University of Oulu

Mikko Iljana, Antti Kemppainen, Timo Paananen, Olli Mattila, Erkki Pisilä, Mikhail Kondrakov, Timo Fabritius, Effect of adding limestone on the metallurgical properties of iron ore pellets, International Journal of Mineral Processing, Volume 141, 2015, Pages 34-43, ISSN 0301-7516,

Effect of adding limestone on the metallurgical properties of iron ore pellets

Saved in:
Author: Iljana, Mikko1; Kemppainen, Antti1; Paananen, Timo2;
Organizations: 1Process Metallurgy Group, University of Oulu, Finland
2SSAB Europe, Raahe, Finland
3Karelsky Okatysh, Severstal, Kostomuksha, Russia
Format: article
Version: accepted version
Access: open
Online Access: PDF Full Text (PDF, 0.7 MB)
Persistent link:
Language: English
Published: Elsevier, 2015
Publish Date: 2021-01-14


In order to produce high-quality pellets with good reducibility and superior softening and melting properties, certain additives are important. One of the most common fluxing materials for iron ore pellet production is limestone, which is mainly calcium oxide (CaO). In this study, the effect of adding limestone on the metallurgical properties (reducibility, swelling, cracking, softening temperature, Low-Temperature Disintegration, Cold Crushing Strength) of acid iron ore pellets was investigated using a comprehensive set of metallurgical laboratory tests.

The dynamic reducibility test under unconstrained conditions showed a higher final degree of reduction in limestone-fluxed pellets compared to non-fluxed ones. Also in the reduction–softening test under load, the fluxed pellets reduced to a higher final degree of reduction, although they started to soften at a somewhat lower temperature. Swelling and cracking of the pellets during dynamic reduction were slightly increased by the addition of limestone, but not remarkably. Adding limestone slightly decreased the Cold Crushing Strength and increased the formation of fines in the hematite to magnetite reduction stage in the LTD test. However, all four parameters (CCS, LTD, swelling, and cracking) are within the acceptable range for blast furnace use.

see all

Series: International journal of mineral processing
ISSN: 0301-7516
ISSN-E: 1879-3525
ISSN-L: 0301-7516
Volume: 141
Pages: 34 - 43
DOI: 10.1016/j.minpro.2015.06.004
Type of Publication: A1 Journal article – refereed
Field of Science: 216 Materials engineering
Funding: Ruukki Metals Oy (at present a part of SSAB) and the Finnish Funding Agency for Technology and Innovation (TEKES) are acknowledged for funding this work.
Copyright information: © 2015. This manuscript version is made available under the CC-BY-NC-ND 4.0 license