• 보존과학회지
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• 제26권2호
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• pp.203-211
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• 2010

감은사지서삼층석탑의 표면오염물과 세척사례 조사 연구는 부재 표면에서 관찰되는 무기오염물의 성분분석과 오염물 제거 방법을 선정하기 위해 실시하였다. 표면오염물 조사는 육안관찰과 주사전자현미경, XRD를 이용하여 오염물의 상태를 파악하고 정성 정량분석을 통해 비교 분류하였다. 분석결과, 표면오염물은 철화합물이나 황화합물 등 화합물로 존재하며, 결정 형태는 원형, 타원형, 침상, 각형이 주를 이룬다. 오염물을 제거할 수 있는 방법을 검토한 결과, 미립재를 와류형식으로 분사하는 저압와류세척방법이 적당한 것으로 사료된다.

• 한국물환경학회지
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• 제34권4호
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• pp.382-390
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• 2018

In this study, the LIDMOD3 was developed to design and evaluate low impact development (LIDMOD). In the same fashion, the LIDMOD3 employs a curve number (NRCS-CN) method to estimate the surface runoff, infiltration and event mean concentration as applicable to pollutant loads which are based on a daily time step. In these terms, the LIDMOD3 can consider a hydrologic soil group for each land use type LID-BMP, and the applied removal efficiency of the surface runoff and pollutant loads by virtue of the stored capacity, which was calculated by analyzing the recorded water balance. As a result of Model development, the LIDMOD3 is based on an Excel spread sheet and consists of 8 sheets of information data, including: General information, Annual precipitation, Land use, Drainage area, LID-BMPs, Cals-cap, Parameters, and the Results. In addition, the LIDMOD3 can estimate the annual hydrology and annual pollutant loads including surface runoff and infiltration, the LID efficiency of the estimated surface runoff for a design rainfall event, and an analysis of the peak flow and time to peak using a unit hydrolograph for pre-development, post-development without LID, and as calculated with LID. As a result of the model application as applied to an apartment, the LIDMOD3 can estimate LID-BMPs considering a well spatical distributed hydroloic soil group as realized on land use and with the LID-BMPs. Essentially, the LIDMOD3 is a screen level and simple model which is easy to use because it is an Excel based model, as are most parameters in the database. This system can be expected to be widely used at the LID site to collect data within various programmable model parameters for the processing of a detail LID model simulation.

• 설비공학논문집
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• 제17권11호
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• pp.1060-1071
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• 2005

Passive gas dispersions over a 1/1000 scale terrain model at Eiffel type wind tunnel were reproduced by numerical simulation. Large eddy simulation was used to treat the sub-grid scale turbulences. The terrain features were represented by millions of point forces densely distributed over the solid surface using the virtual boundary method. The model simulations agreed very well with the experiments in a consistent fashion for all wind directions. The measured profiles of the wind speeds as well as the tracer gas concentrations were nicely simulated by the CFD model at most locations scattered over the model terrain. With scale factor adjusted and the thermal stratification effects incorporated, the CFD model was expected to provide reliable information on pollutant dispersions over the real complex terrains.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2003년도 추계학술대회 논문집
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• pp.340-345
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• 2003

This study, as a basic study for establishing a influence forecasting/estimating model when drain the deep sea water to the ocean after using it, carried out studies as follows; 1) estimating the amount of river discharge and pollutant loads inflowing into the developing region of deep sea water in East Sea, Korea 2) a field observation of tidal current, vertical distribution of water temperature and salinity, and 3-D numerical experiment of tidal current to analysis physical oceanographic status. The amount of river discharge flowing into the study area was estimated about $462.6{times}10^{3}m^{3}/day$ of daily mean in 2002 year. annual mean pollutant load of COD, TN and TP were estimated 7.02 ton-COD/day, 4.06 ton-TN/day and 0.39 ton/day, respectively. Field observation of tidal current results usually show about $20{\sim}40cm/sec$ of current velocity at the surface layer, it indicated a tendency that the current velocity decreases under 20cm/sec as the water depth increases. We could find a stratification within approximately the depth of 30m in field observation area, and the depth increases. We could find a stratification within approximately the depth of 30m in field observation area, and the differences of water temperature and salinity between the surface layer and bottom layer were about $18^{\circ}C$ and 0.8 psu, respectively. On the other hand, we found that there was a definite as the water mass of deep sea water about 34 psu of salinity.

