Abstract: A rotor was added to the experimental apparatus,making the apparatus more similar to an in-situ high-capacity thickener.With solid handling capacity per unit area and underflow volume concentration as two evaluating indicators of tailings thickening effect,the influence of some factors on tailings thickening effect was investigated using a uniform design method.It is shown that there is a positive correlation between the solid handling capacity per unit area and the flocculant's dosage,and the best feed volume concentration is 6.56%.The underflow volume concentration is of positive correlation with feed volume concentration,residence time and the flocculant's dosage,respectively.Through analyzing the settlement curve with a Cage settlement model,it is concluded that the speed limit layer is typically the separate layer of the transition region and the compression region.Based on experimental results and tailings handling capacity daily,the minimum diameter of a thickener is 14 m.