One of the main tasks within the LIFE 5REFRACT project is to quantify the environmental benefits associated to the new strategies for refractory waste management devised and implemented as part of the project. As leaders of this task, 2.-0 LCA consultants set out to determine, as a first step, what is the current situation or baseline for this type of waste in the Basauri steel works, in order to use this as a benchmark against which to assess improvements.
For this purpose, a life cycle assessment (LCA) study has been conducted, where the unit of analysis is the management of the total amount of refractory waste generated at the steel works in 2018. Primary data were collected to quantitatively describe such aspects as the amounts and composition of waste produced in that period, the collection and transport procedures in the steel works, the type of treatment received by each waste fraction (reuse, recycling, landfill) and where does this treatment take place, among others. Given that a substantial part of these refractory materials is already today being reused or sent for recycling, the implications in the corresponding supply chains were included in the study, such as the induced reduction in mineral extraction and processing – typically taking place in China – transport of these raw materials to Europe, manufacture of finished products, etc.
The result of this baseline assessment is that the current management of refractory waste at the Basauri plant leads to a net environmental benefit, when compared to a situation where all materials were simply landfilled. This is due to the fact that the environmental impact of collecting, transporting and treating this waste is lower than that of producing new refractory raw materials and products (see Figure 1). This environmental benefit amounts to an annual saving of approximately 3,000 tonne CO2-equivalents, 28,000 m3 freshwater and 16 Terajoule primary energy from fossil sources. To put this in context, a power plant consuming this amount of primary energy as fuel, would be able to supply the entire city of Barcelona for around 5 hours.
Figure 1. Life-cycle greenhouse-gas emissions for management of refractory waste generated in the Basauri steel works in 2018. Negative figures are interpreted as avoided emissions. The net environmental benefit of current management, compared to a landfill scenario, is a saving of 3,032 + 45 = 3,077 tonne CO2-eq.