Investigation on the possible concentration of oxidized gold ores in the knelson concentrator

In this study, the concentration possibilities of an oxidized gold ore with an Au content of 4.57 g/t using a Knelson separator (MD3 laboratory scale) were investigated. In this context, it is aimed to determine the most suitable operational conditions by using statistical experimental design methods. The study parameters whose effects were examined within the scope of the study were G force, wash water, feed rate, and solids ratio. Evaluation of the experimental studies was carried out statistically using the gold grade and recovery of the concentrates obtained. With the help of statistical data, models revealing the effects of G force, wash water, feed rate, and solids ratio parameters on gold grade and recovery were established. In addition, the effects of the parameters and their interactions were discussed based on ANOVA and response surface graphs. As a result of the experiments, when grade was prioritized, a concentrate containing 44,4 g/t Au was obtained with a 70,8% recovery at 60 G force, 250 rpm feed rate, 3 l/min wash water rate, and 40% solids ratio. In the case where the recovery was prioritized, a concentrate containing 33,9 g/t Au was obtained with a 76,8% recovery at 100 G force, 250 rpm feed rate, 2 l/min wash water rate, and a 20% solids ratio. As a result of the ANOVA analyzes performed on the experimental results, models were established for grade and recovery. The model established in the case of grade was statistically significant, with an R2 value of 0,8762. The model established for recovery was also statistically significant with an R2 value of 0,8685. Grade and recovery values estimated by these models were found to be in high agreement with the experimental data. The relations of the parameters with grade and recovery and their interactions with each other were discussed as well. In addition, bottle roll tests were conducted on fresh ore and KC tailings obtained under determined conditions. As a result of bottle roll tests, it was found that gravity concentration prior to leaching lowered both retention time and cyanide consumption from 48 hours to 10 hours and 0,76 kg/mt to 0,50 kg/mt, respectively.