An Overall Furnace Model for the Silicomanganese Process

Manuel Sparta,Vetle Kjær Risinggård,Svenn Anton Halvorsen,Kristian Etienne Einarsrud

doi:10.1007/s11837-021-04791-y

Manuel Sparta, Vetle Kjær Risinggård + Show 2 more

Open Access

https://doi.org/10.1007/s11837-021-04791-y

Copy DOI

Abstract

Controlling and optimizing smelting processes in submerged-arc furnaces are complicated by the limited amount of information available regarding the internal conditions. Computer models can help to bridge this knowledge gap. Due to the process complexity, computer models are commonly restricted to electrical conditions, thermal conditions, or chemical reactions, for instance. We have developed an overall model for a pilot-scale silicomanganese furnace that simultaneously considers electrical and thermal conditions, process chemistry, and flow of solid and liquid substances. To the best of our knowledge, this is the first comprehensive silicomanganese furnace model. The model has been compared to experimental data. Using information about the inner state of the furnace provided by the model, we are able to predict and explain an increase in temperature during over-coking as well as changes in the product compositions.

Highlights

Silicomanganese is produced by carbothermic reduction of manganese oxides and quartz in a submerged-arc furnace.[1,2] Pilot-scale experiments have been used to understand aspects of the electrical operation, process chemistry, effect of different raw materials, and effects of trace elements.[3,4,5,6,7,8,9,10,11] This article describes a comprehensive model for a pilot-scale silicomanganese furnace
We have developed an overall model for a pilot-scale silicomanganese furnace that simultaneously considers electrical and thermal conditions, process chemistry, and flow of solid and liquid substances
We have developed an overall model for a pilotscale silicomanganese furnace

Summary

INTRODUCTION

Silicomanganese is produced by carbothermic reduction of manganese oxides and quartz in a submerged-arc furnace.[1,2] Pilot-scale experiments have been used to understand aspects of the electrical operation, process chemistry, effect of different raw materials, and effects of trace elements.[3,4,5,6,7,8,9,10,11] This article describes a comprehensive model for a pilot-scale silicomanganese furnace. Q is the local medium density, cp is its specific heat capacity, k is its effective thermal conductivity, T is its temperature, vi are the velocity components of the granular flow, xi are the position coordinates, and Q is the local heat generation or consumption Both the density and the heat capacity depend on the charge and coke bed compositions with the same formalism as in Eq 8. Given the slag-to-alloy ratio for the simulated production, this charge corresponds to a slightly over-coked furnace, the slow increase in the size of the coke bed after about 2 h in the animation in the Supplementary Material.*. To metal requires the simultaneous presence of oxides as well as carbon, the increase of the coke bed and the resulting displacement of the oxides move the production of metal higher in the furnace This separates the endothermic alloy-producing reactions from the site of heat generation at the tip of the electrode. In a severe reduction of the coke bed and a corresponding reduction of the temperature of the lower part of the furnace

SUMMARY

Findings

CONFLICT OF INTEREST