Formation mechanism of silicoferrite of calcium and aluminum in sintering process

To investigate the formation mechanism of silicoferrite of calcium and aluminum (SFCA), the sintering process has been interrupted during the pot test. The column has been dissected and observed by optical microscopy and analyzed using the scanning electron microscope with energy dispersive spectroscopy (SEM-EDS) in the laboratory. The main mechanism of SFCA formation is the reaction of hematite with larnite, calcium rich calcium ferrite, CaO in magnetite, and the vitreous phase in the combustion zone and the high temperature oxidation zone. The high temperature oxidation zone is very important for SFCA formation, especially in the sintering of magnetite.