• Journal of Korean Society of Environmental Engineers
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• v.35 no.7
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• pp.509-517
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• 2013

The purpose of this study is to assess the applicability of device-type stream coagulation process which combines physiochemical, biological processing for efficient improvement of water quality in small, middle-sized urban streams. The stream purification facility of this study is compose of pressure flotation type Micro Bubble Process(MBP) to remove TSS and TP and conduit line type Attached Microbial Pipe System(AMPS) to remove BOD. Test conditions of each device were set by floating stay time and change of ultra fine bubble injection amount of MBP, and change of AMPS stay time. Also, removal efficiency of pollution sources of each process were assess by change of season. As result of continuous operation of each process, MBP showed a maximum of TSS 83.69%, TP 95.15% process efficiency and AMPS showed a maximum of 52.95% TBOD5 removal efficiency. Also as result of circular operation of each process, MBP showed a maximum of TSS 69.75%, TP 70.17% process efficiency and AMPS showed a maximum of 68.58% TBOD5 removal efficiency. Therefore, it is considered that this stream coagulation process is effective in improving the water quality of streams in urban areas.

• Journal of Wetlands Research
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• v.12 no.3
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• pp.39-47
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• 2010

Annually, the scale of agricultural areas in Korea were being reduced as the lands were converted to other land uses. While the rate of productivity were either being maintained or increased, the pollution load from these areas were still greater in magnitude. Although the levels of pollutant concentration released in the agricultural watersheds were minimal, the combined quantities mostly from diffuse sources were high. As a consequence, the Ministry of Environment (MOE) in Korea adopted the use of free water surface (FWS) flow constructed wetlands to reduce the pollutant loadings emitted from agricultural watersheds for the improvement of water quality and protection of aquatic ecosystems. In this study, a constructed wetland treating stream water in an agricultural watershed was monitored since April 2009 subsequent to its completion in December 2008. Satisfactory performance was achieved for TSS, BOD and TP with 26%, 28% and 39% pollutant removal rates, respectively. In addition, the effluent water quality was improved and achieved compliance the national water quality criteria. Results of this study can be useful to establish design parameters and employ proper removal techniques of similar natural treatment systems for future implementation in the country.

• Journal of Environmental Impact Assessment
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• v.26 no.6
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• pp.508-523
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• 2017

This study monitored the changes before and after restoration of ecological stream focusing on the places which are applied Sustainable Structured wetland Biotop (SSB) system and ecological Fish-way for restoration of Maeno stream. A total of 11 species and 191 individuals of fishes were founded out which were not verified inhabitation before restoration at SSB wetlands. Especially, it was could identified that micro habitat and healthy Fish-way was created because the restored target species, Microphysogobio yaluensis and Iksookimia koreensis were identified that habitation was monitored in SSB wetland. Amphibian have been restored to a number of Rana nigromaculata found in and around wetlands at the time of the third survey, which is highly active after restoration. Specified endangered species class 1 and natural monuments designated by the Ministry of Environment, Lutra lutra lutra, as a Mammalian, uses the wetlands and ecological Fish-way as habitat areas, and the his habitat is restored. In the case of Flora, vascular plants emerging in the survey area were increased to 7 and 13 species before restoration and 15 and 19 species directly after restoration, and 22 species and 33 species after restoration. Vegetation after restoration was found to be a basic producer of various ecosystems and a plant community that contributes to the purification of water quality such as Phragmites japonica communities. As the result of water quality monitoring, the average of treatment efficiencies were BOD 64.3%, T-N 47.2%, T-P 80.7%. Successful treatment of the nonpoint pullution source, which is a limiting factor to disturb the ecosystem, creatively restored the target species in the water quality class I, II.

• Korean Journal of Ecology and Environment
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• v.47 no.spc
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• pp.1-9
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• 2014

Lake Suwa is a natural lake which is well-known for sightseeing and fisheries. It had suffered severe eutrophication during 1960s and 1970s with the occurrence of cyanobacterial blooms and the extinction of some benthic animals. Since 1980 water quality has been improved due to efforts of local government, scientists, and citizens. Of various methods that were attempted to improve the water quality of Lake Suwa biological methods received much attention, because it can improve the lake ecosystem integrity and fisheries in addition to the water quality. The aim of this paper is to introduce the biological methods for water quality improvement that had been employed in Lake Suwa, Japan, and their contribution to the economic benefit of local residents. Until now a significant restoration of water quality has been achieved, but there are insufficient recovery of the sediment and biota due to anoxic hypolimnion of the lake. This study proposed suspended cage culture of bivalves as a feasible method of water quality improvement. Increased grazing by bivalves will contribute to the improvement of water quality and fisheries production, which will contribute both to the ecological restoration and economy of local residents.

• Proceedings of the Korea Water Resources Association Conference
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• 2008.05a
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• pp.2127-2131
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• 2008

본 연구는 자연생태하에서 지속가능한 태양에너지와 생태계작용에 의한 수질개선기법을 개발하기 위하여 생태연못을 설치하여 수질부하가 발생함에 따라 생태연못에 에너지를 순환시켜 생태적 수질정화 기능을 강화하는데 목적을 두었다. 본 연구에서 생태연못(Eco-Pond) 시스템의 수질개선 원리는 수중(유입수)의 침전, 유기산 생성, 메탄 발효, 호기성 산화, 광합성 산소배출 및 병원균 제거 등을 촉진시키기 위한 목적으로 축산농가 및 마을단위의 축산 및 생활하수 유입부에서 생태연못을 두어 수질을 개선하는 공법 즉, 산화조(Oxidation Pond)에 SolaBee 시스템을 결합한 모델을 제안하였다. 에너지 순환장치를 이용한 수질개선 방안으로는 태양열 연못 내에 물순환장치를 만들어 수체를 효율적으로 순환시키고 공기를 혼합시켜 부영양화가 진행되는 연못이 수질을 자연친화적으로 개선시키도록 하였다. 따라서 연구결과 태양에너지는 다른 자연에너지(풍력 등)에 비해서 에너지 밀도는 낮지만 지역의존성이 적고 그 양이 방대하여 21세기 중요한 에너지원으로 사용가능성을 확인할 수 있었다. 본 연구에서 제시된 에너지 순환구조를 가진 생태연못 시스템은 우리나라 중소규모의 농촌 및 축산농가에 보급 될 수 있는 수질개선 시스템이다.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2000.11a
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• pp.78-80
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• 2000

