• KSCE Journal of Civil and Environmental Engineering Research
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• v.11 no.1
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• pp.145-151
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• 1991

The final purpose of this study is to examine the uses of coal ash, by-product from thermal power plant as a type of filling-embankment materials and the reuses of ash ponds. In this time, to investigate the dynamic properties, we made the test piece specimen with coal ashes, and obtained the damping ratio. In place(ash pond), the damping property by underground wall was investigated before and after soil improvements. The damping ratio of coal ash test piece specimen of 12% cement is the highest and that of 9% cement or chemical grout, that of 6% cement is in order. In same coal ash test piece, the damping ratio increases with decreasing the void ratio. In conclusion, it could be said that the damping ratio increases with the stiffness of materials. In the ash pond, the damping effect is the most when trench is set through the vibration wave propagation course, and when soil is improved the higher stiffness of the improved soil is, the more damping effect appeared. It is justified to obtain not only the dropping of permeability and the strength increase, but also the damping effect fairly by soil improvements.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.11
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• pp.941-946
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• 2009

Two types of synthetic zeolites, commercially used (Z-WK) and synthesized by coal fly ash (Z-C1), and raw coal fly ash(F-C1) were examined for its kinetics and adsorption capacities of cobalt. Experimental data are fitted with kinetic models, Lagergen $1^{st}$ and $2^{nd}$ order models, and four types of adsorption isotherm models, Langmuir, Freundlich, Redlich-Peterson, and Koble-Corrigan. Synthesized zeolite (Z-C1) which had 1.51 of Si/Al ratio was synthesized by raw coal fly ash from a thermal power plant. Adsorption capacities with three types of adsorbents, Z-WK, Z-C1, and F-C1, were in the order of Z-C1 (94.15 mg/g) > F-C1 (92.94 mg/g) > Z-WK (88.56mg/g). The adsorption kinetics of Z-WK and Z-C1 with cobalt could be accurately described by a pseudo-second-order rate equation. The adsorption isotherms of Z-WK and Z-C1 with cobalt were well fitted by the Langmuir and Redlich-Peterson equation. Z-C1 will be used to remove cobalt in water as a more efficient absorbent.

• Journal of the Korean Institute of Gas
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• v.8 no.4 s.25
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• pp.55-61
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• 2004

This paper provided a counter measures against the troubles and accidents that are likely to take place in the power plant using hydrogen gas as a coolant for the cooling system of the generator. Because of the extremely wide flammability limits of hydrogen in comparison to the other flammable gases, the safety measures against the hydrogen accidents is very important to ensure the normal operation of electric-power facility. This study's purpose was a presentation of standard model of safety management of hydrogen equipments in the coal firing power plant such as following items: 1) providing the technical prevention manual of the hydrogen explosions and hydrogen fires occurring in the cooling system of power generator; 2) the selection of explosion-proof equipments in terms of the risk level of operating environment; 3) the establishment of regulations and counter measures, such as the incorporation of gas leakage alarm device, for preventing the accidents from arising, 4) the establishment of safety management system to ensure the normal operation of the power plant.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 1999.10a
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• pp.262-263
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• 1999

현재 저온 플라스마를 이용한 대기오염물질 제어 연구가 국내외적으로 활발하게 진행되고 있나. 특히 국내에서는 강화된 대기오염에 대한 배출허용기준을 준수하기 위하여 황산화물 및 질소산화물을 제거하기 위한 연구가 활발히 이루어지고 있으며, 이와 병행하여 휘발성 유기화합물(VOCs; Volatile Organic Compounds)에 대한 연구도 진행중에 있다.(중략)

• Proceedings of the Korea Concrete Institute Conference
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• 1999.04a
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• pp.613-618
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• 1999

This paper discuss the chemical, physical and mineral properties of classified fly ashes by electrostatic precipitator and calcinated fly ashes at 50$0^{\circ}C$. The electrostatic precipitator in coal fired power plant has a number of hopper in the direction of flue gases. The properties of fly ashes collected at each hopper in the electrostatic precipitator are different. Superfine, fine and ordinary fly ashes can be collected respectively at each hopper. The carbon content in fly ash is influenced on the viscosity of paste. By calcination, the carbon content in fly ash is decreased and the fluidity of paste is improved.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.04a
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• pp.153-158
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• 2000

This study was carried out in order to investigate the relationship roundness of fly ashes and fluidity of fly ash cement paste. electrostatic precipitator system in coal-fired power plant have many successive collection fields in the direction of flue gas travel. In experiment, the roundness of fly ashes collected from the same location had similar values regardless of the load or boiler, and they increased going from the 1st collection filed to third collection filed in the direction of gas movement. In considering the relation between roundness of fly ashes and fluidity of fly ash cement paste, it has a high correlation.

