Math modeling of particle movements in a friction separator

Abstract

<jats:p>A mathematical model of particles movement of separated material in a friction separator is proposed. It includes equations of their movement at each stage of separation (along a rough inclined plane, on a curvilinear part of a springboard, impact of a particle on the surface of a drum, free motion before leaving the separation zone), and differential equations of particle movement in circulating air flow created by a rotating drum; Each of these phases of motion is described by a system of equations obtained on the basis of basic laws of mechanics. An analysis of a particle motion along aslope plane was carried out on the basis of the law on energy changes. Depending on the ratios of the recovery factor and instantaneous friction, being random variables and also the coordinates of a point impact the particle is possible to move along different trajectories with different initial conditions. The mathematical model of the process of separation of loose multicomponent materials on a friction drum-shelf separator makes it possible to investigate comprehensively the process of separation of particles on friction and elastic properties and to optimize the operating modes of the apparatus at relatively low costs without using macaques and prototypes and investigate them experimentally. On the basis of analysis of the proposed theories of particles motion, the main ways are formulated of further improvement of methodology for designing and creating friction devices.</jats:p>

Laboratory evaluation of a complex treatment technology for reducing water absorption of the pavement subbase aggregate from the blast-furnace slag

“…The issues of reducing water absorption of the construction and building materials are considered in a large number of papers [30][31][32][33][34][35][36][37][38][39][40]. To reduce water absorption of materials, various researchers suggest methods such as the use of nano-TiO2-modified recycled coarse aggregate [30], using the air entraining agent (for mortars) [31], slurry coating modified methods (for recycled coarse aggregate) [32], silane emulsion impregnation [33], cement-silica fume slurry coating method [34], compression casting method (to reduce water absorption properties of concrete) [35], impregnation with spent technical fluids [36], selective crushing [1], enrichment in heavy media [37], jigging [38], porosity enrichment on the friction classifier [39], etc. There is also a known method for reducing water absorption of liquid BFS , including pouring it with a thin layer for faster solidification [40].…”