Abstract:The research and application of synchronous gold recovery technology for treating cyanide-containing wastewater from gold mines by biological method was carried out. Through improving the anoxic-aerobic organism biological treatment process, the highly efficient degrading bacteria groups of CN- and SCN-, mainly Thiobacillus, Trupperia and Pseudomonas, were successfully domesticated and multiplied. In the industrial applications, the average removal rates of SCN-, COD, CN-, and NH3-N by biological methods are 99.98%, 97.63%, 86.74%, and 98.70%, respectively. The various pollutant indicators of the treated effluent are far lower than the first level standard of the Comprehensive Wastewater Discharge Standard (GB 8978—1996). Microorganisms, while degrading pollutants in wastewater, recover gold from mixed gold-containing wastewater with low initial concentration through their own oxidation, adsorption, flocculation and sedimentation. The gold recovery rate can reach 91% and the enriched gold levels ranging from 300 to 400 g/t, which not only deeply treat various pollutants in wastewater, but also recover valuable metals. It is an environmentally friendly and pollution-free treatment technology for cyanide-containing wastewater.