• 대한토목학회논문집
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• 제29권5B호
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• pp.419-427
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• 2009

기존의 WTP를 이용한 수질개선 관련 편익산정 연구들은 특정 하천에 대하여 '모든 종류의 물놀이 가능한 2급수로 개선', '수영가능수준으로 개선' 등을 설문대상으로 하여 지불의사를 산정한 다음, 해당 유역의 가구수를 곱하여 편익으로 산정하였다. 이는 특정 수자원개발사업에 대한 편익이 아니며, 설문작성 과정에서 수질개선 정도에 대한 객관적인 설명이 부족하고, 단순화되었기 때문에 설문응답자들에게 설문대상재화에 대한 정보를 전달하는데 미흡한 점이 있었다. 따라서 본 연구에서는 수자원개발사업시 상수도 원수수질개선에 대한 편익/비용분석에 적용할 수 있는 편익산정방법론을 제시하였다. 본 연구에서는 수도권을 대상으로 하여 용수를 사용하는 소비자의 BOD 개선정도별 지불의사(WTP)를 설문을 조사하고, 설문결과를 통계분석하여 수질개선-지불의사 관계식을 도출하였다. 사례연구로서 낙동강수계의 내성천 지방2급하천 구간에 계획한 송리원 다목적댐을 대상으로 적용하였다. 방류시나리오별 연평균편익산정 결과, 연평균계획방류량($4.79m^3/s$) 방류시 5,980 백만원, 풍수기(7~10월)를 제외한 기간의 계획방류량($7.22m^3/s$) 방류시 8,663 백만원, 수질악화기 계획방류량($10.72m^3/s$) 방류시 11,905 백만원, 최대계획방류량($13.54m^3/s$) 방류시 14,502 백만원으로 산정되었다. 본 연구에서 개발된 가구소득별 수질개선 (BOD)-지불의사(WTP) 관계식을 이용함으로써 수질개선사업에 대한 원수수질편익을 산정할 때 수질개선정도에 상관없이 쉽게 편익을 산정할 수 있을 것으로 판단된다.

• 해양환경안전학회지
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• 제23권5호
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• pp.524-531
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• 2017

본 연구는 생태계 모델을 이용하여 부산연안으로 유입되는 부하량 삭감에 따른 해역의 수질개선 정도를 예측하였다. 모델링 결과에 의하면 COD, T-N, T-P 모두 수영만 연안과 낙동강 하구에서 뚜렷한 개선을 나타냈으며, 수영만을 제외한 만 중부에서 만 동쪽까지는 수질개선이 거의 나타나지 않았다. 이는, 부산연안이 남해에 위치한 다른 해역에 비해 개방형경계를 가지고 있어서, 물질교환이 빠르기 때문으로 판단된다. 수질개선을 위한 본 해역의 삭감 COD 부하량은 타 해역에 비해 적었고, 총 유입부하량에 대한 삭감비율 또한 작게 나타났다. 본 연구에 적용한 부하삭감량을 적용하면 수영만, 낙동강 하구부근에서 뚜렷한 수질개선효과를 얻을 수 있을 것으로 판단된다.

• Water Engineering Research
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• 제6권4호
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• pp.161-168
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• 2005

With characteristics of river continuum, stream ecosystems have diverse components and environments from upstream channel to estuarine area. Therefore, the habitat requirements and composition of conservative object should be well understood before applying any improvement measure. In this paper, the causes of stream habitat changes were first illustrated with the categories and principles of habitat restoration methods. The structural restoration techniques of fish habitat improvement utilized by the authors or one three-year research project starting at 1990 were then presented. Through the introductions on the project background, planning guidelines, structure design, and ecological evaluation, this paper tried to provide some effective examples of stream restoration practices that ecological expert was invited for cooperation and advising.

• 한국환경복원기술학회지
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• 제4권1호
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• pp.90-97
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• 2001

For improvement of water quality, $20m^2$ of artificial floating plant islands planted with Iris pseudoacorus, were installed in small pond on March, 1999. Small pond has surface area $1,000m^2$ and mean depth 1.5 m. The density of plants was 16 per $m^2$ by using jute pot. Environmental parameters such as COD, SS, T-N, T-P and planktons were biweekly measured from 29 March to 28 September. Because of the small portion of floating island, the effect for water quality improvement was not sufficient. But considering the data of plant growth and nitrogen and phosphorus uptake capacity of plant, about 40% of coverage by artificial floating island was needed for elimination of whole nutrients from inflow.

