What Castables are used for Furnace Lining?

The selection of furnace lining castables mainly depends on many factors such as the type of furnace, operating temperature, chemical erosion, mechanical stress, etc. Different furnace linings require different materials of refractory castables due to their different working conditions.

First, consider the operating temperature of the furnace. For example, the normal operating temperature of the heating furnace is generally 1250-1350℃, but the lining castable sometimes has to withstand high temperatures of 1400-1500℃. Therefore, refractory castables not only require sufficient high-temperature refractory performance and thermal shock resistance but also should have excellent resistance to high-temperature airflow erosion and smoke erosion. In this case, castables with special-grade alumina clinker, three-stone minerals, etc. as the main raw materials, combined with -Al2O3 micro powder, silicon micro powder as binder, and silicon micro powder as auxiliary binder can be selected. Such materials have excellent high-temperature performance and good thermal shock stability, which are suitable for furnace linings.

Secondly, the chemical erosion of the furnace should be considered. For example, after the iron ore powder, fuel, and flux sintered in the ignition furnace are mixed, they will adhere to the furnace wall at a certain temperature, react with the refractory castable of the furnace lining, and form chemical erosion. Therefore, when selecting the lining of the ignition furnace, the slag erosion resistance of the refractory castable must be considered. Mullite composite refractory castable is very suitable for the lining of the ignition furnace because of its strong resistance to high temperature, erosion, and erosion.

In addition, the wear conditions of different furnace parts are also different. For example, the wear of the CFB boiler lining is mainly manifested as erosion wear, which is affected by multiple factors such as thermal stress and thermal shock, solid material erosion, and changes in the properties of the refractory castable. Therefore, when selecting the refractory castable for the CFB boiler lining, its wear resistance and erosion resistance need to be comprehensively considered.

In short, the selection of lining castables should comprehensively consider multiple factors such as the operating temperature, chemical erosion, and mechanical stress of the furnace. In practical applications, it is also necessary to select suitable refractory castables according to the working conditions and requirements of the specific furnace.