1. To dilute BS-30F before use, one can employy technical water from coal-dressing plant in the industrial Donbass of total hardness <= 9.4 mg-eq/liter and pH in the range 7.8-9.2. Selective flocculation with BS-30F is best performed with typical circulating water of total hardness from 8 to 17 mg-eq/liter and pH = 7.8-9.2. 2. The time required for the total deposition of a coal sludge is dependent on the grade of coal and the floeculant flow rate. 3. When the floeculant contacts the solid, there are hydrophobic interactions of the polymer globules with the surfaces of the coal particles; chains of polymer globules are formed that link the particles into aggregates. In the presence of electrolytes in the liquid, the chains of polymer globules of floeculant coagulate and become rubbery filaments; the bonds between the coal grains are strengthened and relatively large and reasonably strong floccules arise. As the floeculant concentration increases, the electrochemical potential of any grade of coal rises in the positive sense, and the more so the more metamorphosed the coal. 4. When a coal suspension is mixed with the floeculant, an emulsifier is transferred from the polymer globules to the liquid: the potash soap of disproportionated rosin, which is then adsorbed on the mineral grains and favors their stabilization. 5. There is the best value for the Reynolds number (dependence of the selective flotation performance on the mixing intensity) where the propellor mixer is used. Coal floccules begin to form after 15 sec contact of the floeculant with the solid phase. The best time for mixing the sludge with BS-30F has been determined. 6. We consider that a transitional form of structure may arise on structuring a dispersed system additional to the known ones: the flocculation-condensation form. 7. An important resultant parameter for the properties of the liquid in a coal sludge is the resistance to a moving body, which combines the viscosity, the density, and the confinement of the working medium. To reduce the resistance to the motion of coal grains on dressing, it is proposed to reduce the viscosity of the liquid phase by treating it with selective floeculant BS-30F, in which the emulsifier (potash soap of disproportionated rosin) is a surfactant.
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