• Journal of the Korean Professional Engineers Association
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• v.46 no.2
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• pp.44-50
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• 2013

The treatment of city life wastes is headache problem. Now, only small portion of burnable wastes is burnt at modern process incinerators, the other large portion is buried in the soil by landfill method. The burnable wastes will be increased year by year. The dioxin, the cancer-causing agent, produced by incineration of wastes influences harmful effect to national human health. The new idea of burnable wastes treatment is using the city life wastes as auxiliary fuel of fluidizing bed combustion boiler of large scale coal-fired power plant. The dioxin-free treatment of burnable wastes is sucessfully achieved by burning the wastes, in flyash storm at fluidizing bed combustion boiler.

• Journal of Energy Engineering
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• v.12 no.3
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• pp.165-176
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• 2003

In this study, the exergy analysis is conducted on the well known performance of already developed system and then compared with the efficiency of each equipment to propose optimum operation of the system. The system used in this study is 500 MW coal firing power plant. The efficiency of the boiler is 67% and the condenser is 99% by exergy analysis. The exergy consumption of the boiler was 32.95% at 100% load. The exergy consumption of the high pressure turbine and the low pressure turbine is 8.31% and 8.12%, respectively. Together with the concrete study on the object of performance revision of the low efficient development system proved in this study, if detailed exergy analysis on the operation condition of the equipments of the development system presently being operated is continued, then it is expected to help minimize the exergy consumption of relatively low efficient parts that are worn-out or miss-installed.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.42 no.4
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• pp.78-83
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• 2010

In this study, the possibility of the use of a new raw material in paperboard industry was investigated. Fly ash is one of the residues generated in the combustion of coal and generally captured from the chimney of coal-fired power plant. This material is utilized in many industries including cement, soil stabilization, composite etc., but it is not used in paper industry. Three types of fly ashes were collected from Hadong, boryeong and Seocheon steam power plants and we investigated their properties by scanning electron micrographs and particle size distribution. Papers were manufactured with KOCC and fly ashes, and the physical properties such as bulk, tensile strength, internal bond strength and ISO brightness were measured to identify the effects of fly ash on the paper properties.

• Journal of the Korean GEO-environmental Society
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• v.13 no.9
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• pp.5-16
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• 2012

In the case of using the soil materials created by cutting in-situ ground directly without adjusting particle size, it is recommendable to seek the compaction property or material constant required for filling design or density control through indoor test, and many studies on this subject have been carried out during that time. The researches conducted during that time, however, were focused on the mixed materials with different diameters that exist in a natural condition. There has been no study conducted using coal fly ash that is by-product of the thermal power plant that is actively considered as the building materials. Therefore, this study was aimed at implementing compaction test and examining the basic engineering property in order to explore the influence of crushing the particles through compacting the admixture of crushed stone and coal fly ash produced from thermal power plant on its engineering property, and then the impact of the admixture volume of each material on compaction property and material property by conducting the One-Dimensional Compression Test. As result of compaction test, the optimum moisture ratio of coal fly ash was shown to be approx. 23%. As result of compaction test in accordance with the mixed ratio of coal fly ash and crushed stone under the same compaction energy and moisture ratio, dry unit weight tended to drop when the mixed ratio of coal fly ash exceeded 30%, while it reached approx. $1.81gf/cm^3$ when the mixed ratio was 30%. As result of One-Dimensional Compression Test in accordance with the mixed ratio of crushed stone and coal fly ash, the change in void ratio by particle crushing was at the highest level in the case of coal fly ash 100%, while the lowest level in the case of crushed stone 100%. In the case of mixed materials of crushed stone and coal fly ash, compression index was at the lowest level in case of coal fly ash 30%, and therefore this ratio of mixed material was judged to be the most stable from an engineering aspect.