MONOLITHIC REFRACTORY FOR BLAST FURNACE IRON SPOUT

PROBLEM TO BE SOLVED: To provide monolithic refractory for a blast furnace iron spout in which the wearing rate is lowered, the spout material consumption rate is reduced and the spout repairing frequency is decreased. SOLUTION: The monolithic refractory has a composition containing 50-95 wt.% silicon carbide raw material and 3-30 wt.% in total of magnesium hydroxide fine powder having ≤20 μm average particle diameter and alumina fine powder having ≤20 μm average particle diameter. The ratio of magnesium hydroxide fine powder to alumina fine powder is controlled to (magnesia/alumina (weight ratio))≥0.33, where magnesium hydroxide is expressed in term of magnesia. The monolithic refractory is constituted so that the magnesium hydroxide fine powder and alumina fine powder are heated to form spinel to improve slag resistance of a matrix part except silicon carbide. At least one kind selected from a group comprising a carbonaceous raw material, metal powder, an antioxidant, a hardening agent and a dispersing agent is incorporated in the monolithic refractory. COPYRIGHT: (C)2005,JPO&NCIPI