2) evaluating the treatment efficiency of sewage facilities, 3) investigating the role of sewage treatment effluent as a point source, and 4) designing and managing sewage treatment facilities. However, since wastewater contains a variety of chemical and biological substances due to the discharge of human excreta and material used for daily living into it, the collective constituents of wastewater are likely a reflection of a community's status. Wastewater-based epidemiology (WBE), an emerging and promising field of study that involves the analysis of substances in wastewater, can be applied to monitor the state of a defined community. WBE provides opportunities for exploiting indicators in wastewater to fulfill various objectives. The data analyzed under WBE are those pertaining to selected natural and anthropogenic substances in wastewater that are a result of the discharge of metabolic excreta, illicit or legal drugs, and infectious pathogens into the wastewater. This paper reviews recent progress in WBE and addresses current challenges in the field. It primarily discusses several representative applications including the investigation of drug consumption across different communities and the management of community disease and health. Finally, it summarizes established indicators for WBE.

• 상하수도학회지
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• 제19권5호
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• pp.619-624
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• 2005

This work is for examining a simplified equation based on the rational formula, which can easily decide storm-water detention volume in small urban catchments. The storm-water detention volume is determined by the inflow hydrograph flowing to detention basin and the outflow hydrograph discharged from the detention basin. The ratio of average outflow over the period of rainfall duration against allowable discharge was 0.5 in former simplified equation. But this research has found that the average outflow ratio depends on the storage methodology. In the case of the on-line storage method, the average outflow ratio is a function of the time of concentration of the catchments and rainfall duration, which ranged from 0.5~1.0. In the case of the off-line storage method, the average ratio is a function of peak discharge and allowable discharge except above time of concentration and rainfall duration, where its function value ranged from 1.0~2.0. When applying this equation to small catchment in Mokpo city, South Korea, we could easily calculate the relation curve between the storm-water detention volume and allowable discharge.

• 상하수도학회지
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• 제30권2호
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• pp.147-154
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• 2016

The present study used the hydrodynamic numerical model, with the Reynolds-averaged Navier-Stokes equations (RANS) as its governing equations, to analyze overflow characteristics such as the discharge coefficient of circular-crested weir and the flow velocity and pressure distribution of weir crest. The simulation results well reproduced the overflow characteristics of the overfall of circular-crested weir both qualitatively and quantitatively. As for the discharge coefficient, rational results were yielded by the discharge coefficient equation proposed by Hager(1985) in the $H_1/R_b<0.58$ and by the discharge coefficient equation proposed by Samani and Bagheri(2014) in the $H_1/R_b>0.58$, respectively. Because most existing discharge coefficient equations were developed by disregarding the effects of the approach velocity, when they are applied, it is necessary to evaluate the effects of the approach velocity on the overflow head beforehand.

• 상하수도학회지
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• 제27권2호
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• pp.177-184
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• 2013

This study analyzed the hydraulic characteristics of a venturi flume with a circular cone using a 3-D numerical model which uses RANS(Reynolds-Averaged Navier-Stokes Equation) as the governing equation. The venturi flume with the circular cone efficiently measures the discharge in the low-flow to high-flow range and offers the advantage of accurate discharge measurements in the case of a low flow. With no influence of the tail-water depth, the stage-discharge relationship and the flow behaviors were analyzed to verify the numerical simulation results. Additionally, this study reviewed the effect of the tail-water depth on the flow. The stage-discharge relationship resulting from a numerical simulation in the absence of an effect by the tail-water depth showed a maximum margin of error of 4 % in comparison to the result of a hydraulic experiment. The simulation results reproduced the overall flow behaviors observed in the hydraulic experiment well. The flow starts to become influenced by the tail-water depth when the ratio of the tail-water depth to the total head exceeds approximately 0.7. As the ratio increases, the effect on the flow tends to grow dramatically. As shown in this study, a numerical simulation is effective for identifying the stage-discharge relationship of a venturi flume with various types of venturi bodies, including a venturi flume with a circular cone.

• 한국막학회:학술대회논문집
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• 한국막학회 2004년도 Proceedings of the second conference of aseanian membrane society
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• pp.117-120
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• 2004

The separation characteristics were investigated with the variations of pressure and temperature using ultrafiltration and reverse osmosis membrane module sets composed of different membrane types and materials. TDS, T-N and COD removal efficiencies were not affected and low with the change of temperature and pressure in case of using UF modules contained in module set 1, 2, 3. TDS, T-N and COD removal efficiencies were very high in RO modules. The final water quality of acrylic wastewater was satisfied within the discharge limit value of plant wastewater. It was known that membrane module sets could be used for the reuse of wastewater.

