The production process of high-alumina bricks is similar to that of multi-clinker clay bricks, but the difference lies in the higher proportion of clinker in the raw materials, which can reach 90-95%. The clinker needs to be graded, sorted, and screened to remove iron before crushing, and the firing temperature is higher; for example, high-alumina bricks of grades I and II are typically fired at 1500-1600℃ in tunnel kilns.
Chinese production practice has proven that strict sorting, grading, and storage of high-alumina clinker before crushing, along with the use of a method of fine grinding together with bauxite clinker and binding clay, can improve product quality.
High-alumina bricks are mainly used for lining blast furnaces, hot blast stoves, electric furnace roofs, blast furnaces, reverberatory furnaces, and rotary kilns. In addition, high-alumina bricks are widely used as checker bricks in open-hearth furnaces, stoppers in casting systems, and nozzle bricks. However, high-alumina bricks are more expensive than clay bricks; therefore, they are not necessary where clay bricks can meet the requirements.
