• 한국대기환경학회지
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• 제21권3호
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• pp.367-375
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• 2005

Low-Z particle Electron Probe X-ray Microanalysis was applied to characterize MSW fly- and bottom -ash particle samples originated from two municipal incinerators (denoted as A and B) in Korea. According to their chemical composition, many distinctive particle types were identified. In A fly ash, the major chemical species are carbon-rich, aluminosilicates and many particles are composed of as a mixture of $ CaCO_3$ and other chemical species such as $CaSO_4$ or $CaCl_2$. For B fly ash, Fe, iron oxide, NaCl and NaCl-containing particles are the most abundant. In bottom ash, A and B were composed of similar chemical species such as carbon-rich, Fe, iron oxide, $CaCO_3$, and aluminosilicates. It was demonstrated that the single-particle characterization using this low-Z particle EPMA technique provided detailed information on various types of chemical species in the MSW ash samples. In addition, the technique has advantage over conventional analytical techniques in the point that both crystalline and glass-like ash particles can be analyzed at the same time.

• 한국세라믹학회지
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• 제33권7호
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• pp.771-778
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• 1996

Utilization of fly ash by-produced from coal fired power plants and classified as general waste became very important problem to solve in the environmental protection and recycling of waste materials. The possibility of large scale substitution of fly ash as a raw material for bricks and wet tiles was highly expected because the chemical compositions of fly ash were mostly Al2O3 and SiO2 and the properties of it were very similar with clay. Accordingly in order to investigate the substitutional limit these specimens were substituted from 0 to 100 wt% fly ash by 20wt% increment for clay. Fly ash-clay bodies were fired at 1200, 1250 and 130$0^{\circ}C$ and then their properties were measured, It was found that these specimens sintered at 125$0^{\circ}C$ had a good bending strength. Especially when these sintered bodies were added to 20, 40 and 60 wt% fly ash the bending strength of those were 201 , 205 and 191kg.cm2 respectively with the water absorption below 1%, This showed that fly ash could be substituted ab 60 wt% in this experiment.

• 한국지반공학회논문집
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• 제22권11호
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• pp.5-11
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• 2006

본 연구는 산업폐기물인 Bottom Ash의 재활용을 위한 목적으로 보통포틀랜드 시멘트와 Bottom Ash의 적정 혼합비를 산정 한 후 황토, 풍화토, Bentonite를 일정량 혼합하여 강도와 내구성에 대해 평가했고, 중금속 용출시험을 통해 환경적 영향을 검토했다. 그 결과 시멘트:Bottom Ash의 적정혼합비는 6:4이고, 황토, 풍화토, Bentonite는 6% 혼합하였을 경우 강도와 내구성에 가장 효과적 이였다. 또한 중금속 용출시험결과 지정 폐기물 기준에 훨씬 못 미치는 것으로 나타났다.

• 에너지공학
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• 제27권3호
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• pp.57-62
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• 2018

The development of coal-fired power plants to ensure energy security and electricity consumption is a matter for the Vietnam economy. However, the huge amount of ash discharged is a major environmental challenge. It is estimated that by the end of 2017, the amount of ash in the country is about 40 million tons and annually emitted over 16.4 million tons. While the quantity of coal-fired power plant is rising, the ash content will increase year by year if the ash doesn't treat well. The ash will be increased from 61 million tons in 2018 to 109 million tons in 2020, 248 million tons in 2025 and 422 million tons in 2030. The difficulties of coal-fired power plants are the problem of ash handling, some plants are at risk of closure because there are not enough dump capacity to storage. Therefore, Vietnam is in need of urgent measures to treat a large amount of waste from coal-fired power plants. The specific objectives of this study were as follows: (1) provide an overview of coal ash situation produced by coal-fired power plants in Vietnam; (2) study about regulations related to coal ash treatment; (3) comprehend the literature review of the cement sector status.

• 한국에너지공학회:학술대회논문집
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• 한국에너지공학회 1996년도 춘계학술발표회 초록집
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• pp.88-96
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• 1996

The characteristic analysis of fly ash generated from a fired power plant using bunker-C oil has been investigated. Ash size distribution by an optical microscopy with image processing technique, morphological shape by a scanning electron microscope(SEM) and microscope, chemical composition by the inductively coupled plasma emission spectrometry(ICP), and resistivity measurement as a function of temperature and moisture content by the resistivity meter are performed. A study of physical, chemical and electrical characteristics of bunker-C fly ash plays an important role of improving the performance of an electrostatic precipitator and protecting air pollution. The samples of bunker-C fly ash for analysis were collected from the electrostatic precipitator hopper of Ulsan Power Plant Unit 1 and Pusan Power Plant Unit 1. Mass median diameter(MMD) of bunker-C fly ash was measured 12.7${\mu}{\textrm}{m}$, while MMD of fly ash generated from the mixture of bunker-C oil(40%) and domestic anthracitic coal(60%) was 25.7${\mu}{\textrm}{m}$. The morphological structure of bunker-C fly ash consisted of fine particles of non-spherical shape. The primary chemical components of bunker-C fly ash were composed of SiO2(2.36%), Al2O3(4.91%), Fe2O3(14.33%) and C(11.84%). Resistivity of bunker-C fly ash was found to be increased with increasing temperature at the range of 100~15$0^{\circ}C$ and was measured 103~104 ohm-cm.

