Epsilon Archive for Student Projects

Abstract

This thesis aims to investigate different treatment scenarios for the potential clean-up of Rönnskär’s historical copper slags and tailing sands. Both materials are known to contain potential toxic elements that can put the environment and humans at risk. Between 1930 and 1966, Rönnskär smelter had been using these by-products from enrichment and pyrometallurgical processing as land-fillings for the extension of its industrial area, located on an Island nearby Skellefteå (Sweden). The examined scenarios, namely Rönnskär, Boliden Area and Aitik, are all equipped with suitable technology but differ in their treatment methods as well as location along with required transportation. A social cost-benefit analysis is used to determine the net-present values of each scenario, based on economic, social and environmental input factors. All results state Boliden Area as the most beneficial scenario regarding the treatment of Rönnkär’s historical copper slags and tailings, showing only small deviations when purely focusing on environmental costs. Based on the remediation of 400 000t copper slags and tailings, this study’s calculations show a net present value of -772 kr/t copper slag and -530 kr/t tailings for Boliden Area. However, a total clean-up of the existing 5.5 Mton copper slag and
1.8 Mton tailings is currently impossible which is why further research and investigation is needed.