The paper presents flotation of two phosphate ore samples of different origin. Statistical analysis was used to study the effect of operating parameters on flotation efficiency. The paper proposes to increase the efficiency of flotation processing of magmatic phosphate ore with a low grade of the valuable component (P2O5 = 10.88 %), containing nepheline and feldspars, by means of direct anionic flotation. Authors present an optimization of anionic flotation using tall oil fatty acids mixed with anionic phospholane as an anionic collector. The effect of adding soda ash to compensate for the influence of calcium cations on technological parameters of P2O5 flotation was examined. The results of studying the flotation of nepheline ore (flotation tailings of magmatic phosphate ore) showed that replacement of phospholane with oxyethylated isotridecanol allowed to obtain a high-quality concentrate. It was estimated that with the addition of Na2CO3 in the amount of 2,000 g/t, a concentrate was obtained with the grade and recovery of phosphorus pentoxide equal to 39.15 and 94.19 %, respectively. The paper proposes to increase the efficiency of flotation processing of sedimentary phosphate ore with a low grade of the valuable component (P2O5 = 22.5 %), containing gypsum and quartz, by means of desliming followed by anionic or cationic reverse flotation. Tall oil fatty acid with anionic phospholane was used as a collector in anionic reverse flotation, and amine was used in cationic reverse flotation. Sodium tripolyphosphate was used as a P2O5 depressant. It was found to be an effective depressant in both anionic and cationic flotation. When analyzing the statistical plan, it was estimated that the maximum grade of the valuable component in the concentrate (P2O5 = 31.23 %) and the recovery to concentrate of 95.22 % were obtained in the chamber product at amine consumption of 950.88 g/t and sodium tripolyphosphate consumption of 500 g/t.

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Ultrafine grinding is required in most industrial applications of talc. In this work, a planetary mill was used to produce a d50 product of less than 5 μm. The effects of grinding time, media size, mill filling, rotational speed, and media-to-powder ratio, as the main grinding parameters, were initially investigated by the one-variable-at-a-time strategy. In addition, the statistical design method was applied to optimize and correlate the d90 and d50 of the ground product to the media-to-talc percentage and grinding time, being the most significant variables for talc grinding in a planetary mill. The results indicate that the ball size significantly affects the product fineness up to a certain ball size (i. e., 4 mm), after which the product becomes coarser. At the same time, lower mill filling and higher mill rpm yield finer products. The agglomeration of particles under dry conditions is the main constraint to size reduction below certain limits. The maximum size reduction obtained in grinding with the 85 % media-to-powder ratio, 30 % mill filling, and higher rotational speed (300 rpm) during 30 min grinding cycles was 14.6 μm and 4.5 μm for d90 and d50 of the ground product, respectively.

This paper presents the results of the beneficiation of a phosphorus-bearing mineral through selective flotation process. The chemical examination showed that the sample contain a low content of P2O5 12.5 % and significant amounts of rare earth elements (REE), %: yttrium - 0.01, lanthanum - 0.06, cerium - 0.09, neodymium - 0.03. The particle size distribution of the sample was performed, and each separated fraction was chemically analyzed. A detailed examination of the mineralog ical characteristics was conducted using automated mineral liberation analyzer (MLA). It has been shown that the apatite particles are mostly liberated in all fraction sizes. The maximum percentage of apatite polymineral aggregate was recorded in the grain size of -0.5 + 0.2 mm, mainly with nepheline and pyroxenes. The maximum percentage of apatite binary aggregate was noted in the grain size of -0.16 + 0.071 and -0.071 + 0.045 mm. Based on the obtained results, the size of the flotation feed was predetermined, which allowing the complete liberation of phosphorusbearing mineral (apatite) and avoiding over-grinding of the ore.

The article studies the mineralogical features of phosphate ores. In the conditions of declining industrial reserves of apatite-containing ores, issues of a more comprehensive and in-depth study of the mineral and material composition, as well as the improvement of existing technologies for the processing of this type of raw material, become topical. Using optical methods of analysis, electron microscopy with automated mineralogical analysis (MLA), mineral and elemental composition of apatite was obtained. Taking into account the studied mineralogical and material composition, experiments on grinding and flotation were carried out. Based on these data, it was concluded that the optimal scheme for the processing of phosphate ores is a flotation scheme with preliminary selective disintegration.