Abstract:Flocculating sedimentation is a critical step in the thickening and dewatering of tailings during the backfilling process in mines. A certain iron mine in Liaoning has a complex and diverse mineral composition, with a significant proportion of fine-grained tailings, which poses challenges such as slow sedimentation rates and high overflow turbidity for the flocculating sedimentation process. To study the flocculating performance and sedimentation mechanism of tailings from the iron mine, experiments were conducted using whole tailings as the main test material. Results of natural sedimentation and flocculating sedimentation tests were compared. Single-factor method was combined to carry out flocculant selection tests were conducted, with clarity of the supernatant and sedimentation rate being the main evaluation indicators. Ultimately, 655S flocculant with the best sedimentation effect was selected for subsequent flocculating sedimentation experiments. By adjusting flocculant unit consumption and filling slurry concentration, the effects of these two factors on the performance of slurry flocculation and sedimentation were analyzed separately. When feed concentration was below 20%, the optimal flocculant addition was controlled in the range of 15±5 g/t, with the underflow concentration reaching 62.61%. Findings of this study provided a theoretical basis for improving the quality and efficiency of fine tailings backfilling in similar mines, and had significant practical value and engineering guidance significance.