Study And Application On The Castable For The Outlet Of The New Style Dry Cement Klins

From the beginning of the 21th century, the development of the new style dry cement of our country is very quickly, the output of the new dry cement in 2007 has increased to 55% of the total output of cement. In burning system of the new dry cement, the burning system's work ratio and clinker's production were restricted directly by the quality of the refractory for outlet.Now, the castables were often used as outlet's liner refractories on the new dry cement kilns in our country, and the chief factors that can affect castable's life are wear, thermal shock, chemical erosion, mechanical stess damaging and high tempriture melt etc. The general life of the castables used in the outlet of large new dry cement kilns is 4-6 months.We want to study and manfacture a new castable that it's life will reach 11-12 months. We use super alumina, activatedα-Al₂O₃ mullite powder, u f - SiO₂ mullite powder, CA cement, SiC powder and corundum powser as the raw meterials, researched the affection of the sintering reaction in the matrix and the addition and grain size of SiC powder to the properties of the castable. The experimental result is : use activatedα-Al₂O₃ mullite powder, u f - SiO₂ mullite powder, CA cement and corundum powser as the matrix, the low tempriture strength and the strength after heated at medium and high tempeiture are very satisfied, and there are obvious sintering reaction after 900℃heated, we believe the product after sintering reaction include A₃S₂, CAS₂ and aluminate calcium etc. The thermal shock resistance of the castable is satisfied when add 6% and 0.099 mm SiC powder in matrix, the SEM of the sample after heated at 1350℃×3h show: around the residual section after SiC oxidated formed surrounding split, and residual SiC grain take affect as the enhancement grain, and the surrounding split increase the thermal shock resistance of the castable. The new castable had been used on the outlets of the 2500t/d production lines in the country and the results showed it's life achieve or above the desired goal.