• KSCE Journal of Civil and Environmental Engineering Research
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• v.37 no.2
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• pp.497-505
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• 2017

TDF (Tire derived fuel) Fly ash is an industrial by-product when scraped tire was used a fuel source at the power plant. TDF Fly ash has been classified as domestic waste at the workplace so far and has not been appropriately utilized. We conducted a fundamental physical property test of asphalt mixture to investigate the possibility of using TDF Fly ash as a mineral filler of asphalt mixture for exploring new usage strategies. TDF Fly ash meets KS F 3501 asphalt mixture mineral filler criteria. And the optimal asphalt binder amount was determined to be 4.5% by Marshall design. Mineral filler content was determined at 3% and analyzed by comparing using mineral filler as stone powder. The basic physical property test of the asphalt mixture was evaluated to the provision indicated in "Production and Construction Guidelines for Asphalt Mixture" published by the Ministry of Land, Infrastructure and Transport. In the test, Marshall stability test, dynamic immersion test, tensile strength ratio test, wheel tracking test were carried out. As a result of the experiment, Marshall stability and dynamic stability satisfied the standards, and confirmed the stability and Dynamic immersion and tensile strength ratio test that TDF Fly ash is more effective for scaling and moisture resistance than stone dust. Therefore, in this research, it is expected that multilateral utilization of TDF Fly ash, and a positive effect can be also expected.

• Journal of the Korea institute for structural maintenance and inspection
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• v.9 no.4
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• pp.261-269
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• 2005

The object of this research is to produce alkali activated fly ash-cement using low calcium fly ash as substitute for portland cement. The experimental program included activation of fly ash by a strong base(NaOH) at different concentration, temperature, and liquid-to-fly ash ratios. To achieve for higher compressive strength of the hardened product, sodium meta silicate is added to the alkaline solution. From the factors considered on strength development, the ratio of liquid/fly ash, the activator concentration and temperature always result to be significative factors. The optimization studied show that the alkaline solution concentration of $NaOH(210g)+Na_2SiO_3{\cdot}9H_2O(30g)+H_2O=1L$ at $50^{\circ}C$ produces the best alkali activation effect for the low calcium fly ash. SEM and XRD patterns showed that the components of alkali-activated fly ash consist mainly of mullite, quartz and amorphous aluminosilicate.

• Journal of the Korean Society of Tobacco Science
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• v.19 no.2
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• pp.92-101
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• 1997

This study was conducted to investigate the effect of fly ash on the yield and quality and to determine the optimum application amount of fly ash for tobacco(Nicotiana tabacum L). Two kinds of fly ash, anthracite and bituminous coal, were treated with different levels of 0, 20, 40, 60 MT/ha. Dry weights of tobacco at middle and topping growth stage were increased with application of fly ash, showing the highest dry weight at 40 MT/ha in both kinds of fly ash. It was showed that the bituminous coal had a little more effective for yield than that of anthracite. Comparing with the control, yields of tobacco applied with fly ash were significantly increased about 17.7% and 17.1% by the application of bituminous coal and anthracite, respectively. Quality of flue-cured leaves was better by application of fly ash than that of the control. The quality index was given the highest at 40 MT/ha for bituminous coal increasing by 24.6% and at 60 MT/ha fur anthracite increasing by 13.4% compared with the control. The economical efficiency considered of the yield and quality of tobacco was the highest at 40 MT/ha of bituminous. Soil pH, contents of available P2O5, organic matter, exchangeable Ca2+ and Mg2+ of soil during the growing season were increased by application of fly ash, showing more effectiveness in bituminous than that in anthracite. By the application of fly ash, the nutrients availability and the acidity of soil were reformed and they caused significantly the increase of growths yield, and quality of tobacco. By the application of lime reforming soil acidity, growth response, yields and quality of tobacco were not increased compared to the control, although the effect of reforming soil pH was remarkable.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.5 no.4
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• pp.414-422
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• 1995

Coal fly ash was calcined and elutriated for recycling as ceramic raw materials. C Crystal phases, morphologies, chemical components, particle size distributions and Ig. loss of as-received, calcined and elutriated coal fly ash were investigated to study the effects of the calci nation and elutriation on the coal fly ash classification. The experimental equations, which were used in elutriation of clay, were examined in order to find out which equation is appropriated for coal fly ash classification. It turned out that Rittinger's equation is relatively well matched for the fly ash. Having nothing to do with the treatment conditions, the crystal phases of coal f fly ash were mullite, quartz. Calcite peak was detected in as - received and elutriated coal fly a ash; however, it disappeared in calcined coal fly ash. As - received coal fly ash consists of various type of particles such as a cenosphere, coke type, silicate type, whisker type and aggregat e ed type. In case of calcined coal fly ash, coke type particles were eliminated and agglomerated type particles were relatively increased. Most of the particles that were relatively spherical cenosphere in the 4th step of elutriator. Particle size distribution was narrowed by calcination a and elutriation. Especially, in elutriation, particle size distribution was very narrow.

