The LIFE Green Casting project consortium presents the main conclusions obtained from the first industrial experiences of implementing inorganic binders in the manufacture of foundry molds and cores.
After having carried out the first tests at laboratory scale and in industrial environments, the LIFE Green Casting project consortium already has performed their first experiences implementing inorganic binders in industrial manufacturing processes of iron components.
Among the main conclusions obtained by the team after these first experiences, they have highlighted the good fluidity and compactation of these binders, as well as the good surface finish of molds and cores.
As explained by the AZTERLAN Sustainability and Environment researcher Erika Garitaonandia, “the results of the emissions tests during the casting process have also revealed significant advantages of inorganic binders compared to organic binders (phenol and furan based ones) and green molding”. In this area, the team has been able to observe a significant reduction in flame and gas emissions, with a decrease in BTEX (benzene, toluene, ethylbenzene and xylenes) emissions of 65-71% compared to green sand and higher than 90% compared to organic resins. In most systems, benzene was identified as the main component of these emissions. Organic binders showed higher emissions of particulate matter, NOx and SO2, while green molding recorded higher CO emissions. “This evidences not only that the use of inorganic binders optimizes the production process, but also contributes to creating safer and healthier working environments in foundries.”
However, foundries have also experienced technical challenges associated with the incorporation of inorganic binders. “Each foundry, due to their unique process and/or product characteristics, has had to face particular technical challenges. Although the sand preparation process is similar to that of traditional binders, we cannot ignore the fact that the transition to inorganic binders is not a simple and direct process, but rather requires specific adjustments in the production processes and, in some cases, modifications in the equipment used are necessary.” In this sense, the hardness of the cores after pouring process and their collapsibility during demolding have been the main focuses of work for the team. But the solutions developed have been very specific to each case.
Experiences of implementing inorganic binders in the Peiron and Valumehaanika foundries
After completing the first half of the project, the LIFE Green Casting project team continues to work on the safe incorporation of inorganic binders in the manufacturing of iron castings to determine successful references and best practices. “We continue to accompany the foundries and learn by their side during this transformation process that, little by little, will be inevitable for the sector.”
