Author 1:
Name & Surname: Gershenkop A. Sh.
Company: Mining Institute, Kola Science Center, Russian Academy of Sciences (Apatity, Russia)
Work Position: Principal Researcher
Scientific Degree: Doctor of Engineering Sciences
Contacts: alex@goi.kolasc.net.ru

Author 2:
Name & Surname: Mukhina T. N.
Company: Mining Institute, Kola Science Center, Russian Academy of Sciences (Apatity, Russia)
Work Position: Head of subdivision
Scientific Degree: Candidate of Engineering Sciences

Author 3:
Name & Surname: Marchevskaya V. V.
Company: Mining Institute, Kola Science Center, Russian Academy of Sciences (Apatity, Russia)
Work Position: Senior Researcher
Scientific Degree: Candidate of Engineering Sciences

The article presents technological study of large-nodular kyanite schist of the most promising deposit in the Keivy group, Kola Peninsula, aimed to improve the mineral processing. The 2 times larger feed size in float-and-sink separation as against the earlier technology promotes enhancement of technological and economical efficiency of the process stage. The possibility is shown for simplifying the flotation flowsheet due to reduction of one flotation stage branch by simultaneous flotation of feed stock, composed of float-and-sink separation middlings, and ore screening less than 5 mm in size. Based on the physicochemical analysis data, it has been found that selectivity of kyanite flotation in alkaline medium significantly improves when combining polyalkylbenzene sulfonate and crude tall oil soap. The method has been developed for water treatment using aluminum sulfate thus allowing kyanite concentration in circulating water with technological parameters close to ‘fresh’ water. Using the advanced combination gravity–flotation flowsheet with water circulation, kyanite concentrate has been produced, that conforms with the technical specifications of high-alumina concentrate for heatproof ceramics and refractory production. The laboratory test results have proved usability of produced gravity–flotation kyanite concentrates as a basic material for aluminum–silicon alloy and high-duty refractory production.

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