• Proceedings of the Korea Concrete Institute Conference
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• 1998.04a
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• pp.95-98
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• 1998

Fly ash is glassy dust collected from coal fired power plant. Recently, much research for fly ash conducted in Korea and fly ash is a valuable material especially when it used in high strength, high flowable, high durability concrete. But it varies with coal source, coal grinding and boiler conditions. Therefore, it is important that quality control of fly ash itself to get high quality concrete. In this study, over 20 samples of Poryong and Samchonpo fly ashs are tested and analyzed. The physical, chemical properties of fly ash and their relationships are investigated and it can be applied to quality control of concrete.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.73.2-73
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• 2003

Typical whiches broom symptoms caused by phytoplasma were observed in Ash (Fraxinus rhynchophylla Hence) in Korea. The symptoms were showing abnormally small leaves, short internodes, and proliferation of shoots. Fluorescence and electron microscopy of leaf midribs revealed phytoplasma positive DAPI fluorescence and numerous phytoplasma bodies localized in the phloem sieve tubes. Phytoplasma DNA of 1.8 Kb was detected consistently from all symptomatic samples by the amplification of phytoplasma DNA with the phytoplasma specific primer pair Pl/P7. But no phytoplasma DNA was detected in healthy ash seedlings. Based on sequence analyses of an amplified region, this phytoplasma is closely related to Eqilodium phyllody, Mulberry dwarf, and Aster yellows phytoplasmas with the homology of 99.95 ％, 99.79 ％ and 99.78 ％, respectively, This phylogenetic analyses indicate that ash witches broom phytoplasma but is evidently distinct from the ash yellows group 16SrⅦ and should be classified into the Aster yellows group 16SrⅥ.

• Journal of Environmental Science International
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• v.26 no.12
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• pp.1333-1339
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• 2017

Coal-fired power plants emit various Particulate Matter(PM) at coal storage pile and ash landfill as well as the stack, and affect the surrounding environment. Field Emission Scanning Electron Microscopy and Energy Dispersive X-ray analyzer(FE-SEM/EDX) were used to develop identification factor and the physico-chemical analysis of PM emitted from a power plant. In this study, three samples of pulverized coal, bottom ash, and fly ash were analyzed. The pulverized coal was spherical particles in shape and the chemical composition of C-O-Si-Al and C/Si and C/Al ratios were 200~300 on average. The bottom ash was spherical or non-spherical particles in shape, chemical composition was O-C-Si-Al-Fe-Ca and C/Si and C/Al ratios were $4.3{\pm}4.6$ and $8.8{\pm}10.0$. The fly ash was spherical particles in shape, chemical composition was O-Si-Ai-C-Fe-Ca and C/Si and C/Al ratios were $0.5{\pm}0.2$ and $0.8{\pm}0.5$.

• Journal of Environmental Impact Assessment
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• v.9 no.1
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• pp.1-11
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• 2000

An environmental geochemical survey of heavy metal distribution in marine surface sediments around the ocean of Samcheonpo coal-fired power plant was conducted to investigate the possibility of coal-ash leakage from ash pond and the associated heavy metal pollution in sedimental deposits due to the operation of the coal-fired power plant. The X-Ray Diffractometry (XRD) analysis showed that the main leakage point of coal-ash was limited to a single site of the first ash pond. It also appeared that the amounts of organic carbon and metal elements were positively correlated to the grain size distribution, and that Co, Cr, Cu, Fe, Ni, and Zn were bounded to organic ligands. However, the distributions of Cd, Hg, and Mn did not have any significant correlation with the sediment grain size and organic matters. In particular, the distribution of Cd appeared to be affected by the concentration of the carbonate materials in the study area.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.11a
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• pp.99-100
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• 2015

Significant amount of bottom ash has been produced in the power plant located at southeast region of Korea, but those were abandoned in the pond site without any treatment. In these days, there is a strong move to enforce environmental regulations to protect surrounding nature, a lot of pressure is given to the power plant industry to remove hazardous chemicals from their waste material before landfill or site storage. The overall objective of this research is to separate hazardous chemicals from the bottom ash, and use it safely as sustainable construction material. In this specific study, magnetic separation of bottom ash was applied, and used as a fine aggregates to make mortar specimens. According to the results, it was found that the use of bottom ash decreased 28-day compressive strength. However, using non-magnetic bottom ash provides best results in terms of thermal conductivity, showing strong possibility to be used as heat insulating material.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.24 no.4
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• pp.526-532
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• 2000

