The beneficiation of oil shales and separation of organic matter (OM) enables expansion of fields of their industrial application. For example the concentrate of OM may be used for separation of dicarboxylic acids for further production of plastics, plasticizers and other chemical products. Due to enrichment in OM in the beneficiation process, oil shales may be used more effectively in both power engineering and oil production. Besides, the separation of calcite allows to reduce emission of carbon dioxide at processing oil shales.
To choose the optimum grinding method to enable most selective separation of OM, different possibilities were tested. The best results, related to further separation of OM in the hydrocycling process, were obtained by using a centrifugal-rebound mill for grinding oil shale. The three-stage hydrocycling of the ground oil shale makes it possible to upgrade the concentrate up to 50.2% OM at high recovery – 91.5% from the feed ore.
Separation of OM was carried out by using the flotation process, and the effect of different parameters was investigated. These included reagent conditions, particle size, pH level and flotation time. After five cleaner flotation of the rough concentrate the product containing 85.7% OM at the recovery of 81.3% from the feed oil shale was obtained.
In this report the general flow sheet involving combined hydrocycling and flotation processes is described. This flow sheet enables to produce a concentrate containing 90% OM at the recovery of 90.9% from the feed oil shale.
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