Steel industry co-products such as blast furnace slag are very often recovered and used as a raw material. For example, this is often the case where blast furnace slag is used in the construction sector, replacing the need for clinker.

The steel industry has developed a methodology to calculate the life cycle inventory (LCI) for the slags from the steelmaking processes. It can also be used in LCA studies where the worldsteel approach to dealing with the industry co-products of system expansion is not in line with the relevant standards being used. This methodology is not the position of the World Steel Association or EUROFER. It has been developed based on the EUROFER IPP Project final report that was published in 2007 and is available on the EUROFER website. Part of the EUROFER IPP project included developing a method for how to calculate the LCI for slags produced in the steelmaking processes. This method has since been further developed by the steel industry in order to provide a methodology to determine the LCI for steel slags and is also available to be used when system expansion (the current worldsteel approach to dealing with multi-functional systems) is not possible. This methodology is not mandatory but has been reviewed to be in line with the ISO 14044: 2006 and EN 15804 standards. The worldsteel methodology remains as outlined in the worldsteel methodology report, 2011.

For more information contact Clare Broadbent,

Methodology for slag LCI calculation