• Low metal grades and the enormous volumes of mineral waste materials do not allow for traditional metallurgical processes to process the material and recover metals. Low-cost and low-intensity technologies that can process large volumes of material are urgently needed for wastes.
  • Whilst in situ metal leaching approaches such as heap leaching have been developed and utilised for metal recovery from primary low-grade Cu, Au and U ores the application of heap leaching technology to much more complex mineral waste materials is new and constitutes a promising research gap to be explored.
  • The development of the heap leach technology for waste is a question of research and development of appropriate (environmentally benign and effective) lixiviants which can be used in conjunction with low-intensity metal capture systems
  • In 2016, VITO was one of the first research institutes to report experimental research regarding heap leaching of mineral waste using lab scale column leaching tests that provide information on the leachability of metals from the material and permeability of leaching liquors through the material. As yet corresponding low-intensity metal capture systems have not been developed.