GB861477A - Method of making char-bonded pellets containing iron oxide and elemental iron, the pellets so produced, and the production of iron therefrom - Google Patents

Abstract

861,477. Reducing iron ores. JONES, L. E. (McWane Cast Iron Pipe Co.). May 2, 1957, No. 13981/57. Class 72 A process for the production of charbonded pellets comprises forming a moistened mixture of iron ore and carbonaceous fuel into green pellets, igniting the pellets and subjecting them to a blast containing 16% to 26% of oxygen, maintaining them at a temperature of 1600‹F. to 2300‹F. until the metallic iron content is between 15% and 40% of the total iron, and terminating the blast while more than 6.5% carbon is present. As shown, ore and coal are intimately mixed in a mixer 12 in the ratio of 60 parts ore to 40 parts coal with 10% to 20% of water and discharged to a pelleting drum 13 from which pellets are fed to a double screen 14a, 14b, the oversize from 14a being returned to the mixer feed, the undersize from 14b to the pelleting drum, and the oversize from 14b being delivered to a hopper 21 from which they are discharged on to a travelling grate 22 carrying them under an igniter 23 to a heating zone 24. An oxidizing blast is drawn through the heating zone by a fan 25 and the pellets are maintained at a temperature of 2000‹F. to 2300‹F. for a period of 8 to 12 minutes after which they are discharged on to a screen 26, the oversize passing to a hopper 29 from which it is discharged into a smelting furnace 30, the undersize being returned to the mixer. In a modification, Fig. 2 (not shown), the pellets are dried by heating before being ignited.