REC «Mekhanobr-Tekhnika» (St. Petersburg, Russia):

Gerasimov A. M., Senior Researcher, Candidate of Engineering Sciences, gerasimov_am@npk-mt.spb.ru
Lazareva V. V., Senior Research Engineer, lazareva_vv@npk-mt.spb.ru
Arsentyev V. A., Chief Researcher, Doctor of Engineering Sciences, secretariat@npk-mt.spb.ru

Layered silicates, mainly composed by clay minerals, are associated with numerous mineral deposits, since these account for approximately 50 % of all sedimentary rocks. At the same time, layered silicates may be both non-metallic minerals (kaolin, bentonite, talc, vermiculite, glauconite) and components of the host rocks. The main factors behind their effect on the concentration processes are the dispersion ability and the anisotropy of mineral particles obtained by the disintegration of minerals. The presence of layered silicates with mobile crystal lattices in the mined ore significantly complicates both its wet and dry processing. Most methods aimed to reduce their impact on mineral processing have the same disadvantage: while solving the problems at some stages of the process flow, they seriously complicate respective downstream processes. A promising solution, aimed at the efficient use of resources in the processing of ores containing layered silicates, implies the inclusion of thermal and hydrothermal modification of such ores as the primary stages of the process chain. These modifications would ensure a reduction or elimination of the negative impact of such materials currently experienced in ore preparation, separation and dewatering and in the storage of processing products. The use of microwave heating enables changing the structure and processing behavior of ores containing layered silicates at lower material temperatures than in convective heating, which contributes to lower energy consumption for the thermal modification of ores.
Financial support was provided by the Russian Scientific Fund (project 18-17-00169).

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