• Journal of the Korean Geophysical Society
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• v.6 no.4
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• pp.245-259
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• 2003

Two multichannel analysis of surface wave (MASW) surveys were conducted over a soil site in Tacoma Water's Green River Facility, Washington, where construction of a chemical treatment facility had been planned. The purpose of the surveys was to compare soil stiffness characterized by shear-velocity (Vs) distribution before and after Deep Dynamic Compaction (DDC) operation that was designed to improve the soil stiffness. Site soil consisted of very heterogeneous gravel and cobbles in a sand-and-silt matrix. Results from each survey are represented by two 2-D Vs maps delineating Vs variation of soil below the surveyed lines. One map was constructed from those dispersion curves that were analyzed with a significant amount of subjective judgment involved, whereas the other map was constructed from those dispersion curves analyzed with as much objective information as possible. Comparison of 2-D Vs maps indicates that Vs actually decreased after the DDC operations, possibly due to the loss (or reduction) of cohesive bonding between soil particles caused by the compaction operations.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.9
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• pp.765-774
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• 2009

Fiber Dyeing and Finishing facility has been recognized as an important pollution source due to its consumption of large volumes of water and chemicals. Unit mass discharge for the conventional water quality parameters such as flowrate, SS, $BOD_5,\;COD_{Mn},\;COD_{Cr}$, TN, TP were estimated. To represent the respective industries, three companies were carefully selected based on its manufacturing goods, flowrate and location at various unit operations and processes. More than 90% of decrease in unit mass estimation between influent and effluent of BOD was observed. But the values themselves were similar to those of Fiber Manufacturing facility due to the high loadings of organic matter. Biodegradability of influent was almost three times higher than that of effluent. Unit mass discharge estimations of unit process (estimated in this study) based on space, products and raw material were similar to those of composite process (estimated by National Institute of Environmental Research), while big difference was observed in the other factors. Unit mass discharge factors calculated in this study can be used as the reference for the estimation of water pollution loading costs in Nakdong river basin. For the effective water pollution control and management, it is essential to characterize the various types of water quality parameters from the effluents of individual industrial wastewater treatment plants.

• Journal of the Korean Institute of Landscape Architecture
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• v.31 no.1
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• pp.11-22
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• 2003

This landscape design proposal was presented to a design competition for the Incheon-city Southern Region Integrated Disposal Treatment Facility. The site is located in Dongchun-dong, Yeonsu-gu, Incheon. The main design concepts are as follows: First, considering connection of the site with surrounding water, inner sea is designed as an environmentally friendly place and as a leisure-sports theme park in which several sports facilities and relaxing places are arranged. It is also designed for everyone: people of all ages, disabled, workers, visitors and local residents. The design was processed on the basis of survey, analysis of surrounding competing facilities and SWOT analysis. Second, the ecological planting model was developed by analyzing the natural vegetation map in the surrounding area and planted vegetation types in the seaside reclamation area. The model was then applied to the ecological community, park area and roadside trees, so as to harmonize with the local habitat. Third, the project is intended to launch private capital for managing the sports park and golf course. This will enable a entrepreneur to make flexible plans for golf training field that is expected to yield a good financial return. It is expected that this design would serve the local residents as a symbolic, environmentally friendly leisure-sports theme park.

• Proceedings of the Korea Water Resources Association Conference
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• 2019.05a
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• pp.412-412
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• 2019

Nature-based solutions (NBS) offer a wide variety of techniques that promote cost-efficient stormwater management practices. In particular, low impact development facilities utilize NBS principles to restore the ecosystem services in a highly-urbanized area. Despite the advancements in these technologies, several considerations should still be addressed to ensure optimum functionality and attainment of desired pollutant removal efficiency a LID facility. This study evaluated the mass flushing characteristics of pollutants in an urban catchment and the efficiency of a small constructed wetland (SCW) in treating urban stormwater runoff. 21 rainfall events from 2010 to 2018 were monitored to determine and quantify stormwater pollutants. The highest pollutant washoff was observed on rainfall depths ranging from 0.1mm to 10mm, whereas events with greater rainfall depths exhibited lower pollutant concentrations due to dilution effect. However, the SCW manifested lower pollutant-removal performance on rainfall depths exceeding 10mm due to the exceedance of the facility's design rainfall. This study is beneficial in assessing the dynamics of pollutant washoff and efficiency of LID facilities subjected under various external factors.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1688-1689
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• 2007

수 처리 분야에서 기존에는 각 시설 단위로 감시제어 시스템을 별도로 구축 해 왔다. 하지만 근래에는 이미 구축되어 있는 수 처리 시설이나 신설 시설들을 하나의 단위로 통합하려는 시도가 행해지고 있다. 이는 하나의 통합 시설이 여러 수처리 시설에 대한 감시 및 제어를 가능케 한다는 의미이다. 본 연구는 수 처리 시설의 감시 및 제어 통합 방안과 본 사의 통합시스템 개발에 관한 내용이다.

• Journal of Korean Society of Water and Wastewater
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• v.33 no.4
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• pp.281-289
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• 2019

Desalination plants are generally studied with higher operating costs compared to water supply facilities. This study was conducted to reduce the cost of water production and to preserve existing water resources. Therefore, the purpose of this study was to utilize the control valves to increase maximum efficiency, thereby reducing the power of the pumps and operating costs. Specific energy consumption was shown to reduce the process operating power by up to 1.7 times from 6.17 to $3.55kWh/m^3$ based on seawater reverse osmosis 60 bar. In addition, the water intake process was divided into pre, inter, and post-according to the use method of blasting, and the water treatment process was divided into pre, inter, and post blending. In order to reduce power consumption, the blending process was combined to operate the facility, which resulted in the reduction of power consumption in the order post > pre-inter> inter blending.

