Saint-Petersburg Mining University (St. Petersburg, Russia):

Aleksandrova Т. N., Head of Chair, Doctor of Engineering Sciences, Professor, Aleksandrova_TN@pers.spmi.ru
Kuskov V. B., Associate Professor, Candidate of Engineering Sciences, Associate Professor, Kuskov_VB@pers.spmi.ru
Afanasova А. V., Teaching Assistant, Candidate of Engineering Sciences, Afanasova_AV@pers.spmi.ru
Kuznetsov V. V., Postgraduate Student

The paper presents data on the development of a reagent regime for the flotation of fine coal fractions of –0.5+0 mm. The study focuses on coking coal from the Butovskaya mine (Kemerovo coal deposit, Russia). The ash content in the rock mass mined ranges from 23 to 30 %. Using the methods of optical microscopy, the presence of rock-forming minerals in the flotation feed, mainly represented by silicates (quartz), was established, which supports the addition of liquid glass to the process as a depressant for silicates. The study of the flotation kinetics allowed establishing the coal flotation time for a more complete recovery of the combustible matter. The paper compares the basic and alternative reagent regimes. The basic regime is represented by an apolar collector in the form of a mixture of hydrocarbon liquids of petroleum origin and a frother containing oxygen-bearing chemical compounds of various molecular structures in its group chemical composition. The alternative regime includes a depressant (liquid glass), an apolar collector (diesel fuel), and a frother represented by a mixture of aliphatic alcohols, ethers, and esters. Using the technology developed, coal flotation concentrate was obtained with the mass fraction of ash of 7.36 % and recovery of 9.78 %, allowing to generate a product meeting the requirements of GOST R 51588-2000.
The work was carried out with the support of the Russian Science Foundation (project No. 19-17-00096).

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