Mining Institute, Kola Science Centre of the RAS (Apatity, Russia):
Khokhulya M. S., Leading Researcher, Candidate of Engineering Sciences, m.hohulya@ksc.ru
Fomin A. V., Researcher, fomin5-49@mail.ru

The effect of segregation of mineral particles is one of the essential mechanisms in a number of gravity separation methods, including spiral separation. Research into this phenomenon therefore plays a significant role in studying the regularities in ore and material separation in spiral separators. The regularities of spiral separation have not been sufficiently studied to date, despite the fact that this process has long been used in processing technologies. Numerical simulations based on the mathematical methods of computational fluid dynamics were used to study the regularities in iron ore segregation in spiral separators of various designs. It has been shown that density-based segregation of mineral particles occurs along the height of the suspension flow, where particles with the highest density accumulate in the bottom layer. The authors propose a method for quantifying segregation in thin helical flows based on the use of a numerical model of the spiral separation process, as well as the Hancock–Luyken separation efficiency criterion. It has been established that the use of spiral separators with a cross-sectional profile in the form of a slightly inclined curve promotes intensified segregation of hematitecontaining mineral raw materials generated in the processing of ferruginous quartzites of the Zaimandrovskaya group of deposits. It has been found that segregation efficiency in spiral separators for this material increases with higher solids content in the initial feed. The paper also shows the dependence between the segregation efficiency and the number of turns of the spiral separator.

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