• 한국농공학회지
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• 제44권5호
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• pp.116-126
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• 2002

Discharge pattern and water quality were investigated in the drainage water from about 10 ha of groundwater-irrigated paddy field in the growing season of 2001. Total discharge quantity was about 1,117.2 mm in which about 75% was caused by management drainage due to cultural practice of paddy rice farming and the rest by rainfall runoff where total rainfall was about 515 mm. Dry-day sampling data showed wide variations in constituent concentrations with average of 26.14 mg/L, 0.37 mg/L, 3.54 mg/L at the inlet, and 43.60 mg/L, 0.34 mg/L, 3.58 mg/L at the outlet for CO $D_{cr}$ , T-P, and T-N, respectively. Wet-day sampling data demonstrated that generally CO $D_{cr}$ followed the discharge pattern and T-P was in opposite to the discharge pattern, but T-N did not show apparent pattern to the discharge. Discharge and load are in strong relationship. And based on regression equation, pollutant loads from groundwater irrigation area are estimated to be 288.34, 1.17, and 5.45 kg/ha for CO $D_{cr}$ , T-P, and T-N, respectively, which was relatively lower than the literature value from surface water irrigation area which implies that groundwater irrigation area might use less irrigation water and result in less drainage water, Therefore, total pollutant load from paddies irrigation with groundwater could be significantly lower than that with surface water. This study shows that agricultural drainage water management needs a good care of drainage outlet as well as rainfall runoff. This study was based on limited monitoring data of one year, and further monitoring and successive analysis are recommended for more generalized conclusion.

• 환경영향평가
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• 제18권5호
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• pp.281-291
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• 2009

In Total Water Pollutant Load Management System of Korea, unit load approach based on land register data is currently used for the estimation of non-point pollutant load. However, a problem raised that land register data could not always reflect the actual land surface coverages which determine runoff characteristics of non-point pollution sources. As a way to overcome this, we tried to establish quantitative relationships between the aerial images (0.4m resolution) which reflect actual land surface coverages and the land registration maps according to the 19 major designated land-use categories in Kyeongan watershed. Analyses showed different relationships according to the land-use categories. Only a few land-use categories including forestry, road and river showed essentially identical and some categories such as orchard, parking lot and sport utility site showed no relationships at all between image data and land register data. Except for the two cases, all the other categories showed statistically significant linear relationships between image data and land register data. The analyses indicate that using high resolution aerial maps is a better way to estimate non-point pollutant load. If the aerial maps are not available, application of the linear relationships as conversion factors of land register data to image data could be an possible option to estimate non-point pollutant loads for the specific land-use categories in Kyeongan watershed.

• 한국습지학회지
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• 제11권1호
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• pp.91-97
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• 2009

본 연구는 강우강도에 따른 계분의 농지 환원시 비점유출로 인하여 수계에 미치는 영향을 연구하였다. 실험실 규모의 반응조를 제작하여 강우강도에 따른 표면유출수와 토양침투수에 대해 조사하였다. 표면유출수의 경우 10mm/hr 이하의 강우에서는 일어나지 않았으며, 20mm/hr에서 일부 유출되는 경향을 보였다. 32.4mm/hr시 가장 높은 표면유출을 보였으며 이때, $BOD_5$는 686mg/L, $COD_{Mn}$은 630mg/L의 농도를 나타내었다. 토양침투수의 경우도 32.4mm/hr의 강우시 많은 양의 계분퇴비가 유출되었고, 43.2mm/hr의 강우시에는 유출되는 양이 큰 폭으로 줄어들었다가 강우량이 증가할수록 유출되는 양이 다시 많아졌다. 비점유출량을 산정한 결과 $BOD_5$는 32.4mm/hr의 강우시 가장 높게 나타났고, T-N은 67.1mm/hr의 강우시 가장 높게 나타났다.

