• 융복합기술연구소 논문집
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• 제1권2호
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• pp.37-42
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• 2011

The purpose of this research is to improve nitrogen removal efficiency in winter season through rise of water temperature of extraneous water by using solar energy which is estimated to have great potential among new regeneration energy and while operating Plug-Flow Reactor to improve nitrogen removal efficiency by selecting A/O process among sewage waste water treatment processes as the necessity of solving the problem of nitrogen removal efficiency according to reduced water temperature in winter season and strengthening of water quality criteria regarding discharged sewage waste water suggested in the research background. Summarizing the research result, supply of solar energy source improves the function outstandingly when removing nitrogen, (nitrogen removal rate before operating solar energy 55.4% ${\rightarrow}$ nitrogen removal rate after operating solar energy 84.1%).

• 한국물환경학회지
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• 제26권5호
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• pp.816-821
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• 2010

It has been achieved 109.1 kg/d of BOD reduction that is equivalent to the amount of BOD loading discharged from 21,880 persons and dramatic decrease of the fallout ratio against water quality of effluent, from 42% to 9%, through technical support on ISTPs to be applied by the ISMSGA at the upper area of Geongan river in Yong-In city. It was clearly revealed that the most efficient configuration for ISTP was a series of anaerobic tank, equalization basin, aerobic tank, sedimentation tank, and then effluent tank. Also, the major causes on the fallout ratio of ISTP resulted in the lack of management (67.5%) and imperfect facilities (32.5%). Then, when compared the quantity of water supply with the design capacity of ISTP, the design capacity was estimated as 1.8 or 2.4 folds larger than the real quantity of water supply so that it is essential to punctually consider the key factors such as an estimation methods, the specificity of commission operator and construction by high systematic technologies to improve the water quality for the future.

• 상하수도학회지
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• 제34권1호
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• pp.23-33
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• 2020

With growing expectations for economic cooperation between the two Koreas, there is much interest in participating in the construction of infrastructure in North Korea. In particular, water and sewage infrastructure is the four major social infrastructures in addition to housing, transportation, electricity and telecommunications. North Korea is known to have severe water pollution and ecosystem destruction in major rivers, water pollution and soil pollution in mining areas are serious, and water and sewage infrastructures in cities other than Pyongyang are known to be weak. Preemptive investment in water supply and drainage in North Korea is the foundation for securing the quality of life of the North Korean and is the foundation of public health and industry. It is a leading investment to reduce the cost of unification and is a new growth engine for the water reloded industry. In this study, we proposed a plan to exchange and cooperate in water environment for building water infrastructure of North Korea by examining the data related to water quality, water resources, water disaster, related legal system and human resources exchange situations in North Korea.

• 한국농공학회지
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• 제43권2호
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• pp.94-104
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• 2001

A pilot study was performed at the experimental field of Konkuk University in Seoul, to examine the feasibility of the constructed wetland system for sewage and the effect of treated sewage irrigation on the paddy rice culture and its soil characteristics. The constructed wetland performed well, in that effluent concentrations of pollutants were significantly lower than concentrations of the influent. Median removal efficiencies of BOD$_{5}$ was about 78% and slightly lower during winter. Removal efficiencies form TN and TP were approximately 48 and 21%, respectively, and relatively less effective than that of BOD$_{5}$. Irrigation of treated sewage to paddy rice culture did not affect adversely in both growth and yield of rice. Instead, plots of treated sewage irrigation showed up to 50% more yield in average than the control plot. It implies that treated sewage irrigation might be beneficial to rice culture rather than detrimental as long as it is treated adequately and used properly. Soil was sampled and analyzed before transplanting and after harvesting. pH was slightly increased due to irrigation water, but it may not be concerned as long as the treated sewage is within the normal range. EC was increased in first year but decreased in second year, therefore salts accumulation in the soil could be less concerned. OM and CES was slightly increased, which might be beneficial on growing plants. TN did not show apparent pattern. Available phosphorus was decreased after rice culture, but the quantity of phosphorus(TP-available phosphorus) was rather increased which implies that excessive phosphorus supply may result in phosphorus accumulation in the soil. Overall, the constructed wetland was thought to be an effective sewage treatment alternative, and treated sewage could be reused as a supplemental source of irrigation water for paddy rice culture without causing adverse effect as long as it is treated adequately and used properly. For full-scale application, further investigation should be followed on environmental risk assessment, tolerable water quality, and fraction of supplemental irrigation.ion.

