Biomining: an Established and Dynamic Biotechnology

Abstract

“Biomining” is generic term to describe the application of living organisms to extract and recover metals from mineral ores and waste materials. Since its inception as a crude technology (“dump leaching”) for treating “run of mine” rocks and boulders that contained too little copper to be processed by conventional processing, engineering options used  in biomining have become  increasingly  refined and diverse. Currently, microbiological processing is used to extract both base metals (copper, and to lesser extents nickel and zinc) and precious metals (mostly gold) from ores and mineral concentrates in heaps and stirred-tank bioreactors, as well as in dumps. Recent developments  include  the demonstration, at pilot-scale, of  indrect  leaching of zinc  sulfide concentrates,  in which the biological step (regeneration of ferric iron) is carried out independently of abiotic mineral oxidation, and  using microbiologically-mediated  reductive  dissolution  of  ferric  iron minerals  to  liberate  nickel  from lateritic ores.