Abstract
The vertical distribution of gas compositions, temperature, and pressure in the blast furnace stack, and also dust in shaft gas were investigated by the use of vertical probes. Furthermore, the water vapor content was determined by the dew point measurement.
Following results were obtained.
(1) Water gas shift reaction was in equilibrium in the temperature region higher than 800°C.
(2) The rate of indirect reduction of iron oxide showed a maximum between 1000 and 1050°C andthen decreased with formation of the shell of iron reduced.
(3) The rate of solution-loss reaction was controlled by the rate of indirect reduction of iron oxide in the temperature range higher than 900°C. The rate of solution-loss reaction RZS was expressed as follows. RZS (kg mol c/m3 bed. hr) =kS (PH2O+PCO2) ρc (%C/100) · (1/Mc)
kS (1/hr) =5.4×1011 exp (-67000/RT)
(4) Measured concentration of water vapor differed from that of calculated on the basis of mass-balance. The difference corresponded to the hydrogen content of heavy oil injected.
(5) Vapor pressure of potassium was estimated at 8.2×10-4 atm in the temperature range from 1000 to 1200°C and 3.7×10-4 in the range from 900 to 1000°C.
