Researches regarding elaboration of new technology for gold ore processing

The aim of the project was to promote performant technological solutions, efficient and more environmental friendly both in the sector of extraction/ore processing and in the field of process wastewater treatment. Treatment possibilities of wastewater from the recovering flows of precious metals based different solubilization systems (HCl + CaCl2, thiourea) were studied and it was elaborated the unitary treatment flow of wastewater from the processing of gold ore by solubilization/complexation with thiourea. Technical treatment flow of wastewater resulted from gold ore processing using thiourea, with high content of heavy metals and organic load, has the following phases: oxidation of organic load and oxidable heavy metals (Fe2+, Mn2+) with hydrogen peroxide (Fenton method), pH correction, metal hydroxides/oxides precipitation, flocculation of suspended matter, settling - phases separation. The treated wastewater is in agreement with discharging conditions into natural receiver to organic load and heavy metals indicators (Fe, Mn, Zn, Cd, Crt, Cu, Pb, Ni).