• Journal of Korean Society of Environmental Engineers
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• v.38 no.10
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• pp.574-579
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• 2016

This study assessed feasibility of making granular fertilizer with fly ash from a sewage sludge incinerator in Korea. Composition, characteristics, strength, and heavy metal contents of the granular fertilizers were investigated. Due to its high contents of phosphorus, fly ash from a sewage sludge incinerator could be used to make fertilizers. Granulation rates (2-4 mm granules) over 80% could be achieved as the fly ash contents were 15% or less of the fertilizer. Leaching tests of the fertilizers, based upon the Korean Standard Methods for Solid Wastes, showed the concentrations of heavy metals less than the risk limits. However, contents analysis of the fertilizers, based upon the Korean Standard Methods for Soils, experienced higher levels of heavy metals than the risk limits as the fly ash content exceeded 7% of the fertilizer. Thus, the fly ash needs to be added less than 7% of the fertilizer if there is no pretreatment to remove heavy metals.

• Journal of the Korean Society of Industry Convergence
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• v.3 no.1
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• pp.37-42
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• 2000

액체 분무가 벽면의 평평한 면에 충돌할 때의 거동에 대해 실험을 통하여 조사하였다. 각 분사노즐과 벽면까지의 거리 그리고 분사 속도에 있어서 충돌점에서의 액체 액막의 비산 거동과 평면에서의 액막의 흐름에 대하여 관찰하였다. 충돌점에서 비산하는 액적의 비산율을 정량적으로 측정하였다. 분사속도가 증가에 의해 충돌 거동은 5개의 영역으로 분류되며, 분사속도가 증가하면 비산율도 증가하게 된다. 또한, 충돌거리가 분무의 분열점보다 길때의 분사량의 약 반 정도가 비산하게 되는 결과가 얻어졌다.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.05b
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• pp.312-313
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• 2003

환경부 훈령 제500호 "비산먼지 저감대책 추진에 관한 업무처리 규정(2001.9.4)"에 따르면 "비산먼지"라 함은 일정한 배출구 없이 대기 중에 직접 배출되는 먼지를 말하며, 대기환경보전법에서는 비산먼지 발생사업의 신고 및 발생억제 의무를 규정하고 있다. 미국 국가배출목록(U.S. EPA, 2000)에 의하면 미세먼지(PM10) 배출량의 89%를 비산먼지가 차지하고 있으며 이러한 수치는 비산먼지가 대기질에 미치는 영향도가 어느 정도인지를 예시하고 있다. 한편 우리나라의 경우 현재 미세먼지 배출목록에서 비산먼지 항목이 누락되어 있기 때문에 효율적인 대기질 관리를 위해서는 전국 지역별 비산 먼지 배출 목록의 구축이 시급한 것으로 사료된다. (중략)

• Clean Technology
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• v.19 no.4
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• pp.453-458
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• 2013

Fly ash has capacity to oxidize or adsorb mercury in a flue gas. Mercury oxidation and adsorption efficiencies of fly ash vary depending on the properties of fly ash. This study was designed to understand reaction characteristics of mercury with fly ash components. The fly ash components were tested to determine their oxidation and adsorption capabilities for elemental mercury and oxidized mercury. A sample was synthesized with fly ash components and tested. The test results were compared with those of the fly ash sample obtained from a coal-fired power plant. $Fe_2O_3$, CuO and carbon black showed higher oxidation or adsorption efficiency for elemental mercury while CaO, MgO, CuO and carbon black showed higher adsorption efficiency for mercury chloride. In addition, the synthesized sample showed comparable mercury oxidation and adsorption efficiencies to the fly ash sample.

• The Journal of the Korea institute of electronic communication sciences
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• v.17 no.6
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• pp.1237-1242
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• 2022

Fugitive dust, which accounts more than 50% of fine dust, is an air pollutant, that is generated by a lot in construction work(29.5%) and the law provides standards for facility installation and measures to control this. However, small-scale construction sites are not subject to management standards, and the law to measure and manage fugitive dust generated from construction sites is insufficient. In this paper, we designed and implemented the method to easily measure and monitor fugitive dust using the digital optical method for turbidity of dust. We presented the method to measure the turbidity of fugitive dust using the digital optical method and measured the actual turbidity of fugitive dust at the construction sites after implementing the fugitive dust measurement system.