Recent studies have been directed toward obtaining a better understanding of the application of electrostatic precipitators to collect fly ash particles produced in a coal-fired power plant. Electrical resistivity can be described as the resistance of the collected dust layer to the flow of electrical current and is an important property for the collection efficiency in the electrostatic precipitator. In this paper, fly ash resistivity as a function of temperature up to $450^{\circ}C$ has been experimentally investigated using the resistivity meter consisted of the movable electrode, dust cup, and furnace. Resistivity was found to increase with increased temperature up to $200^{\circ}C$ due to the reduction of water concentration and then gradually decrease with increased temperature due to the activation of electrons. As the resistivity of fly ash in the flue gas temperature of $150^{\circ}C$ was measured >$10^{10}$ ohm cm, the efficiency of fly ash removal in the electrostatic precipitator might be expected to be low due to back-corona phenomenon. Flue gas conditioning in the electrostatic precipitator to reduce the resistivity of fly ash as required.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• v.10 no.S_2
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• pp.89-95
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• 2001

The solidification and leaching characteristics of cyclone ash collected from an industrial incineration plant were investigated. Cement and calcium hydroxide were used as the solidifying materials. The leaching characteristics of the solidified cyclone ash were found to vary depending on both the quantitative and the qualitative aspects of the solidifying materials. Except for copper and lead, all the heavy metal ions in the leachate of the solidified material composed of 10~20 % cement or 10~20 % calcium hydroxide were found to be within their standard limit. Moreover, all the heavy metal ions were also observed to be within satisfactory limits in the leachate obtained from the solidified material composed of 30 % cement or 30 % calcium hydroxide. Therefore, to satisfy the standard compressive intensity and permissible limits of heavy metal ions leached from solidified material, it would appear that a 30 % proportion of either additive in the solidification product can meet the required standard for the leachate. The cost of solidifying cyclone ash per ton for ash-30 % cement and ash-30 % lime was calculated as 26,750 and 26,070 won, respectively. Accordingly, significant reduction in the waste toxicity and mobility as well as an improvement in the engineering properties of the solidified products were successfully achieved.

• Journal of the Korean Society of Industry Convergence
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• v.22 no.1
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• pp.55-60
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• 2019

Growing plant in potting media without soil is known as Soilless cultivation. This method is used mostly in greenhouse cultivation to increase horticultural commodities production. Peat moss is commonly utilized as potting media substrate because of its characteristic. However, peat moss price is high because of the quantity of peat moss in nature has been decreased. Recently, most of the research is conducted to find the alternative growing medium to cultivate horticulture plant in potting media. Perlite and rice husk ash were mentioned that had a potent as alternative growing media for seasonal plants to increase agriculture production due to the lack of production area. This research aims to determine the growth of in rice husk ash, perlite and peat moss as growing substrates. The method used was the soilless cultivation. The chinese cabbage was planted in the pot with perlite media, rice husk ash media, and peat moss media. The chinese cabbage was measured after 35 days after planting. The result showed that peatmoss was more potentials in chinese cabbage growth performance than rice husk ash and perlite. Peat moss had the significant result of every research parameters such as plant height, plant weight, number of leaves, plant diameter, root length, and root weight. The best alternative for cultivation chinese cabbage without substrate based on this research was peat moss then rice husk ash and perlite.

• Journal of Energy Engineering
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• v.11 no.1
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• pp.67-73
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• 2002

The carbon-in-ash system for simultaneously monitoring the unburned carbon in fly ash produced in a coal-fired power plan is designed and evaluated using the domestic fly ash produced in the coal-fired power plant. Real time monitoring is very important to control the combustion of the boiler in the coal-fired power plant and the purification system for fly ash recycling. The carbon-in-ash system based on the capacitance measurement consists of a LCR meter, a duct collector and an electrode cell. The capacitance of fly ash increases linearly with increasing fly ash carbon contents. The water content in fly ash plays an important role on the ash capacitance. The empirical equation for predicting the content of unburned carbon in fly ash produced in the domestic Boryung, Hadong and Samchenpo coal-fired power plants can be derived in the range of carbon content 0-20%.

• Korean Journal of Soil Science and Fertilizer
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• v.28 no.4
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• pp.334-339
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• 1995

To investigate the utilization of fly ash in agriculture, sorghum [Sorghum bicolor(L.) Moench] was used as the test crop. Soil was treated in pot experiments with anthracite and bituminous fly ash at 5 levels of 0, 6, 12, 18, and 24%, respectively. Growth status in terms of plant height and the number of nodes was improved in the order of bituminous treatment > anthracite treatment > control. The increment of fly ash had a positive effects on plant growth in both anthracite and bituminous treatment. The ratio of the senescent leaves to the all leaves during the maturing period was higher in fly ash treatments than in the control. As increasing the fly ash treatment, the ratio of senescent leaves was increased. Total yield was higher in the order of bituminous treatment > anthracite treatment > control. Grain yield also was higher in fly ash treatment than in the control. Bituminous fly ash treatments were more favourable in grain yield than anthracite. The increment of up to 12% fly ash to soil increased grain yield in both anthracite and bituminous. Application of bituminous fly ash could be recommended due to the fact that high pH of soil is favorable for growth of sorghum.