PROCESS FOR THE PRODUCTION OF IRON FROM FINE-GRAINED IRON ORES

摘要

A process of producing iron from fine-grained iron ore by direct reduction, which includes adding oxygen, sponge iron and at least one of coal fines and low-temperature carbonized coal to an iron bath in a melt gasifier to produce a reducing gas, regulating the temperature of the reducing gas by blowing coal fines into it to produce a cooled reducing gas and a low-temperature carbonized coal, separating the low-temperature carbonized coal from the cooled reducing gas in order to use the separated low-temperature carbonized coal in the melt gasifier, preheating a fine-grained iron ore with a used reducing gas containing carbon monoxide to a temperature from 450 DEG to 700 DEG C., and reducing the preheated fine-grained iron ore with the cooled reducing gas at a temperature from 700 DEG to 1100 DEG C. in at least one fluidized bed to produce sponge iron and used reducing gas containing carbon monoxide, wherein the step of preheating the fine-grained iron ore results in decomposition of at least part of the carbon monoxide contained in the used reducing gas, producing a carbon layer on the preheated fine-grained iron ore, and also producing an exhaust gas and additional heat.