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이재근;김장우;구재현;신진혁;김성찬;신희수;황유진
- 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%.
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Kim, Deuck-Mo;Mun, Kyung-Ju;Soh, Seung-Young;Soh, Yang-Seob
- Proceedings of the Korea Concrete Institute Conference
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- 2008.11a
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- pp.669-672
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- 2008
bottom ash has difficult in recycling because of low activity and unburned carbon. so our study was control the unburned carbon for improvement of bottom ash. unburned carbon was controlled by distribution. The result of distribution is good that unburned carbon of bottom ash decrease in 4.5%. when we are replace bottom ash with OPC to 10$\sim$30%, specimens strength is decrease. but mix of controlled bottom ash revealed that it's strength increase 6% better than uncontrolled bottom ash.
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이정은;이재근
- Resources Recycling
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- v.9 no.6
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- pp.36-44
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- 2000
Fly ash was composed of the unburned carbon and mineral particles. The former was able to attach on the bubbles, while the latter was not. Therefore, it was possible to separate the unburned carbon and the mineral from fly ash using the froth flotation process. This study was carried out to evaluate the separation efficiency as a function of the ny ash particle properties in the column flotation. Separation efficiency was analyzed for various size fraction of -38 fm,38~125 fm and 1125 W, and for various fly ash samples containing 7, 11, and 20 wt% unburned carbon. For the size fractions of -38 fm containing 7 wt% unburned carbon, separation efficiency was 86ft, whereas separation efficiency was found to be 74% for the size fraction of +125$\mu\textrm{m}$ containing 20 wt% unburned carbon. The results indicated that separation efficiency increased with the decrease in the particle size and the unburned carbon content of the fly ash.
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