• Journal of Wetlands Research
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• v.23 no.4
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• pp.352-363
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• 2021

The purpose of this study was to evaluate the load of nutrients contained in the drainage discharged from the facility horticultural complex and to use them for re-use of fluids and design for introduction of water treatment plants. Representative hydroponic cultivation crops were selected as tomato, paprika, cucumber, and strawberry, and the total number of samples analyzed for water quality was 80. As a result of the analysis, since various fertilizer components such as N, P, K⁺, Na⁺, Mg²⁺, Ca²⁺, Si₄⁺, HCO₃^-, Cl^-, S^2-, Fe, Mn, Cu, Zn, Mo and B are contained at very high concentrations in the drainage, the need for water treatment was confirmed. Through statistical analysis, it was analyzed that the drainage concentration of strawberries was lower than that of tomatoes, paprika, and cucumbers. In the case of tomatoes, these essential ion concentrations are the highest, so it was confirmed that they are subject to valuable resources in terms of reuse of fertilizers. The load of N and P of the drainage discharged from the facility horticultural complex 1m² was analyzed. For N, the daily processing capacity of 4.0 kg of tomatoes, 3.3 kg of paprika, 3.0 kg of cucumbers, and 1.5 kg of strawberries was calculated based on 1 ha. It was suggested that the P concentration needs a scale and capacity that can handle 0.5 kg of tomatoes, 0.6 kg of paprika, 0.4 kg of cucumber, and 0.2 kg of strawberries per day. Through this study, the amount of nitrogen and phosphorus contained in the drainage discharged from the greenhouse of each crop was evaluated to analyze the economy. In addition, it was expected to be used as basic data that can be used to calculate the treatment capacity to be reflected when introducing water treatment facilities in facility horticultural complexes for sustainable agriculture.

• Journal of Korean Society of Environmental Engineers
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• v.33 no.3
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• pp.212-221
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• 2011

Wastewater treatment plants (WWTPs) are required to meet the reinforced discharge standards which are differentiated as 0.2, 0.3 and 0.5 mg-TP/L for the district I, II and III, respectively. Although most of WWTPs are operating advanced biological phosphorus removal system, the supplementary phosphorus treatment facility using chemical addition should be required almost at all WWTPs. Therefore, water quality data from several exemplary full-scale plants operating phosphorus treatment process were analyzed to evaluate the reliability of removal performance. Additionally, a series of jar tests were conducted to find optimal coagulants dose for phosphorus removal by chemical precipitation and to describe characteristics of the reaction and sludge production. Chemical costs and the increasing sludge volume in physicochemical phosphorus removal process were estimated based on the results of jar tests. The minimum coagulant (aluminium sulfate and poly aluminium chloride) doses to keep TP concentration below 0.5 and 0.2 mg/L were around 25 and 30 mg/L (as $Al_2O_3$), respectively, in the mixed liquor of activated sludge. In the tertiary treatment facility, relatively lower coagulant doses of 1/12~1/3 the minimum doses for activated sludge were required to achieve the same TP concentrations of 0.2~0.5 mg/L. Increase in suspended solids concentration due to chemical precipitates in mixed liquor was estimated at 10~11%, compared to the concentration without chemical addition. When coagulant was added into mixed liquor, chemical (aluminium sulfate) cost was estimated to be 4~10 times higher than in secondary effluent coagulation/separation process. Sludge production to be wasted was also 4~10 times higher than secondary effluent coagulation/separation process.

• Journal of Navigation and Port Research
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• v.41 no.3
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• pp.79-86
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• 2017

Ballast water filled into and discharged from the ballast tank of a ship has a negative impact on local marine environment due to various aquatic organisms contained therein. The IMO developed and adopted "The International Convention for the Control and Management of Ships Ballast Water and Sediments, 2004" with the purpose of protecting the marine environment from transfer of harmful aquatic organisms in ballast water carried by ships. The IMO BWM Convention was approved in September 2016 and ships must be equipped with ballast water management system after September 2017. Ships' ballast water treatment methods are divided into using active substances as electrolytic type, ozone type, chemical dosing type and using physical treatment type as filter type, ultraviolet type. It is also used with a combination of two methods. Electrolysis is superior in terms of cost and efficiency. In this study, basic principles, components, and land base test contents of electrolysis ballast water treatment system, a direct electrolyzed ballast water treatment system, were examined. Land base test was conducted with 300m3/h capacity device at the KIOST Geoje plant where the government test facility was installed. This test validated that the system meets IMO standards.

• Journal of Korea Water Resources Association
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• v.48 no.9
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• pp.711-717
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• 2015

This paper attempts to measure the economic benefits of advanced water treatment in five cities (Goyang, Paju, Gumi, Gimcheon, Chilgok), which are supplied water from Goyang and Gumi filtration plant. We used the dichotomous choice contingent valuation method to estimate WTP. Parametric interval-data model are used to obtaining the mean WTP estimates. The results show that the mean of additional WTP for advanced water treatment services were estimated to be KRW 231.3 and KRW 231.2 per $m^3$ using model with covariates and without covariates, respectively. Given the water supplies of Goyang and Gumi filtration plants ($59.675m^3/y$ and $93.734m^3/y$), the economic benefits of those advanced water treatments can be expected to be KRW 13.8 billion and KRE 21.68 billion. And the calculated B/C ratios are 3.7 and 2.1 when a lifespan of facility is 10 years. Advanced water treatment should be introduced in terms of the economic benefits and costs. Thus, this results can be useful in water policy decision-making.