Corrosion of zircon-modified andalusite refractory brick by materials in cement kiln preheater.

The study of the zircon-modified andalusite (Al2SiO5-ZrSiO4) refractory material corrosion in the corroding medium of cement kiln preheater was carried out at the temperature of 1000±100°C. The main corrosive agents in cement kiln preheater were agents in solid, liquid and gaseous form. Gaseous or liquid corrosion of andalusite-zircon refractories was related mainly to K+/K2O attack. The new phases such as K2O-Al2O3-SiO2 compounds i.e. kalsilite (KAlSiO4) and leucite (KAlSi2O6) were formed as a result of chemical reaction between potassium and Al2SiO5. Calcium oxide from the solid particles of a hot kiln meal reacted with Al2SiO5 grain and formation of gehlenite Ca2Al2SiO7 took place. The corroded samples were examined using X-ray fluorescence (XRF), X-ray powder diffraction (XRD) and Scanning Electron Microscopy with X-ray microanalysis (SEM/EDS).

Author: D. Madej, J. Szczerba

Section: Refractories

Keywords: corrosion, preheater, cement kiln, andalusite refractories, zircone