Materiały konferencyjne SEP 2025

2 increasing. particularly for neodymium-iron-boron magnets—the strongest known type. Additionally nickel-metal hydride batteries rely on lanthanum-based alloys for their anodes [2,3]. Due to their importance for the economy Heavy rare earth elements (HREE) as well as Light rare earth elements (LREE) have been recognized as critical raw materials by the European Commission and have been placed on the Fifth list 2023 of critical raw materials for the EU [4]. Although primary deposits containing monazite. bastnaesite. and xenotime are the main sources of REEs. these elements can also be recovered from secondary sources such as mine residues and industrial waste [5]. This paper presents selected potential secondary sources of rare earth elements located in Europe. These sources were identified and investigated within the framework of the International ENVIREE project (ENVIronmentally friendly and efficient methods for extraction of Rare Earth Elements from secondary sources) conducted in 2015 – 2018, funded by the ERA-MIN program. The project aimed at developing novel methods for the recovery of rare earth elements from secondary sources. 2. CHARACTERIZATION OF SECONDARY SOURCES OF RARE EARTH ELEMENTS FROM THE MINING SECTOR 2.1. Selected mining sites In Europe, several landfills and tailings ponds containing post-mining waste have the potential to serve as sources of rare earth metals. As part of the project, waste materials from Sweden, Portugal, Slovakia, the Czech Republic, Poland, and Cyprus were selected for preliminary analysis. Four priority REE sources were identified: Covas (Portugal), Cumieira (Portugal), New Kankberg (Sweden), and KGHM (Poland). In addition. it was decided to conduct analyses for 4 other sources: Staszic mine in Rudki (Poland), Rožná mine (Czech Republic), Ervideira – (Portugal), Regtepoort (South Africa). Covas (Portugal) Mining waste in Covas originates from tungsten extraction (1954–1984). The deposit contains sulfides (pyrrhotite. pyrite. arsenopyrite. chalcopyrite) with wolframite. scheelite. and ferberite. The mined material was processed via electromagnetic separation. sintering. and flotation. The waste dump was closed and rehabilitated. Total waste volume was estimated 300.000 m³ . Cumieira (Portugal) The deposit consists of shales. quartz. granite. and aplite-pegmatite. Initially. the area was exploited for tin (Sn) (cassiterite). and later for niobium-tantalum (Nb-Ta) (coltan). Mining activities took place from 1927 to 1966.Initially mined for tin (Sn) and later niobium-tantalum (Nb-Ta). operations ran from 1927–1966. The ore was processed mainly through hydrogravity methods and electrostatic separation. the total REE content in the tailings may reach 394ppm. New Kankberg (Sweden) Gold and tellurium extraction at this site began in 2012. with an annual capacity of 400.000– 500.000 tons. The gold content is about 4 g/t of material. Ore is extracted from an underground mine and transported to a nearby processing plant in Boliden. The processing includes crushing. grinding. flotation. and cyanide leaching. The residues from these processes are directed to tailing ponds The mine was expected to close in 2023. Flotation tests indicated that most of the REEs occur in monazite. The total REO content in the sample was 2.916 ppm. with