Environment-friendly energy-saving semi-light-weight refractory castable for iron ladles

The invention discloses an environment-friendly energy-saving semi-light-weight refractory castable for iron ladles, which is prepared by mixing 35-37% of superfine high bauxite, 25-28% of brown fused alumina, 14% of silicon carbide, 10% of light-weight mullite, 3-4% of silicon dioxide micropowder, 3-7% of aluminum oxide micropowder and 5% of calcium aluminate cement used as raw materials with a composite dispersing agent which accounts for 0.25 wt% of the raw materials. All the raw materials are free of organic matters, heavy metals and other harmful elements, and thus, the refractory castable has the characteristics of no injury to the human body and no environment pollution. All the raw materials adopt scientific and reasonable particle size distribution to optimize the matrix composition, and a proper amount of composite dispersing agent can effectively enhance the workability of the castable. The added light-weight mullite has uniform microstructure, has the advantages of favorable high temperature resistance, favorable heat insulation property, higher strength and favorable scour resistance, and is capable of enhancing the durability of the integral castable and prolonging the service life of the castable.