Abstract
To analyze reaction in a blast furnace shaft and other reducing furnaces, a reduction rate of an are bed must be calculated. Recently many mathematical models to describe a kinetics of iron are reduction have been proposed byEl-MEHAIRY, W. M. MCKEWAN, K. Motu, W.O. PHILBROOK and others.
The are bed was divided into several unit layers. The reduction of unit layer was divided into three steps, those were wustite, magnetite and hematite reductions. The mathematical model that was proposed by K. Mori with mixed controlling step by both chemical reaction and gas diffusion, was used for each reduction step.
The calculation for the first unit time was done step by step until reaching to desired heap. Then the calculation for the second unit time was done in the same way using the degree of reduction thet had been calculated at first unit time, and so on.
The calculated data was compared with the experimental data, and these data arrived at an essential agreement. The reduction by H2was controlled by interface reaction, but that by CO was controlled by both interface reaction and diffusion.