대전광역시에 분포하는 민방위 비상용 지하수 급수시설은 현재 총 225개소가 확보되어 있고 확보된 수량은 약 51,597톤/일이다. 비상용 지하수 중 정부지원시설은 년간 4회에 걸쳐 수질분석을 실시하고 있다. 1996년∼1999년 사이에 수질분석 내용을 보면 약 36% 정도가 음용수 부적합한 것으로 나타났다. 주요 부적합 항목으로 일반세균, 대장균, 질산성질소, 불소 등이다. 수질분석자료를 근거로 보면 동구와 중구의 구도심권의 수질이 나쁜 상태이고, 도시계획도상 녹지지역이 가장 많은 유성구가 가장 좋은 수질특성을 보인다. 대덕구는 공단지역 등을 중심으로 수질이 저하되어 있고, 서구는 신도시보다는 기존도심지의 지하수의 수질이 저하되어 있음을 보이는데, 이는 대전시 지하수의 수질특성이 토지이용 및 도시발달과 밀접한 관계가 있음을 시사한다. 이러한 대전 지하수의 수질 향상을 위하여, 부적합 판정을 받은 급수시설에 대해서는 정밀한 조사를 통하여 오염물질의 종류와 농도변화, 오염의 원인, 오염물의 확산 등에 대한 정밀조사를 실시한 후, 오염정화를 통한 복구나 폐공처리 조치 또는 관측정으로의 전환 등을 모색하여야 할 것이다. 그리고 표본지역에 대한 양수시험결과 기록된 지하수량과 실제치에서 상당한 차이를 보여주어 비상급수시설에 대한 정확한 1일 적정 채수량을 다시 산정할 필요가 있다.

• Journal of the Korean Society of Groundwater Environment
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• v.4 no.3
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• pp.116-121
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• 1997

Pilot wetland reactor systems to test acid mine drainage treatment efficiencies for metals were designed and operated at the Dalsung mine and surveyed the operating problems. pH and Eh (redox potential) were measured in situ and anayses of Cd, Pb, As, Zn, Cu, Fe, Al and Mn were carried out in the laboratory. Maximum metal removal efficiencies of the reactor containing the rice stalks, the cow manure and limestones were that Cu, Zn, Fe, Cd, Al, Mn and Pb were lowered by 98%, 100%, 99%, 100%, 97%, 61% and 100%, respectively and at that time the pH and Eh of the effluents from the reactor were 6 and about -300 mV. However, the redox potential was raised and removal of metal elements except aluminium was decreased with operation time. It suggests that the reduced condition is very important for the metal removal. During the operation, problems such as scaling in pipes and volume change of the substrate within the reactor occurred, which were preventing the flow of main drainage in pipes and reactor.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.10 no.5
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• pp.58-66
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• 2007

과거 빗물은 토양으로 흡수되어 정화작용을 거쳐 호수나 강으로 유입됨으로써 하천의 수질 오염을 방지할 수 있었으나 개발로 인한 도시의 불투수층 증가로 빗물은 여과없이 도시의 오염물질을 쓸어 내리며 하천으로 유입되어 하천의 수질 오염이 날로 심해지고 범람하는 빗물은 짧은 시간에 도시를 물에 잠기게 한다. 오염물질을 함유한 빗물의 정화 및 빗물 유량 조절을 위한 방안으로 미국에서는 레인 가든의 조성이 활발하게 진행되고 있다. 본 원고에서는 레인 가든의 환경적 의의와 조성방법, 그리고 빗물로부터 하천을 보호하기 위한 미국의 관련 규정을 알아보고 레인 가든의 효과에 대해 검토하고자 한다. 레인 가든은 오염 물질의 하천 유입방지 및 빗물의 저장 역할 외에 도시지역에서 최소 관리로 생물 서식처 역할을 함으로써 생태도시 조성 기술을 한 단계 높이는 방안이 될 것이다.

• Journal of Ocean Engineering and Technology
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• v.20 no.4 s.71
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• pp.58-63
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• 2006

When the costal zone surrounded by a breakwater has a narrow vertical opening, currents in the vicinity of a narrow entrance can result in a jet flow, coinciding with the tide. Such a Tidal-Jet Generator(TJG) can change the water mass distribution and transport processes in the domain of influence of the jet. Also, it can decrease the residual time of them. In the present study, the water purification utilizing tidal jets in the coastal zone over constant bathymetry are estimated numerically, using a finite-difference numerical scheme, named the NS-MAC-TIDE method, which isbased on the fully 3D Navier-stokes(NS) equations. The shear velocity near the inlet of the TJG are predicted from the flow field simulation, and are assessed qualitatively with the development of scouring or sediment that is caused by the change of diffusion or sweeping flowup from the seabed of sediment particles. Finally, through solving a transport equation of concentration, the residual time related on mass transport processes and the flushing mechanism for water purification are investigated.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2004.11a
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• pp.92-92
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• 2004