• Korean Journal of Construction Engineering and Management
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• v.18 no.5
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• pp.68-76
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• 2017

A recent issue of fine dust is particulate matter with a diameter of less than $10{\mu}g/m^3$. It's classified as a pollutant that has a fatal effect on the human body when inhaled. The fugitive dust must be well controlled, since the adverse effects of dust on the surroundings are increased when the dust is blown away by the wind. Since the construction site is the place where the most fugitive dust is discharged in Korea, managing the fugitive dust discharged from the construction site can be an important issue to solve the problem of domestic fine dust. However, since the construction industry in Korea is the largest in Korea, it is difficult to control the emission of fugitive dust in the domestic construction site. In this paper, we compare and analyze the fugitive dust regulations applied to construction sites in major cities and propose the improvement plans to help control the fugitive dust generated in domestic construction sites.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.41 no.6
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• pp.745-750
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• 2021

As public concern for fine dust has increased, so too has the interest in fugitive dust. Fugitive dust generated at construction sites, which is then scattered by vehicles moving around the sites, accounts for a significant portion. Small construction sites, which comprise the majority of construction sites, are often not adequately managed, because there are no regulations on fugitive dust for such sites. Therefore, in this study, in order to contribute to the establishment of fugitive dust management regulations on small-scale construction sites and to prepare measures to reduce fugitive dust, we measured and analyzed fugitive dust generated at small-scale building sites in Seoul. The fluctuations of fugitive dust generated at small-scale sites over time were checked, and the relatively low concentration when measured behind fences and railings suggested that fence installation is an appropriate method of reducing fugitive dust.

• Journal of the Korean Society of Industry Convergence
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• v.7 no.1
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• pp.5-11
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• 2004

벽면에 충돌하는 액체 분무의 충돌 거동과 액적 비산에 관하여 실험을 통하여 조사하였다. 액체 분무는 홀노즐에 의해 직경 40mm의 충돌판에 분사하게 된다. 액체 분무는 반경방향으로 퍼져나가 5개의 영역으로 분류되어 나타내게 된다. 난류 혹은 층류 분무의 경우, 충돌판에 충돌한 후 두꺼운 액막을 형성하게 되며, 이러한 상태에서 충돌하는 분무의 비산량은 매우 적으며 충돌 거리에 영향을 받지 않는다. 한편, 파동이 있는 분무의 충돌은 수력도약(Hydraulic jump)과 함께 반경방향으로 엷은 액막을 형성하게 되며 비산율도 증가하게 된다. 액체분무의 초속도가 증가하면 비산율도 증가하게 된다. 분열이 일어난 후에 충돌하는 파동 분무의 비산율은 분열이 일어나기 전에 비해 약 2~3배 정도 크게 나타난다. 비산율은 웨버수(Weber number)를 이용하여 요약할 수가 있다.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.40 no.1
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• pp.105-110
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• 2020

This study provides a method and data for predicting the flight initiation wind speed of wind-borne debris. From the force equilibrium acting on debris including aerodynamic and inertia forces, the equation for predicting the flight initiation wind speeds are presented. Wind tunnel tests were carried out to provide necessary aerodynamic data in the equation for the debris with various aspect ratios. The proposed equation for flight initiation wind speeds was validated from free flying tests in the wind tunnel. The flights of debris were mostly initiated by slip when width to thickness was less than 10, otherwise overturning were dominant. The actual flight initiation speeds were lower than that of the computed ones. The surface boundary layer flow and the gap between the debris and surface might affect the prediction error.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.8
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• pp.547-553
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• 2013

This paper investigates the effect of coal-fired fly ash on dry $CO_2$ sorbents as the supports and additives. For this purpose, various kinds of dry sorbent were manufactured by mixing fly-ash, the primary $CO_2$ absorption components (NaOH and CaO) and water with their different combination. Thereafter, their $CO_2$ absorption performance and the property were analyzed. As a result, variation of absorption efficiency and temperature as well as $CO_2$ desorption of the sorbents are confirmed, which may be primarily ascribed to fly-ash addition to the sorbents. Particularly, fly-ash effect is strongly measured in the sorbent manufactured by mixing all four components (named WNCF sorbents). Absorption efficiency of WNCF sorbents at $550^{\circ}C$ is 35.6% higher than that of flyash free sorbent and desorption is solely observed in WNCF sorbents. Fly-ash in WNCF sorbents leads to increase the dispersity of $CO_2$ absorption components and decrease their particle size in the sorbents. In addition, fly-ash is used as the supports and pozzolanic reaction is hindered by NaOH in WNCF sorbent. Furthermore, $CO_2$ desorption from the sorbents may be due to fly-ash. The interaction between fly-ash and $CO_2$ absorption components substantially attenuate the strength between captured $CO_2$ in CaO and NaOH.