Material efficiency in iron making can be measured by following how much primary raw materials as iron ore and fluxes are needed for a ton hot metal production as well as how much primary reducing agents (coke and oil) are substituted by secondary reducing agents.
Material efficiency of iron making was improved by the project dramatically. Due to high recycling rate of iron bearing materials, carbon bearing residues and calcium containing slag residues virgin raw material usage could be decreased. In the later half year on 2013 was achieved the level which saves yearly:
- 185 000 tons of primary iron ore pellets (primary raw material degree from 94% to 88%)
- 40 000 tons of primary limestone (decreases also carbon dioxide emissions, bound in saved limestone)
- 42 000 tons of primary coke (secondary reducing agent rate 2,5% -> 6,5%)
The project includes research results from several competence fields as numerical and physical modelling, metallurgical experiments and industrial development and trials.
Material efficiency in iron making is a matter of cost efficiency and sustainability. Cost efficient production is a precondition for profitable steel production. In addition increased efficiency in iron making processes decreases carbon dioxide emissions and primary fossil fuel consumption leading to a more sustainability steel production. The decrease can be achieved via two ways:
- High efficient and optimized way to drive blast furnace process,
- Effective recycling of iron- and carbon-bearing materials as well as flux substituting materials
The achieved result saves raw materials creating costs advantages. In addition by the achieved increased material efficiency decreases arbon dioxide emissions and primary fossil fuel consumption leading to a more sustainability steel production.
Results have been able to be fully utilized in the real processes. The achieved results have been vital for business profit of Ruukki company.
Ruukki Metals Oy, Outotec, University of Oulu, Åbo Akademi