ORE-POWDER CAKING MATERIAL FOR ENHANCING HOT STRENGTH, PELLET MADE WITH THE SAME, AND PROCESS FOR PRODUCING THE SAME

摘要

An ore-powder caking material which is for use in enhancing hot strength in pelletizing an ore powder. It is equal or superior in cold strength to conventional caking materials and is excellent in the impartation of hot strength. Also provided are a pellet made with the caking material and a process for producing the pellet. The ore-powder caking material for enhancing hot strength comprises either or both of cement and lime, slag, and a siliceous substance and has a chemical composition comprising CaO, Al2O3, and SiO2, wherein the contents of CaO, Al2O3, and SiO2 are 3-56%, 3-40%, and 30-86%, respectively, based on the sum of these. The caking material may be one in which the proportion of the either or both of cement and lime is 1-76 parts, that of the slag is 2-95 parts, and that of the siliceous substance is 2-95 parts. The caking material may be one which further includes gypsum. The pellet comprises an ore powder, the caking material, and water. The pellet may be one in which the amount of the caking material is 3-20 parts per 100 parts of the ore powder, and the water/(ore powder + the caking material) ratio is 0.03-0.3.