METHOD FOR REFORMING GRANULAR MATERIAL FROM IRON ORE POWDER UTILIZED FOR THERMAL CRACKING OF HEAVY GRAVITY OIL

PURPOSE:To provide large crushing strength to a titled granular material with a method for preheating said material in a grate kiln by heating the material to a prescribed temp. in a preheating temp. then passing air in a calcination chamber and heating up the granular material. CONSTITUTION:The carbon-stuck iron ore powder byproduced in the stage of producing light oil and cracked gas by thermal cracking of residual heavy gravity oil with iron ore powder as a heat medium are molded to a briquette shape. The briquettes are passed through a preheating stage and thereafter reduced iron is produced with the carbon thereof as a reducing agent. The briquettes 15 are continuously supplied into the traveling grate 18 of a grate kiln 14 consisting of a preheating chamber 16 and a calcination chamber 17 in succession thereto in the above-described preheating stage of the process for producing said granular material. Then, the briquettes 15 are heated to 600-700 deg.C by the high temp. gas from a hot stove or burner 20 in the chamber 16 while the briquettes are carried, then the carbon in the briquettes is allowed to burn of itself by the air from a fan 27 in the chamber 17 to attain 1,000-1,300 deg.C by which the briquettes are calcined.