CHARGE AND METHOD FOR PRODUCING MULLITE-SILICA REFRACTORY ARTICLES Russian patent published in 2017 - IPC C04B35/185 C04B35/626 

FIELD: metallurgy.

SUBSTANCE: charge for producing mullite-silica refractory comprises mullite-corundum chamotte as a grain component with Al₂O₃ content more than 80 wt %, Fe₂O₃ not more than 2.0 with water absorption 2-6.0% and kaolinic chamotte with Al₂O₃ content more than 40 wt. %, Fe₂O₃ not more than 1.5 with water absorption not more than 3.5%, and semi-acid refractory clay as a binder containing wt %: Al₂O₃ 20-28, SiO₂ 62-65, Fe₂O₃ 1.4-1.8, Na₂O 0.1-0.4, K₂O 1.2-1.4 with the following content of components, wt %: mullite-corundum chamotte, 30-40; kaolin chamotte, 35-40, the binder 24-35. The method for producing mullite-silica refractory includes preparing the mixture of ground chamotte, moistening with a slip, introducing the refractory clay, pressing the produced mass with release of air: first release after applying specific force of 0.7-1.0 kN/cm², stripping after the first release of air for 3-5 seconds, the second release of air after applying the force of 1.0-1.5 kN/cm², then pressing at specific force of 4-6 kN/cm², drying and annealing at 1290-1320°C. The mullite-silica refractory has porous structure with pore size distribution, %: 130-100 microns to 0.7; 100-20 microns 21-34; 20-10 microns 24-40; less than 10 microns 35-50; less than 5 microns 20-35.

EFFECT: production of mullite-silica refractory with low open porosity, having sufficient strength and low cost.

5 cl, 1 dwg, 4 tbl