• 환경영향평가
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• 제11권1호
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• pp.25-36
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• 2002

The purpose of this study is to assess the environmental carrying capacity of Chongju City for the environmental management and the urban growth management. The urban environmental carrying capacity assessment of the city by the index of ecological footprint(EF), shows that the ecosystem of the city has been overloaded and most of the deficiencies has come from outside of the city. The EF index, the area of land per capita required for production and consumption in the city, was 1.731 ha per capita in 1989 and 1.901 ha per capita in 1999. On the other side, the ecologically productive land is 0.0175 ha per capita. It means that every citizen owes 1.88 ha per capita to the ecosystem in 1999. The land consumption of the city has increased by 0.1705 ha per capita during the last 10 years. The capacity of infrastructure and the service supply estimated by the Onishi model does not exceed the demand of the city in 1999. But the rapidly increasing population and fast urban growth need the expansion of the capacity. The water supply capacity of the city appears to be sufficient in 1999, but the water supply demand will increase in the future. The capacity of sewage treatment facilities seems to be sufficient, but the higher level of sewage treatment facilities should be adopted for the improvement of water quality as the generation of sewage will increase and its characteristics will also make the wastewater treatment difficult. Due to the decrease of solid waste generated, the land fill capacity for solid waste disposal is not insufficient at present, but the capacity will be saturated in the near future. Therefore, the scientific management system of solid wastes should be introduced. The air quality of the city meets both the national air quality standard and WHO recommendation standard, but the strong regulation and control of automobile emission gas such as CO, $CO_2$, NOx and HC is required for clean air.

• 한국지리정보학회지
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• 제3권3호
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• pp.90-97
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• 2000

본 연구는 중소도시에서 산재되어 있는 상수도 관망관리를 위하여 GIS의 적용시 개선되어져야 할 중요한 문제점을 파악하여 그 방안을 도출하기 위한 것으로 제천시의 관망도를 중심으로 분석 정리하였다. 이를 위하여 현재의 상수도 업무를 중심으로 관련분야와의 연계방안과 그 모형을 도출하였으며, 기 설치되어 운영하고 있는 상수도 시설물 관리시스템과의 비교를 통하여 문제점을 찾아 그 개선 방안을 제시하였다. 그 연구결과로 GIS에 의한 상수도관망관리시스템 구축에서는 관망시설정보, 누수방지시설정보, 조건에 따른 관망해석의 정보뿐만 아니라 수치지형정보, 도면전산화정보, 관련 수용가별 정보 등과의 연계를 통한 개발적용이 이루어질 때에 더욱 많은 효과를 기대할 수 있었다.

• 환경영향평가
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• 제22권6호
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• pp.581-589
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• 2013

Generally, Sewage Treatment Plants(STPs) are complexes systems in which a range of physical, chemical and biological processes occur. However, their performance strongly depends on the know-how acquired by the field-engineer. Recently, in order to solve this situations, various operation and management technologies based on the Instrumentation, Control and Automation(ICA) have been developed. As a economies-environmental affect point of view, this study was for the performance evaluation and assessment of results from the Smart Operation System(SOS) in full-scale STP. The SOS in STP consisted of the process monitoring module, including real-time influent prediction and effluent simulation, and the Smart Air Control(SAC) module. According to the results from field test for 2 years, the results of economical evaluation, amount of benefits and cost saving by the SOS have shown to be much higher than that of traditional operation. Nevertheless, the removal load(kg/yr) of BOD 13.3 %, COD 28.2 %, TN 44.4 % and TP 20.8 % were increased, respectively. Remarkable improvement of removal load could be achieved after the SOS was adapted. It was concerned that the SOS offer a user friendly functionalities and cost saving needed by the field-engineers. In addition, it was expected that the results of this study would supply helpful information for design and cost saving for the SOS in full-scale STP.

