FIELD: technological processes.
SUBSTANCE: disclosed group of inventions relates to devices and methods of separating fine coal particles from ash-forming component particles. Method of separating coal particles from particles of ash-forming components includes formation of bubbles inside water in a flotation cell, introduction of an aqueous suspension of coal fines containing more than 35 wt% of solid particles containing discrete particles of coal and discrete particles of ash-forming components into bubbles inside said flotation cell for coal in such a way, that bubbles capture and flotation of coal particles and form coal foam, wherein coal fines in water suspension has particle size of less than about 750 mcm and collection of carbon foam. Carbon foam contains at least 15 wt% solid particles. Solid particles contain coal particles and ash-forming component particles with flotation efficiency of more than 92 % so that coal particles in coal foam represent extraction of combustible mass of coal fines of more than 90 %. Less than 5 wt% of solid particles are particles of ash-forming components. According to one version of the method of separating coal particles from particles of ash-forming components, formation of bubbles inside water in the flotation cell for coal is carried out by one or more bubble generators, wherein the bubble generators contain a porous material having an average pore size of less than 30 mcm, wherein bubbles are formed and aqueous suspension is introduced into bubbles so that flotation rate of coal foam is more than 1.5 metric tons/h/m2 in terms of dry weight. During separation of particles of ash-forming components from coal particles, carbon foam height of less than approximately 18 inches (0.45 m) is maintained.
EFFECT: high efficiency of separating fine coal particles from ash-forming components.
33 cl, 15 dwg, 4 tbl, 17 ex
Authors
Dates
2019-07-01—Published
2015-09-17—Filed