• 한국환경과학회지
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• 제17권1호
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• pp.113-118
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• 2008

[ $6{\sim}13mg/L$ ] base water concentration on monthly BOD has been kept at the Geukrak bridge point for this research target and it indicates the water quality under the existed rank. Due to this present condition of water quality, the demage of ecology from the upper stream to the lower one of the bridge could be conjectured. Moreover, nonstructural extinction of the ecology seems to have gotten worse between both the streams of Yeoungsan River. On this research, eco-corridor between the upper stream and the lower stream of the river should be ensured, the ecological demage needs to be cut off, a dispersed discharge method which the existed method of the 1st sewage plant in Gwangju was enhanced to should be inducted for the procuring of various water ecosystem, and the conditions by the scenario suggested from this research could be applied to a water quality model. then, analysis the improvement effect of the water quality adjacent the river. From the test result, Case3-Type1 scenario is thought to be the best one. From the test result with Case3-Type1 when the concentrated discharge was never done, 0.07 mg/L of BOD concentration was increased at the lower stream where Yeoungbon B point (Haksan Bridge) is but the water improvement effect of $0.24{\sim}2.87mg/L$ is thought to have been done at the area of water deterioration.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2022년도 학술발표회
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• pp.475-475
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• 2022

The aim of this study is to identify the significant pollutant sources from the tributaries that are affecting the water quality of the study site, the Geum River and provide a solution to enhance the water quality. Multivariate statistical analysis modles such as cluster analysis, Principal component analysis (PCA) and positive matrix factorization (PMF) were applied to identify and prioritize the major pollutant sources of the two major tributaries, Gab-cheon and Miho-cheon, of the Geum River. PCA identifies three major pollutant sources for Gab-cheon and Miho-cheon, respectively. For Gab-cheon, wastewater treatment plant (WWTP), urban, and agricultural pollutions are identified as major pollutant sources. For Miho-cheon, agricultural, urban, and forest land are identified as major pollutant sources. On the contrary, PMF identifies three pollutant sources in Gab-cheon, same as PCA result and two pollutant sources in Miho-cheon. Water quality control scenarios are formulated and improvement of water quality in the river locations are simulated and analyzed with the Environmental Fluid Dynamic Code (EFDC) model. Scenario results were evaluated using a water quality index developed by Canadian Council of Ministers of the Environment. PCA and PMF appears to be effective to identify water pollution sources for the Geum river and also its tributaries in detail and thus can be used for the development of water quality improvement alternative of the above water bodies.

• 상하수도학회지
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• 제28권5호
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• pp.609-614
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• 2014

Researcher of this study improved conventional circle secondary settling basin, through the way such as extend of inlet pipe length, introduction of device for inducting uniforming of flow, keeping of height of sludge interface. Also, we compared conventional circle settling basin to improved circle settling basin the water treatment efficiency. Result of research, when SVI is average 117, improvement rate of SS and BOD were 51.0%, 37.0% approximately compared to conventional settling basin. And when SVI is average 178, improvement rate of SS and BOD were 22.7%, 36.0% approximately. Also when SVI is average 196, improvement rate of SS and BOD were 24.7%, 30.3% approximately. When it's winter, improvement rate of SS, BOD, COD, TN and TP were 20.6%, 17.9%, 13.9%, 13.5%, 12.4% approximately. Therefore, we can be the judge, this improved settling basin can be used as the final settling basin in the waste water treatment plant.

