Sklyar L. Peculiarities of nodular phosphorite ores beneficiation.

The thesis deals with determining characteristic properties of nodular phosphorite ores complex dressing in order to develop complex technology of the raw materials processing. Some mechanisms of ore flotation properties change due to structural characteristic properties of water when it is heated or cooled have been established as well as entropy change amount has. There has been proposed a frankolite flotation kinetic model which takes into account energy barrier of water frame and energy of surface tightening at the edge of the three phases separation. Some special characteristic properties of surface activation of minerals and their behaviour under different temperature conditions have been determined. Concentrates being subjected to thermal treatment, a thermodynamic analyses of balance system composition was carried out. It has been revealed that phosphorus passes into condensable phase in the form of triabasic calcium phosphate in flotation concentrates produced from ores with low carbonate module. With high carbonate module ore being subjected to thermal treatment, it is impossible to produce concentrates with more than 30% phosphorus oxide mass proportion without phosphoruscontaining minerals being activated. Activation of minerals surface with sulfuric acid (H2SO4) allows to change surface behaviour and increase the rate of filtrate flow of phosphorites 25 times.