Influence of Zinc on Nonisothermal Gasification Kinetics of Coke in a Blast Furnace.

The effect of zinc on the kinetics of coke gasification was studied by a nonisothermal method. The results indicated that with the increase of zinc content, coke gasification tended to move to the low-temperature zone, it occurred earlier, and the reaction rate increased. The main curve fitting method was used to analyze the mechanism function of coke gasification before and after adding zinc. The modified shrinking core model was found to be the optimal mechanism function for coke gasification, with which the kinetic parameters obtained showed that the pre-exponential factor and apparent activation energy of coke gasification decreased significantly with the increase of zinc adsorption amount. Moreover, a kinetic compensation effect was found to exist in the effect of zinc on coke gasification. Combined with X-ray diffraction (XRD) and the peak fitting technique, it was found that the difference in the catalytic effect of zinc on coke gasification was attributed to the carbon structure.