• 한국해양공학회지
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• 제19권1호
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• pp.14-19
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• 2005

As a basic study for establishing the input conditions of a forecasting/estimating model, used for deep-sea water drainage to the ocean, this study was carried out as follows: 1) estimating the amount of river discharge and pollutant loads into the developing region of deep sea water in the East Sea, Korea, 2) a field observation of tidal current, vertical water temperature, and salinity distribution, 3) 3-D numerical experiment of tidal current to analyze the physical oceanographic status. The amount of river discharge flowing into this study area was estimated at about $462.7{\times}103 m\^3/day$ of daily mean in 2002. Annual mean pollutant load of COD, TN, and TP were estimated at 7.02 ton-COD/day, 4.06 ton-TN/day, and 0.39 ton/day, respectively. Field observation of tidal current normally shows 20-40cm/sec of current velocity at the surface layer, and it decreases under 20cm/sec as the water depth increases. We also found a stratification condition at around 30m water depth in the observation area. The differences in water temperature and salinity, between the surface layer and the bottom layer, were about 18 C and 0.8 psu, respectively. On the other hand, we found a definite trend of 34 psu salinity water mass in the deep sea region.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제54권9호
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• pp.421-426
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• 2005

A wire-plate discharge system with a slit barrier has been proposed and investigated experimentally by focusing on the discharges on the slit barrier and ozone generation characteristics. This wire-plate discharge system with a slit barrier can generate an intensive corona discharges, and produce corona discharge twice, once from the corona wire electrode and second time from the surface and the slits of the slit dielectric barrier. As a result this propose wire-plate discharge system with the slit barrier can produce greatly increased ozone than without the slit barrier. This type of wire-plate discharge system with the slit barrier could be used for effective ozone generation as a means with retard to the removal of pollutant gas

• 수도
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• 제24권5호통권86호
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• pp.29-44
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• 1997

Sewage sludge produced in Korea was 1,275,800 tons (dewatered sludge cake) per year in 1996, which is 3,495 tons per day, 0.303% of 11,526,100 tons per day of sewage treated in 79 sewage treatment plants. Sludge production has been and will be increasing in accordance with construction of new facilities for sewage treatment. Most of the sludge is currently disposed by landfill and ocean dumping, but it is becoming difficult to find suitable sites for landfill, particularly in big cities such as Seoul. In addition, rapid increase of landfill cost is anticipated in a near future. Current trend for sludge disposal in advanced countries is land application. Over the past 10 to 20 years in the United States, sludge management practices have changed significantly, moving from disposal to beneficial use. They use biosolid for utilization instead of sludge for disposal. Under the Clean Water Act of 1972, amended in 1987 by Congress, the U.S. EPA was required to develop regulations for the use and disposal of sewage sludge. The EPA assessed the potential for pollutants in sewage sludge to affect public health and the environment through a number of different routes of exposure. The Agency also assessed the potential risk to human health through contamination of drinking water sources or surface water when sludge is disposed on land. The Final Rules were signed by the EPA Administrator and were published (Federal Register, 1993). These rules state that sewage sludge shall not be applied to land if the concentration of any pollutant in the sludge exceeds the ceiling concentration. In addition, the cumulative loading rate for each pollutant shall not exceed the cumulative pollutant loading rate nor should the concentration of each pollutant in the sludge exceed the monthly average concentration for the pollutant. The annual pollutant loading rate generally applies to applications of sewage sludge on agricultural lands. The most popular beneficial use of sewage sludge is land application. The sludge has to be stabilized for appling to land. One of the stabilization process for sewage sludge is lime stabilization process. The stabilization process is consisted of the stabilizing process and the drying process. Stabilization reactor can be a drum type reactor in which a crossed mixer is equipped. The additive agents are a very reactive mixture of calcium oxide and others. The stabilized sludge is dried in sun drier or rotary kiln.