• Membrane and Water Treatment
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• 제10권1호
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• pp.75-82
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• 2019

In a highly urbanized area, land availability is limited for the installation of space consuming stormwater systems for best management practices (BMPs), leading to the consideration of underground stormwater treatment devices connected to the stormwater pipe system. The configuration of a stormwater pipe network determines the hydrological and pollutant transport characteristics of the stormwater discharged through the pipe network, and thus should be an important design consideration for effective management of stormwater quantity and quality. This article presents a multi-objective optimization approach for designing a stormwater pipe network with on-line stormwater treatment devices to achieve an optimal trade-off between the total installation cost and the annual removal efficiency of total suspended solids (TSS). The Non-dominated Sorted Genetic Algorithm-II (NSGA-II) was adapted to solve the multi-objective optimization problem. The study site used to demonstrate the developed approach was a commercial area that has an existing pipe network with eight outfalls into an adjacent stream in Yongin City, South Korea. The stormwater management model (SWMM) was calibrated based on the data obtained from a subcatchment within the study area and was further used to simulate the flow rates and TSS discharge rates through a given pipe network for the entire study area. In the simulation, an underground stormwater treatment device was assumed to be installed at each outfall and sized proportional to the average flow rate at the outfall. The total installation cost for the pipes and underground devices was estimated based on empirical formulas using the flow rates and TSS discharge rates simulated by the SWMM. In the demonstration example, the installation cost could be reduced by up to 9% while the annual TSS removal efficiency could be increased by 4% compared to the original pipe network configuration. The annual TSS removal efficiency was relatively insensitive to the total installation cost in the Pareto-optimal solutions of the pipe network design. The results suggested that the installation cost of the pipes and stormwater treatment devices can be substantially reduced without significantly compromising the pollutant removal efficiency when the pipe network is optimally designed.

• 한국환경복원기술학회지
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• 제14권5호
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• pp.69-79
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• 2011

This study assessed the subsurface runoff and peak flow reduction in rain gardens. The results showed that the highest water retention was found in rain garden mesocosms in which Rhododendron lateritium and Zoysia japonica were planted, followed by mesocosms in which either R. lateritium or Z. japonica was planted, and the lowest water retention rate was found in non-vegetated control treatment mesocosms(${\alpha}$ < 0.05). Although higher rainfall intensity caused a decrease of peak flow reduction in both vegetated and non-vegetated treatments, peak flow reduction was the greatest in mesocosms with mixed plants. A rain garden can be an effective tool for environment-friendly stormwater management and improving ecological functions in urban areas. Depending on the purpose such as delaying runoff or increasing infiltration, various plant types should be considered for rain garden designing.

• Advances in environmental research
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• 제8권1호
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• pp.55-69
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• 2019

The generation of ferrous slag, an industrial by-product from the iron ore industry, results in serious environmental problems. The chemical compositions indicate 30-34% SiO₂, 30-34% CaO, 18-22% Al₂O₃ and 0.5-0.6% Fe₂O₃. The specific gravity, moisture content and pH are in the range of 1.3-1.65, 9.1-10% and 8.5-9.0 respectively. The major part of the slag is composed of sand-size particles. The problems of disposal of slag could be minimized by considering its use in various environmental engineering applications providing additional value to the by-product. This paper mainly focuses on the potential utilization and valorisation of ferrous slag in both water and wastewater treatments. It is effective for the treatment of water and wastewater containing nutrients, heavy metals and polluted river/stormwater.

• 한국환경과학회지
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• 제23권7호
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• pp.1299-1305
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• 2014

For evaluating the effect of various artificial planting soil properties on the Euonymus fortunei 'Emelad'n Gold' growth, a container green wall system experiment was conducted in a wall of greenhouse at Konkuk University, Glocal campus. The experimental artificial planting grounds were prepared with different organic soil conditioner ratios (Control, $A_4O_1$, $A_2O_1$ and $A_1O_1$) and with drought tolerance and an ornamental value Euonymus fortunei 'Emelad'n Gold' was planted. The soil and plant characteristics were investigated from April to Jun 2010. The volumetric soil moisture contents were significantly increasing order as the amount of organic soil conditioner level increased in order to $A_1O_1$ > $A_2O_1$ > $A_4O_1$ > Control. At 4 treatment, soil chemical properties were inversely related to organic soil container ratios increase. The differences of root collar caliper, number of branch, and survival rate between the organic soil conditioner ratio were not significantly affected by organic soil conditioner. But, plant height, internode length, leaf length and leaf width were significantly shorter on plants planted $A_1O_1$ than plants planted other treatments. Therefore, Euonymus fortunei 'Emelad'n Gold' had good growth response regardless of organic soil conditioner ratio and the plant is expected to be a highly valuable shrub for the green wall system if it should be considered in integration with stormwater retention or as a soil conditioner for increasing soil water contents in artificial planting soil.

• 한국환경과학회지
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• 제20권11호
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• pp.1417-1423
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• 2011

본 연구는 용기형 벽면녹화에서 유기질비료의 비율에 따른 노랑조팝나무의 생육을 실험적으로 평가함으로써, 빗물활용을 위한 적합한 식재지반 조성과 벽면녹화 수종으로서 관목류의 활용성을 높이고자 하며, 그 결과는 다음과 같다. 1. 6월 무강수 실험기간 동안 용기형 벽면녹화 식재지반 내 토양수분함량을 중량단위로 측정한 결과, $A_1L_1$ > $A_2L_1$ > $A_4L_1$ > $A_8L_1$ > $A_1L_0$ 순으로, 유기질비료의 비율이 높을수록 완만하게 감소하였다. 2. 유기질비료 배합비율에 따른 노랑조팝나무의 생육은 대조구인 $A_1L_0$과 비교해 볼 때, 실험구별 생육 차이는 확연하지 않았으나 $A_2L_1$이 전체 처리구 중 가장 양호한 생육상태를 보였다. 3. 생존율은 대조구인 $A_1L_0$에서 모든 식물이 고사한 반면, 유기질비료 비율이 높을수록 생존율은 향상되었다. 이러한 실험적 결과를 통해, 빗물활용 용기형 벽면녹화에서 유기질비료는 노랑조팝나무의 생육보다는 생존을 향상시키는 것으로 나타나, 빗물만으로 물공급이 이루어지는 벽면녹화에 건조기를 대비할 수 있는 녹화방안이라 본다. 또한 이와 더불어 식재지반 내 토양수분함량을 높이기 위한 토양개량제나 빗물저류시스템의 연계가 고려된다면 노랑조팝나무는 용기형 벽면녹화에 활용가능성이 높은 관목이라 판단된다.