Slag optimisation considering iron loss and sulphide capacity in hot metal desulphurisation

Conference paper (2018)

Authors

F.N.H. Schrama (OLD) MSE-3 , Tata Steel Europe Limited
Elmira Moosavi-Khoonsari Tata Steel Europe Limited
Elisabeth M. Beunder Tata Steel Europe Limited
Chris Kooij Tata Steel Europe Limited
R. Boom (OLD) MSE-1
J. Sietsma (OLD) MSE-3
Y. Yang (OLD) MSE-3
Research Group
(OLD) MSE-3
Slag Hot Metal Desulphurisation Iron Loss Slag Skimming Sulphide Capacity
More Info
expand_more

Published Date

2018

Language

English

Reuse Rights

Other than for strictly personal use, it is not permitted to download, forward or distribute the text or part of it, without the consent of the author(s) and/or copyright holder(s), unless the work is under an open content license such as Creative Commons.

Research Group

(OLD) MSE-3

Abstract

The slag in the hot metal desulphurisation (HMD) process should have a high sulphide capacity to capture the sulphur and a low viscosity to minimise the iron loss; in particular the emulsion loss. Although the slag composition changes during the HMD process as a result of reagent injection, the initial slag from the blast furnace (BF) is still the main constituent of the slag after HMD. Therefore, an average composition of BF slag is used as a starting point in this study. Using FactSage 7.1 thermochemical software, the influence of slag composition and temperature on the sulphide capacity is calculated. The slag basicity (CaO/(Al2O3+SiO2)) has the strongest influence on the sulphide capacity. Furthermore, the influence of CaO and temperature on the liquid viscosity and solid fraction of the slag is calculated and compared with plant data from Tata Steel, The Netherlands. Although the addition of CaO decreases the viscosity of the liquid part of the slag, neglecting the solid particles, it strongly increases the solid fraction of the slag. Based on the Einstein-Roscoe theory, more CaO leads to a higher slag viscosity and consequently a higher iron loss.