The kiln lining used in alumina rotary kiln is to select different refractory bricks according to different sections, analyze the use of the lining, put forward requirements for the performance of refractory materials in each section, and improve the service life of the kiln lining. During the production process, the kiln was stopped and bricks were replaced due to the explosion and falling off of the clay refractory kiln lining in the preheating decomposition zone, which affected the operation cycle of the rotary kiln. This is because the chemical composition of the clay refractory products fluctuated greatly, so their performance indexes changed greatly.
In addition, different brick materials, different manufacturing methods and changes in firing temperature can also cause great fluctuations in performance. Therefore, on the premise of improving the service life of fired brick, the service life of alumina rotary kiln lining is shortened and the thermal conductivity of clay refractory products is large, which is easy to cause a waste of energy due to the mismatching of decomposition zone.
Some customers invest in alumina rotary kiln to calcine clay bricks. However, due to the large proportion of clay bricks and high thermal conductivity, some adverse factors are brought to the kiln equipment. Due to the high radiant heat, the lubricating oil in the gear box smokes and catches fire during operation, which may lead to production stoppage or kiln deformation and scrapping. Insulating refractory bricks and refractory fibers can be added between the shell of the clinker kiln and the inner brick.
However, due to the low strength of these thermal insulation and refractory materials, when the ignition is started, the alumina rotary kiln shell not only cannot operate synchronously with the inner village bricks, but also seriously rubs the thermal insulation bricks, resulting in a large area of falling off of the inner village bricks and having to be repaired.
Later, it was changed to self-made asbestos insulation brick, which achieved good results in reducing the external temperature of the cylinder, the full operation of the whole kiln and the improvement of product quality. However, the asbestos insulation brick and the heavy working layer cannot be well combined, which causes the insulation layer and the working layer to fall off during the operation, making the lining loose and lose bricks. Although the purpose of energy saving is achieved, the construction is troublesome and the construction period of double-layer masonry is long, so it will be terminated with the shortening of the construction period.