Modelling of the Fly Ash Particle

In general, majority of the fly ash particles have been reported to be spheroids in shape and efforts have been made to establish their chemical and mineralogical composition [1-5]. The outer most surface of the ash particle is different than the inner core, in terms of its reactivity with NaOH. In order to know more about the intra-particle heterogeneity of a fly ash particle, it can be picturized as depicted in Fig. 4.1. 

It can be noticed that the smooth outer boundary (i.e., reacting surface) of the spherical particle (i.e., cenospheres) is mostly composed of the glassy material, which has been reported to exhibit comparatively higher reactivity than the Quartz and MuUite, embedded in the inner portion of the fly ash particle [5]. 

Outer most smooth layer of aluminosilicate glass (i.e., SiO2 70%, others =10%] 

Inner most core of MuUite (3Al203.2Si02) 25% [Si 27%, Al 70%] 

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