International Scientific Journals
of Scientific Technical Union of Mechanical Engineering "Industry 4.0"

A sample of acid drainage waters generated after rainfall in a dump of low-grade copper ores and mining wastes was tested under laboratory conditions to combine the treatment of such waters with the subsequent generation of electricity. This combination was possible and efficient due to the fact that the same microorganisms participated in both processes, i.e. in the water treatment and in the electricity generation. These microorganisms were heterotrophs related to two main groups: of sulphate-reducing and iron-reducing bacteria. These bacteria were anaerobes, with efficient growth and activity at pH within 3.0 – 3.5 using the organic donors of energy and avoiding the precipitation of the trivalent iron