Together with RAUCH Furnace Technology GmbH, the ACR Institute ÖGI has laid the foundation for more environmentally friendly magnesium production with its developments for optimising the inert gas supply and is being awarded the ACR Innovation Award 2023 for this.
With its good material properties and low mass, magnesium is proving to be a versatile and sought-after material. However, its extraction and processing is associated with high energy consumption and greenhouse gas emissions. The recycling of magnesium scrap therefore holds great potential for savings, but requires precise and reliable process control. After all, liquid magnesium burns on contact with air, which makes it necessary to use inert gases in processing. If contaminated magnesium scrap is used, this not only affects the melting process and the material quality, but also the process reliability. In order to minimise the tendency to burn and to avoid serious accidents, a precise, controlled supply of protective gas is necessary.
Due to their environmentally harmful effect, many shielding gases used in the past may no longer be used today. As an alternative, foundries are therefore increasingly relying on sulphur dioxide (SO2). But this only solves part of the problem. For one thing, the formulation of the gas mixture is currently purely empirical, whereby an incorrect composition can result in dangerous reactions. Secondly, the mixtures are usually only used once, which runs counter to the circular economy called for by all sides.
The central intention of the "SMgC" project was therefore to establish a control loop for protective gas mixtures in magnesium processing. "With our research and development strategy, we are pursuing the goal of increasing sustainability in the magnesium foundry," says Florian Sipek, Head of R&D at RAUCH Furnace Technology.
In close cooperation, the project partners succeeded in a first step in making the relevant process variables measurable by means of a specially developed analysis method. The influence of individual parameters on the process and the end product was then tested in a research test furnace under real conditions. The development, technical implementation and process-related verification of a control loop for protective gas mixtures for magnesium melts is a significant milestone for the entire industry. The new type of analytics makes it possible to optimise the composition and consumption of the inert gases used. At the same time, the project partners were able to create the necessary basis for using shielding gases more efficiently in the future with a recycling plant. Only a fraction of the active components are actually consumed in the furnace passage.
"The main result of the research project is that it is possible to increase the safety of the process and greatly reduce emissions into the environment, which also means financial savings for companies," emphasises Peter Liepert, project manager at ÖGI. The entire metal-processing industry and above all SMEs benefit from this. Since the demand for magnesium is increasing worldwide, but at the same time the requirements for the recyclability of products are also increasing, the analytics developed are paving the way for a sustainable and future-oriented foundry industry.
Visit RAUCH Furnace Technology GmbH at EUROGUSS 2024 at Hall 9 / Booth 9-617
