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

Abstract

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–H2–H2O–N2 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 H2 and H2O in gas atmosphere fastens coke gasification by +119% at temperature range between 800 and 1200 °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.

Metal Dusting Behaviour of Fe-Cr and Fe-Cr-Ni Alloys under Blast Furnace Operating Condition

“…Specimens were hung in a vertical tube reactor sitting inside a furnace for isothermal reactions at 550℃ and 650℃ in flowing gases for up to 100 h. The reaction gas composition was controlled by mass flow controllers to be Ar-33CO-7H2-7CO2-2H2O with a linear flow rate of 56 cm/min and 63 cm/min at 550℃ and 650℃, respectively. This gas composition was chosen based on the gas composition range in a blast furnace [12,13]. The wet gases were generated by passing a mixture gas of CO, H2, and CO2 through a water bath containing distilled water at a controlled temperature 29℃ [14].…”

Effects of Temperature and Additives on NOx Emission From Combustion of Fast-Growing Grass

“…11 (Liu et al, 2017;SchäferBonn, 2002) and Eq. 12 (Heikkilä et al, 2021;HermannHüttinger, 1986;MoulijnKapteijn, 1995); it also matters whether CO can convert NO to N 2 , whose reaction mechanism is shown in Eq. 13, 14 (Chan et al, 1983;Thomas et al, 1993;AarnaSuuberg, 1997;Dong et al, 2007;Gong et al, 2021).…”

Numerical Simulation of Combustion Characteristics in the Dome Zone of the COREX Melter-Gasifier: The Effect of Rising Gas

“…Therefore, its internal diffusion resistance is quite smaller compared with other types of gas compositions. 45 Once the excessive heat is consumed, it will cause the temperature drop of the dome, so the proportion of (CO + H 2 ) should be maintained at approximately 90%. 4.5.…”