Coke Gasification in Blast Furnace Shaft Conditions with H2 and H2O Containing Atmospheres

Most of world steel in 2018 has been produced from virgin iron ore via the blast furnace (BF)-basic oxygen furnace route. Therewith the BF is one of the most important unit processes in worldwide steel making. Among others, energy efficiency of the BF is dependent on coke reactivity. Coke gasification occurs via solution-loss reactions either with CO2 or H2O. Herein, the gasification of coke is studied in CO-CO2-H-2-H2O-N-2 atmosphere simulating the BF conditions. The simulated atmospheres are based on the measurements from an actual BF. This research studies the effect of the composition of the BF atmosphere representing conditions near the wall as well as at the center and influence of the H2O content on coke gasification under simulated BF conditions. It is found that the location plays a role in coke gasification: wall atmosphere yields higher coke gasification compared with center. Dynamic tests show that introduction of H-2 and H2O in gas atmosphere fastens coke gasification by +119% at temperature range between 800 and 1200 degrees C in wall conditions. When H2O is present in gas atmosphere, the mass loss of coke is also greater in both wall and center conditions.

Automated summary

This study investigates the impact of BF atmosphere composition on coke gasification, finding that coke gasification is faster in wall atmosphere conditions, and the introduction of H2 and H2O can accelerate coke gasification.