Joint Institute for High Temperatures of RAS (Moscow, Russia):

Ryabov Yu. V., Senior Researcher, Candidate of Engineering Sciences, ryabov1938@yandex.ru
Delitsyn L. M., Chief Researcher, Doctor of Geological and Mineralogical Sciences, delitzin@ihed.ras.ru
Ezhova N. N., Leading Engineer, Candidate of Chemical Sciences, nnejova@mail.ru

Institute of Comprehensive Exploitation of Mineral Resources of RAS (Moscow, Russia):
Lavrinenko A. A., Head of Laboratory, Doctor of Engineering Sciences, la-vrin_a@mail.ru

The Russian Academy of Sciences United Institute of High Temperatures is currently developing a technology for complete recycling of coal-fired power plants furnace-waste that is normally removed by a wet method, setting the highest premium on unburned carbon separation through flotation. Consumption of collecting agents, conventionally applied in mineral carbon flotation beneficiation, is quite high, due to increased porosity and reduced adsorption-active surface of unburned carbon particles. In order to increase economical efficiency of unburned carbon flotation process, experiments were performed with addition of PAV-2 conditioning agent to reagents mix prior to dosing of collector (kerosene, heavy distillate polymer, motoalkylate, a mixture of heavy vacuum gas oil with kerosene) and frother (pine oil). It is shown that addition of PAV-2 does not produce a detectable effect upon flotation efficiency index, when heavy distillate polymer is used as collector (being most flotoactive among the studied reagents). In unburned carbon flotation with kerosene, addition of PAV-2 in the quantity of 1 g/t permits to significantly reduce consumption of collector. Further increase in consumption of PAV-2 leads to depression of flotation, as in the case of coal slime flotation. However, the results of the experiments with other collectors show, that increase in consumption of PAV-2 does not lead to depression of flotation, in contrast to coal slime flotation. Upon the whole, the decreasing tendency to lower consumption of collectors is observed with application of PAV-2.

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