Life Cycle Assessment (LCA) of Mining Waste Facility (MWF) Operations

Abstract

Historical tailings, once considered waste due to technological limitations, are now increasingly recognised as potential secondary sources of valuable materials. This study applies an ex-ante and prospective Life Cycle Assessment (LCA) to evaluate the environmental impacts of reprocessing historical iron tailings in central Sweden, under current technologies and projected future scenarios. The tailings are characterised by a high content of apatite, along with iron (Fe) and rare earth elements (REEs) such as monazite, presenting opportunities for recovery as secondary resources. Given that apatite is the primary mineral source of phosphorus in the form of P2O5, a critical nutrient for agriculture and food production, this study focuses on apatite recovery. The results show that reprocessing using current technology yields environmental benefits in several impact categories, including ecotoxicity (freshwater and marine), human toxicity (non-carcinogenic), and material resource use, as assessed by the ReCiPe 2016 method. However, the process also introduces environmental burdens, particularly in the categories of climate change, land use, and water use. Transitioning to fully renewable electricity significantly reduces these burdens and could lead to fossil-free energy demand. This comprehensive assessment of the environmental implications of tailings reprocessing provides valuable insights to support circular economy strategies to extend material life cycles by reusing mining residues.