Rheological Evaluation and Control of Flow Behavior of Concentrated Phosphate Mineral Slurries
The overall goal of this project is to find economic and environmental friendly ways to reduce energy consumption in pumping particulate suspensions such as phosphate concentrate sand tailings. Pumping sand tailings slurries at high solids content is desirable from technological as well as economical point of view. In this study, the fluidity of the samples was studied in the presence of surfactants, polymeric additives, and sodium silicate. A significant improvement in the fluidity and pumpability of sand tailing slurries was observed with the addition of surfactants (anionic and cationic) and polymers to the system. Sodium silicate did not significantly affect the fluidity of sand tailing slurries due to the large size of the particles. It appears that increase in the level of fluidity of sand tailing slurries is significantly higher in the presence of surfactants than the polymer used. It was determined that the particle size distribution has also a very important role on the fluidity and the limit of pumpability of sand tailings.
Effect of residual anionic surfactant on flotation of phosphate ores was also studied. Results indicate that the surfactant used in this investigation did not significantly influence the flotation process at the recommended dosage levels.