• 대한토목학회논문집
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• 제26권1B호
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• pp.51-60
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• 2006

산업활동으로 인해서 발생하는 제강슬래그와 최근 선진국에서 환경개선 및 오염방지를 위한 용도로 활용하고자 활발히 연구되고 있는 제올라이트 등의 다공성 재료를 오염된 하천의 정체수역에 설치하여 저비용으로 수질을 개선시킬 수 있는 기법은 폐기물의 재이용 측면과 하천수질개선 측면에서 매우 필요하다. 현재 제철소에서 발생하는 부산물인 제강슬래그의 화학적성분은 주로 CaO, $SiO_2$, $Al_2O_3$, $Fe_2O_3$ 등으로 이루어져 있으며, 침전유발물질 및 흡착성물질이 함유되어 있다. 제강슬래그는 다공질 형태의 비표면적을 가지고 있어서 정화용 필터나 흡착재로 이용하기에 좋은 이점을 지니고 있다. 그리고 제올라이트는 양이온 교환특성, 흡착특성, 촉매특성, 탈수 및 재흡수특성 등의 이점을 지니고 있어서 축산농가의 환경개선, 도시의 생활하수의 처리, 공업폐수 처리, 음료수 수질개선, 방사성폐기물 처리 및 방사성 물질의 오염방지 등에 응용되고 있다. 그러므로 제강슬래그나 제올라이트를 Mattress/Filter의 채움재 및 수질정화용 여재로 활용함으로써 수질개선 등 효과를 동시에 얻을 수 있다. 본 연구에서는 제강슬래그와 제올라이트가 정체수역에 설치되는 Mattress/Filter시스템의 채움재로 활용할 때 공극률에 따른 수질개선효과를 파악하기 위하여 공극률을 38.6%인 P1, 45.8%인 P2 및 49.8%인 P3로 변화시켜 각각의 유입수와 유출수의 pH, DO, T-N, T-P 등을 측정하여 비교하였다. 수질개선에 사용된 Mattress/Filter시스템은 오염된 하천수가 Mattress/Filter시스템의 공극사이를 통과하면서 채움재에 형성된 다공질에 의한 여과작용과 생물막에 의한 접촉작용, 흡착작용 및 생물분해작용 등을 촉진시키는 기능을 가지고 있음을 알 수 있었다. 제강슬래그 및 제올라이트를 채움재로 사용한 Mattress/Filter 시스템은 쉽게 생물막을 형성시키고 유기물의 흡착을 촉진시켜 오염물질을 정화하는데 필요한 자정작용의 효과를 증대시키고 수질개선을 촉진시킬 수 있는 자연환경에서 하천정화에 이용될 수 있는 시스템임을 확인할 수 있었다.

• 한국환경보건학회지
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• 제35권5호
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• pp.365-375
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• 2009

Agriculture reservoirs need a systematic approach that can control water purity and water improvement. The area under study, Bunam Lake exceeds the agricultural water standard level due to contamination from the upper stream. When the Taean Enterprise City was planned, the water quality improvement plan was applied to minimize the environmental change. However, in order to continuously maintain the water quality in the Bunam Lake, it was essential to apply the Total Pollution Load Management System (TPLMs). In order to achieve the targeted water quality in the Bunam Lake, standard flow rates and targeted water quality levels were applied to obtain the loading capacity which is as follows : BOD 1,891.2 kg/d, T-N 1,945.7 kg/d, T-P 131.7 kg/d. Also, the regional development load was calculated as, BOD 1,083.6 kg/d, T-N 942.2 kg/d, T-P 61.8 kg/d, which is required to be deceased :- by BOD 378.4 kg/d, T-N 198.9 kg/d, T-P 31.6 kg/d in order to safely achieve the targeted water quality in the Bunam Lake.

• 설비공학논문집
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• 제14권2호
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• pp.127-133
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• 2002

The objectives of this paper are to develop an advanced GAX cycle named HGAX (Hybrid Generator Absorber heat exchanger) cycle, and to study the effect of key parameters on the cycle performance and the hot-water temperature from the condenser. New types of the HGAX cycle are developed by adding a compressor between the generator and the condenser- Type C (performance improvement and reduction of the generator temperature) and Type D (Hot-water temperature application). The solution temperature in the generator outlet is reduced to 168$^{\circ}C$ with the COP improvement of 19% compared to the standard GAX cycle. The hot-water temperature from the condenser is raised to 106$^{\circ}C$ for panel heating (Ondol heating) application.