2011 Volume 97 Issue 12 Pages 597-603
In order to further reduce CO2 emission in ironmaking, influence of half substitute of hydrogen to bosh gas on reaction behavior of sinter under several blast furnace simulated conditions with different thermal reserve zone temperatures (TRZ temp.) was examined until 1400°C under load by a laboratory reactor.
In case of TRZ temp. 1000°C, reduction of sinter finalized around 1100°C in the condition of H2 substitute, while the reduction retarded around these temperatures in the condition without H2 substitute. In case of TRZ temp. 800°C, the reduction progressed slower than the former cases as a whole.
The condition of H2 substitute provided higher carbon contents in sinter after reduction than the condition without H2 substitute. Moreover, the substitute improved the softening melting behavior of sinter by nearly 100°C.
Analysis by List model indicated that H2 substitute gave less coke rate and less BF productivity, whereas lowering TRZ temp. gave less coke rate and larger BF productivity compared with a basic operation.
The model analysis also evaluated that less BF productivity with H2 substitute could be improved by making the blast condition higher temperature or oxygen enriched.