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Information × Registration Number 0220U100799, 0117U004045 , R & D reports Title Development of static flocculator with high shear rate for concentrated technogenic suspensions processing to increase the speed of their gravity thickening and water loss popup.stage_title Head Rulov Mykola M., Registration Date 28-01-2020 Organization F. D. Ovcharenko Institute of Biocolloidal Chemistry NAS of Ukraine popup.description2 Separation of solid waste from the aqueous phase of technogenic suspensions (with the aim of returning water for reuse) is mainly carried out by gravity in radial thickeners. To accelerate this The process uses water-soluble polymers (flocculants) and special mixing agents (flocculators), which provide the formation of rapidly settling floccules consisting of suspended solids particles. Before it was found that for the effective treatment of concentrated suspensions in the flocculator there should be an optimum shear rate, which is in the range of 500-1000 s -1, depending on the concentration and dispersion of the suspension. Because the industry uses static flocculators in which the shear rate does not exceed 100 s -1 , there was a need for a more thorough study of the flocculation process of concentrated thin- and ultra- of dispersed suspensions in static flocculators of various types (volumetric and tubular) in order to offer the design of effective flocculators, providing optimal mode of hydrodynamic processing of suspensions. As a result of the above-mentioned research, the following results and conclusions were obtained:  The dispersion and concentration of the suspension significantly affect the efficiency of its flocculation in a tubular-type static flocculator. In the case of ultrafine suspension of calcium carbonate (particle size less than 7 microns) there is a pronounced maximum dependence of flocculation efficiency on the shear rate in the shear rate range 400 - 450 s -1. When increasing the concentration of calcium carbonate suspension to the level of 70 g / l and more appears a secondary maximum flocculation efficiency in the shear rate of about 950 s -1, which is explained by the higher dissolution rate of the flocculant and the corresponding increase in the adhesion of particles in the flocculas, counteracting the destructive flocculus viscous forces.  Product Description popup.authors popup.nrat_date 2020-04-02 Close