MECHANICAL ACTIVATION OF FLY ASH: PHYSICAL, MINERALOGICAL AND MORPHOLOGICAL CHARACTERIZATION OF GROUND FLY ASHES

Year 2019, Volume: 20 , 66 - 76, 16.12.2019

Sedef Dikmen , Zafer Dikmen Gülgün Yılmaz , Seyhan Fırat

https://doi.org/10.18038/estubtda.637927

Cited By: 1

Abstract

In this study, physical, mineralogical and morphological
characteristics of mechanically treated fly ashes are investigated. The
compositional analysis of the raw fly ash was determined using X-ray fluorescence
(XRF) technique. The XRD patterns reveal that the main phase quartz along with
mullite and anhydrite. The raw fly ash was also wet ground using a laboratory
mill, for several different times (from 2 to 16 hours) in order to examine how
the grinding increases the activity of the fly ash. The ground fly ash was
characterized for (i) particle size distribution: laser diffraction method,
(ii) specific surface area: BET-method, (iii) crystalline structure: X-ray
diffractometer, and (iv) morphology of particles: scanning electron microscope.
According to physical characterization, fineness increasing of samples with
grinding time was observed, but loss of effectiveness occurred for grinding
time longer than 12 hours. In addition, the unmilled fly ash showed lower
specific surface area, due to the presence of cenospheres in the original fly
ash. Only a little change in crystalline structure of fly ashes was observed
when grinding and
there were changes in the area and height of each diffraction peak.

Keywords

Fly Ash, Microstructure, XRD, SEM

Thanks

The authors are thankful to Mr. Orhan ÇETİN, from Ceramic Research Centre for XRD and XRF analysis, and to Mr. Naci SARAÇOĞLU from ATOMIKA Teknik Trade and Limited Company.

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