• 상하수도학회지
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• 제32권2호
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• pp.183-192
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• 2018

Applicability of corrosion inhibitor was evaluated using pilot scale water distribution pipe simulator. Calcium hydroxide was used as corrosion inhibitor and the corrosion indices of the water were investigated. Corrosion indices, Langelier saturation index (LI) increased by 0.8 and calcium carbonate precipitation potential (CCPP) increased by 9.8 mg/L. This indicated that corrosivity of water decreased by corrosion inhibitor and the effects lasted for 18 days. Optimum calcium hydroxide dose was found to be 3~5 mg/L for corrosion inhibition. We suggest that monitoring of CCPP as well as LI need to be conducted to control corrosivity of water.

• 한국환경과학회지
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• 제14권10호
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• pp.937-944
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• 2005

Presently, aquatic plants are used for the water purification in inland water. This study was carried out to investigate the water purification effect of aquatic plants, Oenanthe javanica and Typha angustata, The experiment was conducted in outdoor flowing water was conducted for ten days, Water quality was measured in terms of water temperature, COD(chemical oxygen demand), SS(suspended solids), Total N, Total P. The results of field experimentation showed that hydraulic retention time was the earliest in July and August 2003, and there were not any particular changes of monthly water temperature in inflow water and outflow water. As we look at the changes taken place in inflow water and outflow water throughout the whole experiment period, the change of water quality in summer was salient, especially SS removal ratio showed distinguished change as $25\%$, when the pebble filter and aquatic were attached to it. The removal rate of COD, total N total P were $14,7\%,\;8\%\;and\;9\%$, respectively. In relating the length of water extension to the change in water quality, the water quality tended to get lower generally in proportion to hydraulic retention time.

• 상하수도학회지
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• 제14권4호
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• pp.328-336
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• 2000

In order to compare the effect of water quality on two service systems, tank and direct connection service, we selected randomly 30 rooftop tanks installed in the buildings with five or fewer floors, and collected water samples from each tank as well as tap water by direct service. At the same time each tank was investigated on their cleanliness and sanitary control. 30 water samples from direct service met Korean Drinking water quality standard. But 5 tank water samples(17%) were not able to meet Coliform or Total Colony Counts standard and free chlorine of 12 tank water samples(40%) were less than 0.2mg/L. Also Fe, Turbidity, TOC, Total Algae in tank water were higher than tap water on direct service. We concluded that thorough health control of water tank is necessary and conversion into direct connection service results in improving tap water quality importantly.

• 한국컴퓨터정보학회논문지
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• 제22권11호
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• pp.65-71
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• 2017

An integrated water environment management system is necessary in improving water quality, properly allocating water resources, and supporting socio-economic development. Specifically, water quality management system using web map can be an efficient approach to accomplish this system. This paper aims to construct a dynamic water quality management system to reflect a water environment management system which includes three sub-models with consideration of their interrelationships (a socio-economic model based on dynamic Input-Output model, a water resources cycle model, and a water pollutants flow model). Based on simulation, the model can precisely estimate trends of water utilization, water quality, and economic development under certain management targets, and propose an optimal plan. This study utilized the model to analyze the potential of using reclaimed water to accomplish local water environment management and sustainable development plan while exploring the applicable approaches. This study indicates that the constructed water environment management system can be effective and easily adopted to assess water resources and environment while improving the trade-off between economic and environment development, as well as formulate regional development plan.

• 한국해양공학회지
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• 제15권4호
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• pp.28-37
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• 2001

The water quality in Yongil Bay is getting worse due to the sewage and the waste water from the surrounding industrial complex. The study aims to simulate the current system that is necessary to build ecosystem model for the optium water quality control and clarify the correlation of current system characteristics with water quality in Yongil Bay. To clarify the characteristics of coastal water movement system and verify the applicability of the 3-D model, the current system was simulated using 3-D model baroclinic model which considers tidal current and density effects. As the results of numerical experiments, it is proved the 3-D model is the most applicable on appearing the current system of the stratificated Yongil Bay difference of density. Form the results of simulation considered tidal current only, it can be clarified that the water body flows in the inner bay through the bottom layer and flows out the outer bay through the surface layer in Yongil Bay. And the fresh water from the Hyongsan river and the thermal discharge form POSCO have a little effect on the current system in Yongil Bay, but the diffusion of heat and salt has an important effect upon the formation of the density stratification of the water quality distribution is closely related with the current structure characteristics as well as the tidal residual current system in Yongil Bay.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2000년도 추계학술대회 논문집
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• pp.246-252
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• 2000