• Nuclear Engineering and Technology
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• 제48권5호
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• pp.1230-1236
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• 2016

This study aims to determine the effect of fly ash with a high replacing ratio of clay on the radiation shielding properties of bricks. Some interaction parameters (mass attenuation coefficients, half value layer, effective atomic number, effective electron density, and absorption efficiency) of clay fly ash bricks were measured with a NaI(Tl) detector at 661.6 keV, 1,173.2 keV, and 1,332.5 keV. For the investigation of their shielding behavior, fly ash bricks were molded using an admixture to clay. A narrow beam transmission geometry condition was used for the measurements. The measured values of these parameters were found in good agreement with the theoretical calculations. The elemental compositions of the clay fly ash bricks were analyzed by using an energy dispersive X-ray fluorescence spectrometer. At selected energies the values of the effective atomic numbers and effective electron densities showed a very modest variation with the composition of the fly ash. This seems to be due to the similarity of their elemental compositions. The obtained results were also compared with concrete, in order to study the effect of fly ash content on the radiation shielding properties of clay fly ash bricks. The clay fly ash bricks showed good shielding properties for moderate energy gamma rays. Therefore, these bricks are feasible and eco-friendly compared with traditional clay bricks used for construction.

• 한국건축시공학회지
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• 제3권3호
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• pp.135-142
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• 2003

This study is for the great quantity use of fly-ash. For the producing of high volume concrete from the use of fly-ash, the method of replacement between bonding agents and fine aggregate by fly-ash was used at the same time. It was used that the adiabatic temperature rise of concrete about the mass member which had been produced by the method that was mentioned before, and the hydration heat of the core test pieces in concrete was measured. Also the core test pieces which were replaced with fly-ash was studied by the compressive strength's comparison between standard care test pieces and core test pieces. In the case of mass test pieces, hydration heat and the time to reach the highest temperature were decreased by an increase in replaced fly-ash's amounts of concrete. In addition, among the test pieces having the same amounts of concrete, the test pieces having more replaced amounts of fly-ash's fine aggregate showed higher hydration heat and the increased time to reach the highest temperature. Compressive strength was also increased by hydration heat's decrease according to fly-ash replacement. Replacement of fly-ash was more effective in high temperature environment.

• 한국지반환경공학회 논문집
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• 제11권5호
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• pp.25-34
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• 2010

본 연구에서는 전국 화력발전소에서 부산되는 7,200만톤에 이르는 누적 매립회량을 대량 활용하기 위해 매립회의 특성 연구를 진행하였다. 일부 화력발전소에서는 비회와 저회가 분리되어 매립되고 있으나, 대부분의 화력발전소에서는 혼합 매립되고 있어 매립회의 공학적 특성이 규명되지 않아 이러한 공학적 특성을 규명하고자 영흥화력본부, 삼천포화력본부에서 부산되는 매립회와 비회를 사용하여 실험을 실시한 후 두 발전소의 매립회와 비회의 공학적 특성을 비교 분석하였다. 석탄회를 건설재료로 활용하기 위해 시료의 물리적 특성을 규명하고자 비중, 단위중량, 입도분석시험을 실시하였고, 역학적 특성을 규명하고자 삼축투수시험, 직접전단시험, 일축압축강도시험, 다짐시험을 실시하였다. 그리고 각 발전소에서 부산되는 석탄회의 특성을 알아보고자 무연탄 및 유연탄을 사용하는 발전소에서 부산된 석탄회의 공학적 특성들을 비교 고찰하였다. 시험결과 경량성의 건설재료로써 유연탄 발전소에서 부산된 석탄회를 사용하는 것이 유리하며 뒷채움재로의 활용은 투수계수가 상대적으로 큰 무연탄을 사용하는 발전소에서 부산되는 석탄회를 사용하는 것이 효과적이라 판단된다. 본 논문에서는 영흥화력본부의 비회가 가장 작은 투수계수를 나타냈으므로 불투수층을 요구하는 현장에 적용하기에 가장 적합할 것이라 판단된다.

• 한국지반공학회논문집
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• 제23권11호
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• pp.77-85
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• 2007

본 연구에서는 준설토 및 Bottom ash를 동시에 재활용하기 위하여 개발된 복합지반재료의 역학적 특성을 고찰하였다. 본 실험에서 제작된 복합지반재료는 부산 신항 건설현장에서 채취한 준설토, 시멘트, 기포 및 삼천포 화력발전소에 서 발생한 Bottom ash로 구성되어졌다. 다양한 배합비로 제작된 복합지반재료의 역학적 특성을 고찰하고, 특히 Bottom ash 혼합에 의한 역학적 거동 특성을 조사하기 위하여 다양한 실내실험이 수행되어졌다. 복합지반재료에 대한 실험결과 응력-변형 관계와 일축압축강도는 배합조건에 크게 의존하는 것으로 나타났고, 특히 Bottom ash 혼합시 압축강도 및 응력-변형 곡선의 기울기가 증가하는 Bottom ash 보강효과를 확인하였다. 복합지반재료의 압축강도는 양생기간이 증가할수록 증가하며, 28일 강도는 7일 강도의 약 $1.7{\sim}1.8$배 증가하는 것으로 나타났다. 복합지반재료의 단위중량은 기포함량에 크게 의존하였다. 복합지반재료의 변형계수($E_{50}$)은 Bottom ash의 혼합으로 인해 강도가 증가함에 따라 증가되었다.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1995년도 추계학술발표회논문집(2)
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• pp.812-817
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• 1995

세슘의 고정화재료로서 Si/Al의 몰비가 약 2인 석탄화력발전소 산업폐기물인 fly ash와 CsNO$_3$의 반응이 열중량 분석기, 시차 열분석기 및 X-ray 회절분석기를 이용하여 공기분위기에서 수행되었다. X-ray 회절 분석결과 fly ash는 mullite와 quartz로 되어 있었고, fly ash와 세슘과의 반응물인 pollucite(CsAlSi$_2$O$_{6}$)의 생성이 확인되었다. 따라서 기상의 세슘화합물을 효과적으로 제거하기 위한 포집제의 원료물질로서 fly ash의 이용 가능성을 확인하였다.