• 해양안보
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• 제2권1호
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• pp.125-149
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• 2021

후쿠시마 원전 사고가 일어난 지 10년이 지난 지금까지도 일본은 매일 생성되는 원전 오염수 문제를 해결하지 못하고 있다. 그들은 오염수 저장탱크가 한계에 다다를 것으로 예상되자, 안전성에 관한 한국의 우려에도 일방적으로 원전 오염수를 해양에 방출하기로 했다. 문제는 한국의 대응에도 불구하고, 여전히 일본이 『유엔해양법협약』상 의무를 성실히 이행하지 않은 채 해양 방출을 준비하고 있다는 데 있다. 원전 오염수의 방사성물질로 인한 해양오염은 물론, 한국의 해양주권 침탈까지도 우려되는 상황이다. 특히 한번 환경이 오염되기 시작하면 본래의 상태로 되돌리기 어렵기에, 당장 안전성이 보장되지 않는 한 원전 오염수의 해양 방출은 반드시 막아야 한다. 본 논문은 일본과 한국이 원전 오염수 해양 방출 사안으로 빚은 갈등을 해결하기 위한 한국의 대응 전략을 제안한다. 한국은 일본과의 협력, 잠정조치, 주변국과의 공조를 통해 다양한 측면에서 일본의 원전 오염수 해양 방출에 대응해야 할 것이다.

• 한국항해항만학회지
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• 제29권9호
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• pp.783-788
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• 2005

This study provided the status and efficiency of the domestic wastewater sea outfalls based on the previous numerical and experimental studies for the analysis of the buoyant discharges from Rosette diffuser in shallow water. The VISJET model and the hybrid model proposed by Kim (2002) can be proper models for the domestic sea outfalls. The experimental results show that the merging height for MBR and MIR depends on the riser diameter and spacing between risers, and the bending characteristics of the buoyant discharges in still ambient water have significant impacts on the dilution. The current wastewater outfall systems in Korea are not effective for the environmental aspect due to the low discharge water depth. The strategies to reduce the contamination near the domestic wastewater outfalls were found to require the sufficient discharge water depth, proper diffuser location considering the tidal currents, enough riser diameter, and sufficient spacing between risers.

• 한국해양환경ㆍ에너지학회지
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• 제1권2호
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• pp.60-70
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• 1998

국내에서 가장 전형적인 폐쇄성 해역인 마산만은 연안도시인 마산시와 창원시의 배수지역이다. 유역인구가 약 100만명으로 증가된 시점인 1993년 11월에 마산시 덕동하폐수종말처리장이 가동되기 시작하였으며, 그 유출수는 마산내만에서 약 15km 떨어진 옥계해역에 방류되기 시작하였다. 본 연구에서는 마산만 유입부하의 분포가 어떻게 변화하였으며, 유입부하량과 유입오염물질의 성상은 어떠한 가를 규명하였다. 또한 마산만 유입부하 특성의 변화가 폐쇄성 연안 수질에 어떠한 영향을 주고 있는가를 연구하였다.

• 상하수도학회지
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• 제33권2호
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• pp.151-158
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• 2019

Objectives of this study were to identify the hotspot for displacement of the on-line water quality sensors, in order to detect illicit discharge of untreated wastewater. A total of twenty-six water quality parameters were measured in sewer networks of the industrial complex located in Daejeon city as a test-bed site of this study. For the water qualities measured on a daily basis by 2-hour interval, the self-organizing maps(SOMs), one of the artificial neural networks(ANNs), were applied to classify the catchments to the clusters in accordance with patterns of water qualities discharged, and to determine the hotspot for priority sensor allocation in the study. The results revealed that the catchments were classified into four clusters in terms of extent of water qualities, in which the grouping were validated by the Euclidean distance and Davies-Bouldin index. Of the on-line sensors, total organic carbon(TOC) sensor, selected to be suitable for organic pollutants monitoring, would be effective to be allocated in D and a part of E catchments. Pb sensor, of heavy metals, would be suitable to be displaced in A and a part of B catchments.

• 상하수도학회지
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• 제20권1호
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• pp.79-85
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• 2006

Innovated technique to oxidize pollutants has been developed. The technique for this study uses plasma discharge in 2-phase (Air-Water) and is called Discharged Water Generating (DWG) system. It produces electric arc which generates not only the physical decomposing power against the pollutants but also oxidants to sterilize pollutants depending on the inlet gas species. These physical and chemical products play an important role in COD decrease and biodegradability enhancement. The enhancement of biodegradability for the refractory organic substances in aqueous solution was estimated in this study. Argon discharge reduced NBDCOD of EDTA from 58.7mg/L to 38.8mg/L, but oxygen discharge and ozonation reduced it to 37.74mg/L and 38.73mg/L respectively. Furthermore, Argon discharge changed 1181mg/L of NBDCOD of dye effluent into 606mg/L but oxygen discharge and ozonation changed it into 888mg/L and 790mg/L respectively.