Technology of gold recovery from gold-bearing technogenic raw materials

The increasing tendency to larger volumes of man-caused mineral resources to be processed with a view to recover gold at low operating costs demands innovations development. Gravity concentration methods, permitting to reduce metal and power consumption, as well as adverse environmental impact, and also providing for a high degree of concentration, comply with the necessary requirements. The subject of research was aged dump tailings of the gold recovery plant with a gravity-flotation processing flow sheet. As a result of the research, aged dump tailings material composition was studied and a gravity gold recovery flow sheet was proposed. Different analytical methods and apparatuses were used in the material composition studies: mineralography and electron-microscopic analysis (Axioscope 40 A pol, ZEISS, Germany), scanning electron microscope Hitachi TM 3000 (Japan); X-ray fluorescence analysis (x-ray wavelength-fluorescence spectrometer Shimadzu XRF–1800); atomic emission spectral analysis (atomic emission spectrometer «Stream»); fire assay test and fire assay atomic-and-absorption analysis (HCAM 497-XC methodology). Gold occurrence forms and its character of associations with ore components, base metals’ grades, gold distribution in size fractions, fineness of gold, ore and gangue minerals were determined. In-process testings were performed on centrifugal separators Falcon, Itomak, Kelsey, SKO and Gemeni concentrating tables. It is shown, that the environmentally friendly processing flow sheet permits to recover more than 31 % of metal into concentrate with gold grade of ~30.5 g/t.