• Resources Recycling
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• v.20 no.6
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• pp.71-77
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• 2011

Raw mix of molten clinker was fabricated using blast furnace slag as starting material. Raw mix was melted at 1620 for molten clinker fabrication. Color and mineral composition of molten clinker was investigated by XRD and colorimeter. It was found that the molten clinker contains alite and belite equivalent to OPC clinker mineral and shows higher whiteness value than that of OPC. Whiteness of the molten clinker decreased with LSF and SM. Also the whiteness value of the slag cement using molten clinker was higher than that of common slag cement.

• Journal of the Korean Ceramic Society
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• v.48 no.6
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• pp.589-594
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• 2011

Raw mix of molten clinker was fabricated using blast furnace slag as starting material. Raw mix was melted at 1620$^{\circ}C$ for molten clinker fabrication. It was found that molten clinker contained alite and belite equivalent to OPC clinker mineral by optical microscope and SEM. The size of alite was 10~50 ${\mu}m$ and that of belite was 20~80 ${\mu}m$. This result thought to be attributed low $Al_2O_3$ content and cooling condition. Interstitial phase increased with blast furnace slag content and gehlenite was formed by the condition of LSF and SM. So raw mix with 27~41% blast furnace slag could be converted into cement clinker by appropriate choice of melting andcooling methods in this study.

• Journal of the Korean Ceramic Society
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• v.35 no.12
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• pp.1301-1307
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• 1998

For dolomite clinkers used as stamp materials the corrosion behavior of those by molten steel was investigated in therange of temperatures between 1550$^{\circ}C$ and 1600$^{\circ}C$ IN hot face the dicalciumferrite of magnesioferrite and dicalciumferrite formed within dolomite clinkers was preferentially dissolved into molten steel and the protective layer of magnesioferrite was formed. For dolomite clinker without Fe2O3 magnesioferrite maintained the skeleton of MgO while the skeleton of CaO disappered bythe formation of dicalciumferrite and it existed as grain boundary phases of magnesioferrite. For dolomite clinker with Fe2O3 was diffused into hot face by the decomposition of dicalciumferrite. With increasing temperature of molten steel the formation depth of dicalciumferrite was increased and the magnesioferrite layer in hot face was decreased for dolomite clinker without Fe2O3 while the layer thickness and grain sizes of magnesioferrite in hot face was decreased for dolomite clinker without Fe2O3 while the layer thickness an grain sizes of magnesioferrite in hot face was increased due to the increment of the decomposition reaction of dicalciumferrite for dolomite clinker with Fe2O3.

• Journal of the Korean Society of Combustion
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• v.8 no.2
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• pp.34-40
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• 2003

Analyses for concentration, surface phenomena, and crystal structure were performed to identify the causes of clinker formation in three type of pulverized coal fired boilers. Some clinkers had partially molten surface and more CaO and $Fe_2O_3$ as compared with fly ash, and the major crystalline phases identified in the clinker were mullite and quartz. Clinkers were formed in high temperature zone of the boiler according to the identification of mullite by XRD. Free $SiO_2$ in sand combined with K, Na and Ca in limestone served as a fluxing agent to form clinkers in a circulating bed boiler.

• Journal of the Korean Society for Heat Treatment
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• v.36 no.1
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• pp.22-32
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• 2023

In general, when scrap is dissolved in an electric arc furnace, the amount of electric furnace steel dust (EAFD) generated is about 1.5% of the scrap charge amount, and the electric furnace steel dust collected by the bag filter is charged into the Rotary Kiln or Rotary Hearth Furnace (RHF), and the zinc component is recovered as crude zinc oxide, at which time a clinker of Fe-Base is generated. In this research, first, for the efficient resource conversion of electric furnace steel dust, a reduction and roasting experiment was conducted and the reaction kinetics was examined. As a result of the experiment, it was observed that the reduction and roasting reaction was actively conducted in the range of 1100~1150℃, and melting occurred in the range of 1250℃. In the past, this clinker was widely used as a roadbed material for road construction and an Fe-Source for cement production, but in recent years, it has been mainly reclaimed due to strengthening environmental standards. However, landfill treatment is by no means a desirable treatment method due to environmental pollution caused by leachate, expensive landfill costs, and waste of Fe resources. Therefore, in order to more actively recycle the Fe component in the clinker, first of all the clinker was pulverized into an optimal particle size, and anthracite and binder (starch) were added to the magnetic material obtained by specific gravity and magnetic separation for briquet. As a experimental results, it was possible to efficiently separate clinker as Fe component and other slag component by specific gravity and magnetic force. As a results of loading and dissolving the manufactured briquet clinker in an electric arc furnace, it was observed that the unit of power and production yield were clearly improved and the carbon addition effect in molten metal was also somewhat.

• Analytical Science and Technology
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• v.13 no.1
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• pp.5-11
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• 2000

During the commissioning period in Tonghae thermal power plant which is the largest circulating fluidized bed boiler in the nation, a considerable amount of clinker was formed at FBAC and seal pot. Various attempts, for example, concentration analysis, surface phenomena, thermal characterization, and crystal structure of ash, bed sand, limestone, clinker, and mixture of each gradients have been studied to identify the causes of clinker formed in circulating fluidized bed boiler. As the results, the characterization of black particles in which separated from the clinker is more similar to that of bed sand, on the other hand, white particles are more similar to ash. In addition, the sintering temperature of sand is over $1,200^{\circ}C$ and this temperature was decreased as limestone is added to bed material. The cause of clinker was proved that ash was sticked to molten or sintered sand or limestone in the area of high temperature in the circulating system.