Sedimentation and separation of red mud is an extremely complicated phsical and chemical process.the Bayer process dissolving pulp is a suspension formed by red mud and sodium aluminate solution.Due to the complex physical and chemcial interactions between the red mud particles and the solution,the phase compositon, distribution, surface morphology of red mud particles, soild content of red mud slurry,liquid phase compositon,red mud slurry temperature,etc.all have significant effects on the sedimentation and separation process of red mud slurry.

       By adding specific flocculant can greatly increase the settle speed of soild-liquid separation.The mechanism of high-molecular flocculants lies in the effective coagulation between the red mud particles through adsorption bridges, surface adsorption and charge meutralization,and the foemation of "large particles",which greatly accelerates the setting velocity.Different dissolution are puplps have different properties,and the appropriate polymer floccukants must be selected through esperiments before achieving high efficient separation of red mud on site.