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.

Original languageEnglish
Title of host publicationICS 2018 - 7th International Congress on Science and Technology of Steelmaking
Subtitle of host publicationThe Challenge of Industry 4.0
PublisherAssociazione Italiana di Metallurgia
ISBN (Electronic)9788898990146
Publication statusPublished - 2018
Event7th International Congress on Science and Technology of Steelmaking, ICS 2018 - Venice, Italy
Duration: 13 Jun 201815 Jun 2018


Conference7th International Congress on Science and Technology of Steelmaking, ICS 2018

    Research areas

  • Hot Metal Desulphurisation, Iron Loss, Slag, Slag Skimming, Sulphide Capacity

ID: 53580716