The use of technogenic raw materials in high-alumina chamotte production

Abstract

The aim of this project is to develop the mass composition and the technology for producing high-alumina chamotte with an Al2O3 content of 65–85% based on technogenic raw materials – fine corundum dust formed during grinding of fused corundum. Finely dispersed corundum powder contains 93–95% Al2O3 is a by-product and can be used to obtain high-alumina chamotte. The parameters of high-alumina chamotte molding were determined. For the composition of the masses with Al2O3 content of 65% the molding moisture is 5–7%, with a pressing pressure of 15–20 MPa; with Al2O3 content 75% – moisture is 5–7%, pressing pressure is 10 MPa; with Al2O3 content 85% – moisture is 9%, pressing pressure is 15–20 MPa. Water absorption of chamotte after firing at 1700°C is 12–15%. The phase composition of chamotte with Al2O3 content: 65% – corundum (35–38%), mullite (46–50%), thialite (up to 4%), cristobalite (6–8%); 75% – corundum (43–50%) mullite (45–47%), thialite (up to 4%); 85% – corundum (68–71%), mullite (24–27%).