1991 年 77 巻 10 号 p. 1593-1600
A mathematical two-dimensional model is developed for analyzing inner circumstances of blast furnace at steady state operation. This model is consisted of a set of partial differential equations representing simultaneous processes of gas and burden flows, heat transfer and mass transfer with chemical rate processes. Derivation of governing equations, evaluation of transport parameters and a finite difference scheme for stable and effective computation of the large scale model are shown in this paper.
On the basis of a thermodynamic consideration of Si-O-C system, the mechanism of SiO formation in the dropping zone of blast furnace is considered to change from an equilibrium of SiO2-C to that of SiC-C at higher temperature where SiC becomes stable. The evolved gaseous SiO is kinetically reduced by dissolved and saturated carbon in hot metal.
The inner circumstances of a blast furnace with pulverized coal injection are numerically analyzed using the two-dimensional model, and the characteristics of distributed process variables are examined in comparison with those at all coke operation.