A Statistical Model for Slurry Thickening

Thickening is the first step in the design of sustainable (cost effective, environmentally friendly, and socially viable) tailings management solutions for surface deposition, mine backfilling, and sub-aqueous discharge. The high water content slurries are converted to materials with superior dewatering properties by adding long-chain synthetic polymers. Given the solid and liquid composition of a slurry, a high settling rate alongside a high solids content can be achieved by optimizing the various polymers parameters: ionic type (T), charge density (C), molecular weight (M), and dosage (D). This paper developed a statistical model to predict field performance of a selected metal mine slurry using laboratory test data. Results of sedimentationconsolidation tests were fitted using the method of least squares. A newly devised polymer characteristic coefficient (Cp) that combined the various polymer parameters correlated well with the observed dewatering behavior as the R equalled 0.95 for void ratio and 0.84 for hydraulic conductivity. The various combinations of polymer parameters resulted in variable slurry performance during sedimentation and were found to converge during consolidation. Further, the void ratio-effective stress and the hydraulic conductivity-void ratio relationships were found to be e = a σ′ b and k = 10 (c + e , respectively.