Green practices interest in foundry sector: A survey on the case of inorganic binders

Green practices serve as a mechanism to enhance Industry 4.0 from a sustainability perspective, particularly in sectors where environmental effect is significant. This issue is particularly significant for european ferrous foundries that face significant challenges due to increasing competition and tightening environmental laws. Despite technological innovations and legal requirements, they are still remarkable sources of pollution and hazardous emissions. Organic binders, a group of petroleum-derived resins, are widely used for manufacturing sand molds and cores - fundamental elements in the manufacturing process - but their use is problematic due to the release of toxic substances both during their use and the pouring of the metal. Inorganic binders, derived from sodium silicate and other geopolymers, represent a possible solution, thanks to the near-zero emission levels that they exhibit in both of these phases. These binders are nowadays commonly used in non-ferrous metal foundries, such as aluminium ones, but their use in ferrous foundries is limited due to the increased mechanical resistence that they present at high temperatures (characteristics of ferrous alloys) that make sand residues difficult to remove from the castings, and their storage time is limited due to their low resistance to humidity. Research and technical innovation have made improvements in these aspects, but the scalability of these solutions in iron and steel foundries remains unclear. This paper analyses responses to a questionnaire that 90 ferrous foundries from eight European countries answered. The aim of the survey was to understand the characteristics of the firms and their relationship with inorganic binders. In the conclusion, in addition to a summarisation of the data that emerged in the analysis, the possibilities that modern simulation and management tools offer to handle this transition are discussed, with a particular focus on the potential benefits arising from the possible use of simulation models.