绿色矿冶

The leachate of the residue from filtration of cyanidation tailings contains high concentration of total cyanide and can’t meet the requirement of relevant technical specification. Therefore, the NaHSO₃-air method is proposed for treating cyanidation tailings. In this paper, the optimal reaction conditions of the NaHSO₃-air method were studied based on test. The study showed that the best cyanide removal effect occurs under such conditions as NaHSO₃ dosage 6.00kg/t, initial pH value 9.5, CuSO₄·5H₂O dosage 300mg/L, no aeration, reaction lasting 2h and reaction temperature at 19℃. After 13 times of closed-circuit circulation under the optimal reaction conditions, the total cyanide in the toxic leachate was less than 5mg/L, meeting the cyanidation tailings treatment standard of TSF in the technical specification.