How should dryout heating of cold wall refractory be conducted?

Heating dryout for cold wall refractory should be conducted from the refractory hot face because this method promotes more uniform heating and prevents the formation of thermal stress or cracking that can occur if the cold face is heated directly. When heat is applied to the hot face, it allows the moisture within the refractory to migrate towards the cooler areas, ensuring that the drying process is efficient and that the refractory material reaches the appropriate temperatures gradually. This approach enhances the integrity of the refractory material, allowing it to achieve its designed performance and durability.

Maintaining the correct temperature gradient is crucial during the dryout process, as rapidly heating from the cold face can lead to uneven temperatures and potential failure of the refractory. This is why heating from the hot face is generally recommended in industry practices.