In WP1, 3 ESRS develop methodologies to assess the resource potential of Europe’s main sulphidic tailings families. More specifically, ESR1 develops and performs a tailored resource potential methodology for the Cu-Zn tailings from the Neves-Corvo Volcanogenic Massive Sulphide (VMS) ore deposit (Portugal); ESR2 performs an advanced geochemical and geometallurgical study with respect to the tailings of an epigenetic, Mississippi Valley-type (MVT) Zn-Pb deposit in Belgium. ESR3 addresses the tailings of a closed Cu-Zn-Pb mine in the Freiberg region in Germany. ESR3 applies the PERC standard requirements to establish the economic potential of these tailings and constructs, amongst others, a 3-D resource potential model.
WP2 explores the synthesis of novel mining chemicals and advanced processes for metal-extraction and metal recovery from tailings. ESR4 develops novel, selective, bio-based mining chemicals for the froth flotation of Cu-Zn, Zn-Pb and Cu-Zn-Pb tailings. These mining chemicals are based on lignocellulosic materials; Concurrently, ESR5 focuses on the development of ion-flotation chemicals that can be used in the metal-recovery step of the tailings reprocessing chain; ESR6 investigates the basics of selective flocculation for sulfidic ores to allow for a radically improved flotation process; ESR7 investigates the use of microwaves (MW) to increase the selectivity, efficiency and kinetics of and solvometallurgical leaching systems for tailings; Concurrently, ESR8 aims at a new leaching approach using salt-containing water sources, such as sea water, in order to save scarce resources; ESR9 develops a bioleaching approach to extract both valuable and hazardous elements (As,Cd) from Cu-Zn, Zn-Pb and Cu-Zn-Pb tailings. The novelty is that ESR9 targets the use of (halo)alkaliphilic sulphur oxidising micro-organisms that live in neutral to alkaline conditions. These are then used to treat tailings in neutral to alkaline conditions; ESR10 develops an innovative process for the recovery of metal ions from acidic sulphate solutions (as generated by the metal extraction step in SULTAN) by ion flotation.
In WP3, three parallel routes are investigated to valorise the mineral fraction of the SULTAN tailings, which represents more than 90 wt% of the initial mining residue material. ESR11 studies pre-treatment methods to increase the alkali solubility of Al, Si, Fe and Mg from the SULTAN tailings in the synthesis of inorganic polymers from purified mineral residues, targeting sound mechanical properties. In parallel, ESR12 investigates the possibility to blend cleaned tailing residues into the production of ceramics, ranging from roof tiles, blocks to pavers. ESR13 is developing new cement chemistries to develop flowable tailing-based cements for underground applications.
WP4 deals with the environmental assessment of the developed value chains. Considering the presence of low concentrations of hazardous elements (e.g. As, Cd) in sulfidic tailings, ESR14 studies the environmental and health impact of these elements in the processing chain from untreated tailing to final downstream product. Finally, ESR15 performs a Life Cycle Assessment (LCA) of the complete system, collaborating with all other ESRs. The new valorisation processes are benchmarked and compared among each other as well as with the environmental impacts of conventional tailings processing.