The water quality in Yeongil Bay is getting worse due to the sewage and the waste water from the surrounding industrial complex The study aims to simulate the current system that is necessary to built ecosystem model for the optium water quality control and clarify the correlation of current system characteristics with water quality in Yongil Bay. To clarify the characteristics of coastal water movement system and verify the applicability of the 3-D model, the current system was simulated using 3-D baroclinic model considered tidal current and density effects. As the results of numerical experiments, it is proved the 3-D model is the most appliable on the Yongil Bay where current flows slowly and the flow direction is varied by depths. From the results of simulation considered tidal current only, It am be clearly said the water in Yongil Bay flows in through the surface layer and flows out through the bottom layer. And the fresh water from the Hyongsan river and the heated discharge from POSCO have little effect on the current structure in Yonggil Bay, but have and important effect upon the density structure by diffusion of heat and salt. And the water quality distribution is closely related with the current structure characteristics as well as the tidal residual current system.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2010년도 학술발표회
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• pp.452-456
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• 2010

Water is an indispensable input to human's existence and industrial production. In these days, people are getting more concerned about their health and the interest in the safety of drinking water has increased. In this situation, this paper attempts to measure the economic benefits of the tap water quality improvement. The study area was restricted to Busan, the second largest city in Korea, where local government is planning to implement a tap water quality improvement program. We apply a one-and-one-half bounded dichotomous choice contingent valuation (CV) method to obtain at least a preliminary evaluation of the benefits. CV is developed for valuing goods or services that cannot be valued either directly or indirectly from market observations and has been applied to several environmental goods. The CV survey was rigorously designed to comply with the guidelines for best-practiced CV studies. We surveyed a randomly selected sample of 400 households in Busan and asked respondents questions in person-to-person interviews about how they would be willing to pay for the water quality improvement. Respondents overall accepted the contingent market and were willing to contribute a significant amount (US$1.66), on average, per household per month. We can also calculate the aggregate value of the program which improves the water quality in Busan. This study is expected to provide policy-makers with useful information for evaluating and planning environmental policies relating specifically to water.

• 한국토양비료학회지
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• 제48권5호
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• pp.379-383
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• 2015

Indicators of environmental conditions describe the state of the environment and the quantity and quality of natural resources. This study deduced the evaluation items to assess each sub-indicator for agricultural water quality and conducted the surveying using the Delphi method based on agricultural water quality experts. Considering its importance, environmental, state, and management indicators showed that state indicator such as COD concentration for surface water and $NO_3-N$ concentration for groundwater was ranked as first and followed by amount of fertilizer. Its indicators were correlated with state and environmental indicators in surface water and groundwater. The best management indicators were calculated to assess the agricultural surface water and ground water quality. The indicator could be used in established policies for management and conservation of water resources.

• 한국산학기술학회논문지
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• 제12권3호
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• pp.1465-1472
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• 2011

평택호의 수질개선 대책을 수립하기 위하여 호수 내 수질조사를 2회 수행하였으며, 상류 유역의 부하량 삭감에 따른 호소 내 수질개선 효과를 파악하기 위하여 WASP/EUTRO5 모형을 사용하여 시뮬레이션 하였다. 현재의 부하량이 장래에도 지속이 되는 경우에는 호소 내 수질이 상류 유역의 개발에 따른 오염부하량의 증가로 수질이 더욱 더 악화되는 것으로 나타났다. 이에 본 연구에서는 다양한 부하량 삭감 대책을 수립하여 장래의 수질을 예측하였으며, 대안 6가 다른 대안에 비하여 호소의 수질농도를 낮추는 데 크게 기여하는 것으로 나타났다. 그러나, 대안 6의 경우에도 2016년에 호소 내 COD 농도가 9.74 mg/L로 호소수질환경기준 약간 나쁨(4등급, COD 8 mg/L 이하)에도 미치지 못하는 것으로 나타났으며, 2021년에도 유사한 경향을 나타내었다. 대안 6에 부하량을 추가로 삭감하여도 호소의 수질개선 효과는 미미하며 경제적인 측면에서도 적합하지 않은 것으로 나타났다.

• 한국습지학회지
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• 제19권3호
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• pp.287-295
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• 2017

본 연구에서는 금호강의 수질 및 유량 자료를 이용하여 첨두수질에 따른 강우유출 특성을 분석하고 모니터링 및 오염원별 관리 시기 등의 비점오염 관리 방향을 도출하였다. 첨두수질농도(Peak Water Quality Concentration)는 강우유출수내 수질이 가장 높은 농도로 비점오염 관리 기준농도로 극값(Extremal value)을 활용하는 개념이다. 이 방법을 이용하여 누적강수량(총강수량), 첨두수질농도, 첨두수질농도까지의 누적강수량, 첨두수질농도까지의 시간, 첨두수질농도까지의 EMC 등의 평가인자를 검토하였고 장기간에 걸친 실측자료를 이용하여 비점오염원 강우유출특성을 분석하였다. 분석 결과를 통해 비점오염원을 관리하기 위한 적정 모니터링 및 관리방안을 제시하였다.