Material recycling of difficult waste materials from the foundry industry

 During three years (2022 - 2025) four companies in the Swedish metal and foundry industry (GreenIron, Sandvik, Scania and Österby Gjuteri) have joined forces with the research institutes Swerim and RISE to find alternatives to landfill, i.e. recycling and/or reuse, of some waste materials left over from casting processes. The materials in focus are scale from Sandvik, slags from Sandvik and Scania, grind and coolant mixture from Scania and dust from Österby Gjuteri. All the materials were considered as “difficult” to reuse or recycle at the beginning of the project.

The following tests have been performed within the project: • Reduction of metal oxides using GreenIron’s technology. Two tests were performed with the purpose to see how much of the metal oxides in the samples could be reduced to metal with aim to reuse it as raw material in production. Scales and dust showed most potential for reduction. • Separation of the metal fraction from slag to be able to reuse the metal fraction in production. • Get dust into pellets to make it possible to reduce by GreenIron’s technique, but also for a possible reclassification of the material to a non-hazardous material. Handling of non-hazardous materials are both safer and cheaper. • Separation of coolant from grind in a grind and coolant mixture. The coolant may be reused in production and the grind together with grinding chips can be pressed to pellets and then fed back as raw material to the production process.

The result of the project is that several of the ideas tested in the project are worth taking forward for further analysis and potential implementation. Five ideas have during the project been explored in overview business cases.

The work in work package 4 is part of the project HANS, which is a project financed by the Swedish Strategic Innovation Program Metallic Materials and a consortium of a total of 13 companies in the Swedish metal and foundry industry.