PURPOSE: To prevent the deterioration of sintered ore at the time of accumulating in the open air for storing by regulating the CaO content in the manufactured article of the sintered ore to the specific value or below.
CONSTITUTION: The compounding material for sintering in which the source of CaO is controlled in such a manner that the CaO content in the manufactured article of the sintered ore is regulated to ≤13wt.% is supplied into a sintering machine and is sintered. In the sintered ore obtd. by this method, the deterioration of strength can be prevented at the time of accumulating in the air for storing and the lowering of the yield can be prevented. At the time of >13wt.% CaO in the sintered ore, natural collapse takes place by the pouring into the water for two days, and its powder rate at the time of sieving the above sintered ore after the pouring is drastically increased as well.