DIRECT REDUCTION OF IRON OXIDE IN FLUIDIZED BED OF COAL WITH RECYCLE OF FINE COAL PARTICLES TO FURNACE

摘要

A process and a plant for the direct reduction of iron oxide particles in a shaft furnace and for smelting the obtained iron sponge particles in a meltdown gasifier. A coal fluidized bed is formed in the meltdown gasifier by supplying coal and oxygen-containing gas, in which the heat necessary to smelt the iron sponge particles as well as the reducing gas to be injected into the shaft furnace are produced. The top gas remaining after the reduction is drawn off the upper part of the shaft furnace and the dusty solid particles, which are discharged together with the reducing gas and/or with the top gas, are washed out by scrubbers. The suspension of the washed out solid particles is thickened and separated into a clear overflow and a concentrated coal slurry. The coal slurry is recycled into the meltdown gasifier, is pressure-gasified with oxygen and is burnt by burners arranged in the upper part of the meltdown gasifier and directed towards the coal fluidized bed.