The fusion characteristics and mineral species of blended coal ash

Conference · Wed Dec 31 04:00:00 EST 1997

OSTI ID:324799

Fan, Li; Ying, Zheng; Jianrong, Qiu; Chuguang, Zheng ^[1]

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1. National Lab. of Coal Combustion, Wuhan (China)

The fusion characteristic temperatures are measured for blended ashes which are a mix of 3 kinds of coal ash at different ratios. XRD is used to study the mineral behavior during heating. The results show that the blended ash fusion characteristic temperatures are not linear with mix ratio. Mineral composition in blended ash at high temperature is consistent with that in the ternary system phase diagram. The main reason why blended ash fusion temperatures are lower than that of a single coal ash is the formation of a low temperature eutectic between the minerals. With blended-coal being more and more utilized for coal combustion and gasification, the slag-bonding caused by their inorganics becomes a more serious problem, which directly influences the safe operation of boilers and gasification furnaces. The behavior of minerals in coal-ash has been widely studied for a single coal ash, and also analyzed with the ternary systems phase diagrams. However, it is rare to do so for blended-coal ash. In this paper, the authors select 3 kinds of single coal ash (Songmuping coal, Huangling coal, and Shenmu coal) to mix into 2 kinds of blended-coal ash, and measure blended-coal ash fusion characteristic temperatures and analyze the ash by XRD. The results are analyzed and discussed using the phase diagram of the ternary system SiO{sub 2}-Al{sub 2}O{sub 3}-CaO. In addition, the authors try to explain blended-coal-ash fusion characteristic from the viewpoint of micro-mineralogical. These results should be helpful for forecasting the blended-coal slag-bonding mechanism.

• OSTI ID: 324799
• Report Number(s): CONF-970931--
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
ASHES
COAL
COMBUSTION KINETICS
FORECASTING
MINERALOGY
MIXTURES
PHASE STUDIES
SLAGS