REC «Mekhanobr-Tekhnika» (St. Petersburg, Russia):
Vaisberg L. A., Company Scientific Advisor, Academician of the Russian Academy of Sciences, Doctor of Engineering Sciences, Professor, gornyi@mtspb.com

Saint Petersburg Mining University (St. Petersburg, Russia):
Kuskova Ya. V., Assistant, Candidate of Engineering Sciences, yana.kuskova@gmail.com

Gravity concentration takes the lead among other mineral processing methods. One of the frequently enough used gravity concentration processes is beneficiation on concentrating tables. Concentrating tables are used for beneficiation of small-size fractions of tin, tungsten, rare and noble metals ores, as well as other minerals. In these apparatuses pulp is moving upon inclined surface under action of gravity with low-depth water flow. A fairly large number of designs of concentrating tables are known, in particular, with circular-shaped decks. At different times, the leading specialists in gravity concentration participated in developmental studies with regard to circular concentrating tables. A considerable amount of the accomplished research and development work permitted to solve such problems as increased precision of materials separation into products, improved beneficiation process parameters, development of new designs of concentrating tables. The results of the newly-designed circular concentrating tables testing are described in this paper. A test rig has been designed and produced at the «Mekhanobr» Institute that includes a damped elastically-mounted superresonance vibration stand with bi-harmonic drive creating swinging oscillations, removable decks and a number of auxiliary units. In the course of the investigations, a number of drawbacks of the concentrating table design deficiencies were revealed, that later were eliminated during the testing and technological works. New designs of circular concentrating tables were developed and tested. The tests results proved a sufficiently high performance and efficiency of the concentrating tables in question. On the basis of these tests, improved designs of circular concentrating tables were developed over the last ten years, providing for increased minerals separation efficiency.
The studies were performed with the aid of the Russian Science Foundation Grant (Project No. 17-79-30056).

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