The sticking problem during direct reduction of fine iron ore in the fluidized bed

Mirko Komatina,Heinrich W Gudenau

doi:10.30544/378

Abstract

In this review paper described are possible chemical reactions and their thermodynamic analysis during direct reduction. The sticking mechanism during direct reduction in the fluidized bed was analysed, and the reasons for the sticking appearance explained. The most important parameters on the sticking were analysed. The ways for prevention and observation were considered. The plan for experimental investigations was proposed. The investigations could be performed in fluidized bed reactor. Coal will be used as inert material. Separately, the influence volatile content in the coal on the reduction process and sticking appearance, will be analysed. As results of these investigations would be some improvements of the method direct reduction of iron ore in the fluidized bed.

Highlights

New processes for iron making were developed in the last few decades
The iron ore usually consists of hematite (Fe2O3) and / or magnetite (Fe3O4) and iron content ranges from 50% to 70%
Transformation of the iron ore into iron in the iron making process is performed through the following steps: from hematite (Fe2O3) it transforms to magnetite (Fe3O4), and later to wustite (FeO) and to iron (Fe)

Summary

INTRODUCTION

One of the new processes for iron making is direct reduction (DR). Transformation of the iron ore into iron in the iron making process is performed through the following steps: from hematite (Fe2O3) it transforms to magnetite (Fe3O4), and later to wustite (FeO) and to iron (Fe). - mass transport of gaseous reactants to the external surface of iron ore particle,. Hexagonal hematite lattice transforms into cubic magnetite lattice, volume increases, the firmness of the ferrit oxide crystals weak [1,2,3], and numerous cracks occur (Fig. 1.1, Fig. 1.2). During reduction the surface structure of wustite becomes more porous (Fig. 1.3). When hematite iron ore is reduced to iron, the surface is much more porous than the wustite structure (Fig. 1.4). In this paper the problem of sticking during direct reduction of fine iron ores in fluidized bed is considered

THERMODYNAMICS ANALYSIS

STICKING

THE IMPORTANT PARAMETERS

PREVENTION AND OBSERVATION

Findings

CONCLUSION