Behaviour of Olivine Refractories at High Temperature: Agglomeration in a Fluidized Bed Reactor
CNRS, CEMHTI UPR3079, Univ. Orléans, 45071 Orléans/France
Revision 31.05.2013, 31.09.2013
Volume 6, Issue 1, Pages 95 - 98
Abstract
Natural olivine is an important refractory raw material because of its abundance in the earth’s crust. It is composed of solid solution of magnesium silicate with forsterite Mg2SiO4 configuration and iron silicate in a small amount of fayalite Fe2SiO4. This raw material is mainly used in different refractory applications. For instance, it is used in fluidized bed reactors to produce a high calorific fuel-rich synthesis gas (CO + H2) from biomass. However, in gasification/combustion reactor, the agglomeration of the fluidized bed may occur due to the reactions between olivine and biomass ashes. Additionally, olivine undergoes phase transformations (dehydration and oxidation) during calcination at high temperature, which significantly affect the chemical processes. Among these phase transformations, magnetite is produced and contributes to the reactivity of refractories as well as to the particle agglomeration with biomass ashes.
Keywords
olivine refractory, fluidized bed, Raman spectrometry, in situ XRD
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