• 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.

• Nuclear Engineering and Technology
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• v.44 no.3
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• pp.331-342
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• 2012

Since the opening of the Shin-Kori #1,2 in 2005, fly ash mixed concrete has been used for NPP concrete structures under construction in Korea with the aim of preventing aging and improving durability. In this paper, the quality suitability of fly ash manufactured in Korea is assessed and the basic physical properties of fly ash mixed concrete and its durability against primary causes of aging are verified through experimental methods. Because of the internal structure filling effect from the pozzolanic reaction of fly ash and the resulting improvements in mechanical performance in such areas as strength and salt damage resistance, the durability of fly ash mixed concrete is shown to be superior. It is judged that this result can be applied in measures not only for improving the safety of NPP structures in operation in Korea but also for implementing effective structure life management should extending the life of structures be needed in the future.

• Proceedings of the Korea Concrete Institute Conference
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• 1999.10a
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• pp.99-102
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• 1999

In the study, the effect of the replacement content(20, 40, 60, 80%) and particle fineness and the chemical activator of the fly-ash on the flow and strength development of mortar was investigated. We found that the higher raito of the fly-ash replacement produced the lower the mortar strength and the higher fineness of the fly-ash yielded the higher strength. Also, we used Na2SO4 as activator of fly-ash to rise compressive strength mortar. The result as follows: the fly-ash mortar which stimulated by chemical activator, was higher strength development at early than the fly-ash mortar without chemical activator. But in the late age, the result indicated adversely.

• Proceedings of the Korea Concrete Institute Conference
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• 1998.10c
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• pp.105-110
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• 1998

The purpose of this was to examine the used of fly ash as a type of construction material. In this paper the results from a recent study on development of a cement composite utilizing relatively large amount of fly ash are presented. The flowable fly ash-cement sand composite was investigated for strength and flowability characteristics. The independent variable considered were: fly-ash content, sand content, and ratio of water to cementitious materials. Results of this study show that high volume fly-ash composite can be proportioned to obtain 10~15kg/$\textrm{cm}^2$ compressive strength at 28 days. For applications requiring strength between 10kg/$\textrm{cm}^2$ and 15kg/$\textrm{cm}^2$, the mixture with fly ash-cement ratio of 5.6 and sand-cement ratio of 28 with relatively high water content may be used. Slump was held at 25$\pm$1cm for all mixtures produced compressive strength at 28 days were found to range from 5kg/$\textrm{cm}^2$ to 13.7kg/$\textrm{cm}^2$.

• Journal of the Korea Concrete Institute
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• v.11 no.5
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• pp.41-49
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• 1999

This study dealt with the applicability and quality control of the concrete using fly ash produced in combined heat power in a construction site. Firstly, chemical and physical characteristics of the fly ash produced in combined heat power plant re analysed. Also, after investigating the properties of flesh and hardened concrete through various experiments, the fly ash concrete was placed in depositing construction in Ulsan Petrochemical Service Co. This field application was focussed on the quality control system in the site as production, placing and curing of concrete. As the result of this study, the quantity of CaO in the fly ash is relatively high based on the chemical analysis. The fly ash concrete showed slumping maintenance and high viscosity properties in the optimal mixing conditions (W/B:44~45%, S/a:$45\pm$2%, W:185kg/m). And, quality control and assurance of the fly ash concrete in actual site were verified by various testing methods.

• Proceedings of the Korea Concrete Institute Conference
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• 1999.04a
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• pp.89-94
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• 1999

The workability of high strength concrete using high range water reducing admixture is varied rapidly according to elapsed time. For using the high strength concrete in situ, careful caution on workability is necessary. By using fly ash as a admixture, the slump loss of concrete can be reduced considerably, but the early strength of concrete used fly ash is smaller than that not used fly ash. For the purpose of elevating the utilization of fly ash on high strength concrete, the high fluidity retention and the strength development in early age are necessary in concrete used fly ash. In this study, to improve the fluidity retention and to acquire strength development on concrete used fly ash, the gypsum is applied.