• 건축역사연구
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• 제28권6호
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• pp.55-65
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• 2019

Ganggyeong, a city which is located at riverside of Geum River, played a role to connect the inland cities and the coastal cities through the Geum river waterway. In Chosun dynasty, Ganggyeong was one of the three major markets in Korea, and at the same time, it was one of the two river docks in Korea. However, after the railway was installed in Korea, railroad was more important than waterway in transporting logistics and in 1911 Honam railroad and Ganggyeong railway station was installed. Thus it was necessary to reorganize urban structure of Ganggyeong city from the traditional river-dock city to modern railroad city. In addition, urban infrastructure to prevent flood damage was needed because Ganggyeong suffered from floods and water shortages every year. Therefore, between 1910s and 1930s large-scale social infrastructures including road, water and sewage system, river bank, floodgate was constructed not only to revitalize the declining city but also to prevent flood damage and water shortages that hinder urban development. The installation of urban infrastructure has enabled the urban expansion and development of Ganggyeong city, and it is still served as a basic urban structure.

• 한국지하수토양환경학회지:지하수토양환경
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• 제17권2호
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• pp.37-46
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• 2012

This study was conducted to identify groundwater recharge and discharge amounts of a representative urban-rural composite area located in Yongin city, Kyounggi-do, Korea. Groundwater recharge would be affected by mainly two processes in the study area: rainfall and leakage from public water pipelines including water-supply and sewage system. Groundwater recharge rate was estimated to be 13.5% by applying annual groundwater level data from two National Groundwater Monitoring Stations to the master regression curve method. Subsequently, the recharge amounts were determined to be $13,253{\times}10^3m^3/yr$. Leakage amounts from water-supply and sewage system were estimated to be $3,218{\times}10^3$ and $5,696{\times}10^3m^3/yr$, respectively. On the whole, a total of the recharge amounts was $22,167{\times}10^3m^3/yr$, of which 60% covers rainfall recharge and 40% pipeline leakage. Groundwater discharge occurred through three processes in the composite area: baseflow, well pumping, and discharge from urban infrastructure including groundwater infiltration into sewage pipeline and artificial extraction of groundwater to protect underground facilities from submergence. Discharge amounts by baseflow flowing to the Kiheung agricultural reservoir and well pumping were estimated to be $382{\times}10^3$ and $1,323{\times}10^3m^3/yr$, respectively. Occurrence of groundwater infiltration into sewage pipeline was rarely identified. Groundwater extraction amounts from the Bundang subway line as an underground facility were identified as $714{\times}10^3m^3/yr$. Overall, a total of the discharge amounts was determined to be $2,419{\times}10^3m^3/yr$, which was contributed by 29% of artificial discharge. Even though groundwater budget of the composite area was identified to be a surplus, it should be managed for a sound groundwater environment by changing deteriorated pipelines and controlling artificial discharge amounts.

• 한국습지학회지
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• 제18권3호
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• pp.267-274
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• 2016

농촌 지역 하수도 보급은 하천, 호소 및 습지와 같은 수계 수질 보호를 위해서 반드시 필요하다. 또한 안정적인 소규모 하수처리장 운영을 위해서는 유입 유량과 농도의 변화가 큰 소규모 하수도 특성을 고려해야 한다. 본 연구에서는 봉화군 18개의 소규모 하수처리장 운전 결과를 통해 유입유량비 (유입 유량 / 설계 유량) 특성, 소규모 하수처리장 처리 효율에 미치는 영향과 적정 유입유량비 산정에 관한 연구를 수행하였다. 분석 결과 유입유량비는 여름철에 가장 높은 것으로 나타난 반면, 유입 하수 농도는 가을철과 겨울철에 높은 것으로 나타났다. 유입유량비가 증가할수록 처리 효율이 증가하는 경향을 보였으며, 영양염류 처리 효율이 유기물과 부유물질 처리 효율에 비해 민감한 영향을 받는 것으로 나타났다. 안정적인 소규모 하수처리장 처리 효율을 위해서는 유입유량비 0.8 이상을 유지해야 할 것으로 판단된다.