PROJECT DESCRIPTION
BACKGROUND
About 4.8 million tonnes of white slag waste material are produced every year by Europe’s 300 steel plants. This is a special waste that mostly requires landfill disposal since no real widespread technology has been adopted to treat it. However, so called ‘SNOW technology’ offers new opportunities to reuse free lime components of white slag as an additive for steel production. Free lime (CaO) makes up approximately 40-45% of the white slag material and reuse of this would reduce pressures on natural limestone resources (as well as reduce the considerable energy inputs and emissions involved in converting calcareous rocks into limestone). On a European level it is estimated that more than two million tonnes of lime could be recovered from white slag, thus saving 3.6 million tonnes of natural resources from calcareous quarries.
OBJECTIVES
The SNOW-LIFE project’s main goals focused on demonstrating the potential of SNOW technology to act as a cost-effective waste reduction and reuse solution for white slag (and associated frazzled refractory linings) from EU steel plants. An innovative system would be tested to verify optimal operational parameters for recovering free lime, dololime and magnesium oxide from white slag and exhausted refractory materials. The recovery process aimed to include reintroducing the materials directly back into the same steelmaking process, thereby substituting 30-50% of the lime additive presently purchased.
In particular, the project activities aimed to: minimise electric arc furnace slag (EAF) waste; limit the negative environmental impact of slag waste and its’ disposal in landfills; reduce demands on natural resources; decrease greenhouse gas emissions; and clarify solutions to help SNOW technology to be replicated as part of a zero-slag waste steel production cycle throughout EU steel making plants.
RESULTS
The SNOW-LIFE project has been terminated at an early stage, due to the impossibility of obtaining the needed authorisation for installing the pilot plant. None of the set milestones were therefore achieved.
