METHOD OF PRODUCTION OF SPONGE IRON IN SHAFT FURNACES Russian patent published in 2005 - IPC C21B13/02 

FIELD: ferrous metallurgy; production of sponge iron in shaft furnaces with the use of converted natural gas.

SUBSTANCE: proposed method includes reduction of descending iron ore materials in counter-flow with reducing gas at temperature of 800-1050°C at simultaneous recirculation and heating of process blast-furnace gas and catalytic reforming of natural gas in external return cycle with addition of oxidizing agent. Introduced into reformer as oxidizing agent is vapor-and-oxygen mixture at flow rate of up to 30 m³/t. Prior to mixing the vapor with oxygen, it is superheated to temperature not below 110°C; content of oxygen introduced into mixture does not exceed 40%. Blast-furnace gas is dehumidified before compression for obtaining required moisture content.

EFFECT: increased output of shaft furnace; reduced power requirements.

5 cl, 2 dwg, 2 tbl