# 유동층(流動層) 연소기(撚燒器)로 부터 발생(發生)된 석탄(石炭) 비산(飛散)재를 이용(利用)한 인공경량골재(人工輕量骨材) 제조(製造)

• Kang, Min-A (Department of Materials Engineering, Kyonggi University) ;
• Kang, Seung-Gu (Department of Materials Engineering, Kyonggi University)
• 강민아 (경기대학교 신소재공학과) ;
• 강승구 (경기대학교 신소재공학과)
• Accepted : 2011.02.01
• Published : 2011.02.26

#### Abstract

The spherical artificial aggregates (AAs) with a diameter of 8 mm, which contains fly ashes discharged from the fluidized bed combustion in a thermal power plant and clay were manufactured by direct sintering method at $1050{\sim}1250^{\circ}C$ for 10 minutes. The effect of fly ash contents on the bloating phenomenon in the AAs was analyzed. The AAs containing fly ash of the amount under 50 wt% showed the black-coring and bloating phenomena. The AAs containing fly ash of the amount over 5Owt%, however, the specific gravity was increased and the color of specimens fully changed to black. These color change phenomena were caused from the formation of FeO by the reduction reaction of almost $Fe_2O_3$ component by the excessive reducing atmosphere formed simultaneously with the rapid emission of the gases generated from the high contents of unburned carbon of with increasing the added fly ash amount. Specific gravity was decreased as fly ash contents increased in the case of sintering at the same temperature condition. Water absorption of all specimens except of the specimens containing 10 wt% fly ashes decreased with increasing sintering temperature. These were because a liquid phase was formed as the increasing the sintering temperature. In the case of the specimens manufactured in this study containing fly ashes discharged from the fluidized bed combustor in a the thermal power plant and 10~90 wt% of clay, the specific gravity was 0.9~1.8 and the water absorptivity was 8~60%, therefore it is considered that those results can be applied to the light or heavy aggregates.

#### References

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#### Cited by

1. Application of Powdered Waste Glasses and Calcium Carbonate for Improving the Properties of Artificial Lightweight Aggregate Made of Recycled Basalt Powder Sludge vol.14, pp.3, 2014, https://doi.org/10.5345/JKIBC.2014.14.3.230
2. Grinding Effects of Coal-Fired Pond Ash on Compressive Strength of Geopolymers vol.23, pp.6, 2014, https://doi.org/10.7844/kirr.2014.23.6.3