Long-term Consolidation of Two New Polymer Treatments of Oil Sands Fluid Fine Tailings

ABSTRACT: This paper examines the effects of two new polymers (cationic and neutral) on the consolidation behaviour of FFT compared to A3338 polymer treatment. Seven large strain consolidation experiments were completed, two for each polymer type and one control sample of untreated FFT. Furthermore, the material properties of untreated and treated FFT were analyzed. Results indicate that at the end of self-weight consolidation, a demonstrably higher dewatering efficiency of the neutral polymer on FFT was observed relative to the cationic and anionic polymers determined by the change in void ratio of each treated specimen. At each load step, the hydraulic conductivity and compressibility of FFT treated using the neutral and cationic polymers were higher compared to the anionic polymer and control sample. Moreover, at a given solids content, the shear strength of the new polymer treatments was an order of magnitude higher than the anionic polymer. Below a solids content of 35 %, the neutral polymer produced about twice the shear strength of FFT treated with the cationic polymer, which is attributed to the distinct structure the neutral polymer creates following treatment.