Method for Rapid Sedimentation of Fine Particles from Suspensions.
U S Pat 4 000 067 1976 Dec; :
In the title process, particularly useful in rapid settling of fine mineral particles resulting from beneficiation of phosphate ore, one part slime is treated with at least one part hf, nh4f, and/or h2sif6 at ph 0.5-5.0. Thus, 1 part (based on solids) phosphate slimes from phosphate ore beneficiation is treated with 1 part hf (as a dilute aqueous solution), resulting in onset of settling after 5-10 minutes and settling adequate for filtration after 1 h.
U.S. Pat. 4,000,067; Dec. 28, 1976; Chem. Abstr. 86:78,283Q