Self-cementing mechanism of CFBC coal ashes at early ages

Abstract

The self-cementing mechanism at early ages of circulating fluidized bed combustion (CFBC) coal ashes was studied by X-ray diffraction (XRD), infrared (IR) spectroscopy and chemical method. The results indicate that the amorphous phase is predominant in CFBC coal ashes. The polymerization degree of [SiO₄] and [AlO₆] of CFBC desulphurization coal ashes is lower than that of those without desulphurization. The contents of the components with fast hydration rate of CFBC desulphurization coal ashes are significantly greater than those of the ashes without desulphurization. This work confirms that the amorphous minerals with high chemical activity are the main causes of the self-cementing property of CFBC desulphurization coal ashes at early ages.

Keywords

CFBC ashes / self-cementing property / mechanism / hydration / microstructure

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