The compaction quality standards for the refractory lining of an alumina rotary kiln are as follows:

(1) When casting the refractory lining of an alumina rotary kiln, ensure that expansion joints are provided as required.

(2) The castable refractory should be vibrated to ensure compaction. When using an immersion vibrator, the thickness of the cast layer should not exceed 1.25 times the length of the vibrator’s working section, and the distance between the vibrator insertion points should not exceed 1.5 times the vibrator’s radius of action. When using a plate vibrator, its thickness should not exceed 200 mm.

(3) The casting of the rotary kiln refractory lining castable should be continuous. The next layer of castable refractory should be cast before the previous layer sets. If the interval exceeds the setting time, it should be treated according to the requirements for construction joints.

(4) The curing of the castable refractory should be carried out according to the methods specified for all grades. During the curing period, the rotary kiln refractory lining castable should not be subjected to external forces or vibrations.

(5) Non-load-bearing formwork should only be removed when the strength of the castable refractory ensures that its surface and edges will not be damaged or deformed during demolding; load-bearing formwork should only be removed after the castable refractory has reached 70% of its design strength.

(6) The surface of the rotary kiln castable refractory should be free from defects such as spalling, cracks, and holes.

(7) On-site sampling of the castable refractory should be conducted, with 20 cubic meters per batch for testing; any batch less than this number should also be considered for testing.