• Analytical Science and Technology
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• v.15 no.6
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• pp.567-573
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• 2002

The most important and largest commercial outlet of fly ash in Korea is a replacement material of Portland cement in concrete industry. The high level of unburned carbon in ash brings about some malfunctions in concrete. Therefore, fly ash is refined to improve the quality as a concrete additive. In this process, a lot of the residual carbon is produced, and discarded now. In the present study, to find out a valuable outlet of the enriched carbon samples, the basic morphology of residual carbon in fly ash from Boryung power plant was investigated. The unburned carbon characterization included shape, size measurement, and chemical analysis was examined using scanning electron microscope (SEM) and energy dispersive X-ray spectrometer (EDX).

• Resources Recycling
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• v.7 no.1
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• pp.14-19
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• 1998

Tile pl~ysimchemical properties of residual or unburned carbon obtaincd from fly ash were mestigated. The carbon-enrichcd samples were extracted from fly ash by flotalion mcthod. Tnz carbon content and chemical compos~lion of t b recovered carbon sample were analyzed. The ash in the carbon sample was also examined. The unburned carbon characterization included measurement oE sire distibution, sudace area, crystal shuchlre md density.

• Resources Recycling
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• v.8 no.3
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• pp.43-48
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• 1999

The pupose of h s study was to develop a process for removal of unburnzd carbon li-om fly ash by froth flotation. "Carbon zero (C.Z)" develqcd by KIGAM, gave the best results, praduci112 cleaned fly ash containing abom 0.1% FC with 72% yieldBased on the results of batch flotation tests, the pilot-scale tests wcre conducted. The result showed that cleaned fly ash with 0.1% FC could be recovered by about 73% yield.t 73% yield.

• Resources Recycling
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• v.5 no.3
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• pp.44-49
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• 1996

One of the most serious problems in utilizing the fly-ash produced from damcstic coal-firing power plants is lhc unburned-carbon mntained m the fly-ash In this shldy, the effects of fruther and collector an the yield,recuvery,unburnedcarbon rejectiou peiccntage,and process efficiency of product (cleaned fly-ash) wcrc examined when convzntional froth flotation was applied to rejcct the unburned-carbon included in the fly-ash of bituminous coal Alsa,the ash analysis for both thc raw and the clcaned fly-ash was conducted to review the change in thc major elements of fly-ash. Experimental results shawcd lhat tlle rcjectlon oI the unburned-cubon of thc raw fly-ash sample is available upto 92.4% using fiath flotalian and that the putity ol the pmdud(c1eancd fly-ash) attains up to 99.4%.

• Resources Recycling
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• v.8 no.5
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• pp.51-58
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• 1999

The sbdy iwestlgaled ihc propa-ties of Lhe dust\ulcorner rrom fe~~oallomya ~~ufacturTeh. e chemical composition, cornpasitlon material, p d c l e sire md shapes of the bulk dust, sired dust and magnetically separated durl were mvesligaled. As the re\ulcornerulL, we suppose that the dust from &gh Carbon Fenama~~gunesMc anuiact~vingP rocess is not sufiicient as solulce material of Mn because of ale low Mn canlenl (13.5%) and complicaled composition mate~ial. The dust from Bug F!lter or AOD Proccss is mi~inlym ade up of 0.2-2 pm Mn30, (Hausmam~iu)p iutlde in spherical shape and thc Mn content is 63.190.The dust from Cooler of AOD Process is inninly made up of coarse Ca(O1-Or)zM. n,FeyO,, SiO, and fine Mn30d.

• Resources Recycling
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• v.10 no.3
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• pp.14-22
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• 2001

For the recycle of coal fly ash generated from power stations, we developed an electrocyclone system which can separate unburned carbon form coal fly ash, based on the fact that coarse fly ash particles contain higher amount of unburned carbon and unburned carbon particles are charged positively, and pure ash particles are charged negatively on contacting each other. Additionally, guide vanes were installed in the cyclone to control the cut size. Two types of electrode, stick and grid type, were designed to investigate the effect of electrode type. Results show that by introducing an electric field inside the cyclone, the yield increases by 5 to 15e1o. But the content of unburned carbon in the clean ash does not change significantly.

• Plant Journal
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• v.10 no.3
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• pp.34-38
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• 2014

Coal-fired power plants have used oil as fuel for start-up but plasma burner is recently introduced in order to reduce costs. It provides fuel oil-free start-up. But at initial operation of Plasma burner, an increase in unburned carbon remains as still pending issue. Also research and operational standards for this problem are insufficient. In this paper, operating procedure will be proposed through analyzing the impact of unburned carbon in accordance with the Plasma arc current. It is also possible to contribute to the national plant industry by demonstrating economics of Plasma burner in commissioning coal-fired power plants.

• 한국연소학회:학술대회논문집
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• 2006.10a
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• pp.275-275
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• 2006

• Environmental engineer
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• s.159
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• pp.30-37
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• 1999

• Environmental engineer
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• s.160
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• pp.32-37
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• 1999