The steel industry uses large amounts of carbon to reduce oxygen in the iron ore and convert ore into iron. Tests conducted where biogas replace the use of coal now shows promising results.
- A preliminary study showed that carbon dioxide emissions in iron can be reduced by one million tonnes, or 25 percent if the carbon is replaced with biogas made from logging residues, branches and tops, and /or stumps. A knock on effect is that an approximately equal amount of biomass must be harvested and transported to a user, says Professor Carl-Eric Grip, Luleå University, who leads the project BioDri.
The supply of biomass is thus central to if the cost of iron production with biogas to be kept down. In northern Sweden is currently a surplus of slash and stumps. But biomass cost much to ship to the manufacturing site.
In BioDri project Lulea researchers collaborate with LKAB, Energy Technology Centre in Piteå, ETC, Sveaskog, Billerud, Höganäs and MEFOS. Carl-Eric Grip and fellow researcher Andrea Toffolo investigates and builds models for how to generate the large amount of biomass required. Along with MEFOS the sientists developed models to optimize costs and environmental impacts of the entire chain from the harvesting of forest residues to finished iron.
Costs for example for transport of logging residues, adaptation of production equipment and facilities as well as transportation, energy consumption and carbon emissions, are factors that researchers experimenting with in the models. Gasification of forest residueis tested in ETC's pilot plant. Iron productionis tested by LKAB and Höganäs. The project BioDri is funded by the Swedish Energy Agency and participating partners.