MANUFACTURE OF LOW SIO2 SINTERED ORES OF HIGH QUALITY FOR IRON MANUFACTURING BY BLAST FURNACE

摘要

PURPOSE:To obtain sintered ores having same yield and quality or above to conventional ones by low SiO2 in the use of low SiO2 iron ores contg. Goethite by deciding the addition amt. of CaO to the material of the sintered ores with a specific index. CONSTITUTION:The powder of iron ores contg. Goethite in which =3.5% SiO2 is satisfied, sinter returns according to necessary, CaO-contg. auxiliary material powder and carbonaceous material powder are quarried. At this time, the CaO auxiliary material powder is controlled in such a manner that the compounding material except the sinter returns is regulated to 0.08=Rcao=0.25; where Rcao denotes [(CaO%-1.2XSiO2%)/(Fe%]. Water is ten added to the compounding material to mix, granulate and sinter by burning heat of coke breeze. By this method, with the use of porous low SiO2 iron ores contg. Goethite which has been a problem because of the lowering of the yield and quality of sintered ores, the sintered ores having the yield and quality equal to or above conventional ones can be obtd. with low SiO2.