Cement Energy Environment

64 The introduction of this excessive concentration of alkali salts, sulphates, chlorides in the kiln system, hampers the overall performance of refractories and causes a lot of coating formation on refractory surface and pre- To minimize these challenges when using alternative fuels, the refractory used should be of such quality that it does not allow these chemicals to react and infiltrate the inside matrix of the refractory. To check this chemical inertness and infiltration of salts in the refractory, HASLE does a refractory cup test in their own laboratory. A cup of castable is made and subsequently coating collected from a cement plant site or different combinations of salts like (Na 2 SO 4 , K 2 SO 4 , This is possible by using high grade raw materials to manufacture refractory and by maintaining a very low open porosity, which will not allow salts to react with and infiltrate the refractory. 3Al 2 O 3 .2SiO 2 + Na 2 SO 4 /K 2 SO 4 / NaCl/KCl => K 2 O·Al 2 O 3 ·2SiO 2 / K 2 O·Al 2 O 3 ·4SiO2/ Na 2 O·Al 2 O 3 ·2SiO 2 Alkalis from Feed + Sulphates & Chlorides from AF => Alkali Sulphates + Alkali Chlorides (CaO, K 2 O, Na 2 O) (SO 3 , Cl) (Na 2 SO 4 ,K 2 SO 4 ) (NaCl, KCl) Laboratory Tests Picture 5: Refractory failure due to heavy chemical attack Picture 6: Cup test to check infiltration of chemicals in the refractory mature failure of refractories (Picture 5), which in turn leads to unplanned breakdowns/ shutdowns of cement plants. NaCl, KCl, Na 2 CO 3 , K 2 CO 3 ) are kept inside the cup and heated to 11000 C. This temperature is held for 5 hours. After cooling the sample, the cup is cut into two parts and chemical reaction and infiltration can be seen on the surface of the refractory (Picture 6).