Life Cycle Assessment Comparison of Two Refractory Brick Product Systems for Ladle Lining in Secondary Steelmaking

Abstract

This paper aims to compare the environmental performance of two types of refractory bricks for the internal lining of ladles in secondary steelmaking, where the dissolved inclusions coming from the refractory material require fine control to obtain the target steel quality. In this context, magnesia-carbon-based refractories are largely utilized, thanks to the adequate durability of the ladle lining in terms of number of heats before re-lining, but the utilization of organic binders in the mixture (pitch, resins) arises ecological and human health concerns. Concurrently, research efforts in refractory material science look at improving the quality of steel by reducing the content of dissolved carbon due to the release from the bricks, thus focusing on different refractory materials and specifically on alumina-based materials. The European Commission funded the research project “LeanStory”, aiming to promote such new lines of refractories through the cooperation between industrial partners and scholars where different recipes are considered. In the present paper, two representative systems of the refractory types considered, magnesia-carbon and magnesia-alumina, are compared with a preliminary Life Cycle Assessment (LCA). Suppliers and transports for the two product systems have been taken into account, referring to one tonne of refractory material as the functional unit for comparison. Preliminary impact results (adopting the ReCiPe Midpoint–Hierarchist perspective methodology for calculating the impact indicators) show that the new solution performs largely better almost for each indicator. Further investigations are required in order to assess the ecological performance of the two systems, considering the effective consumption of bricks for the production of steel.