REC «Mekhanobr-Tekhnika» (Russia):

Arsentyev V. A., Doctor of Engineering Sciences, Research and Development Director, ava@npk-mt.spb.ru
Gerasimov A. M., Ph. D. in Engineering Sciences, Researcher, gerasimov_am@npk-mt.spb.ru
Dmitriev S. V., Chief Specialist, dmitriev_sv@npk-mt.spb.ru
Samukov A. D., Chief Project Engineer, samykov_ad@npk-mt.spb.ru

Presently, in high-ash coal beneficiation technologies, used in our country and abroad, mainly «wet» processes are applied, such as hydraulic size grading, gravity separation and flotation. Use of these technologies leads to a number of negative economic and environmental implications. Therefore, development of a scientific basis for an environmentally sound mineral coal beneficiation is of a vital importance. The accomplished study employed a new approach to development of mineral coal beneficiation flow sheet based on thermal modification, permitting to change physical-chemical properties of mineral coal so as to provide for its subsequent processing, including grinding, separation, transportation and storage without industrial water use. X-ray phase analysis and microtomography of coal samples were performed in order to reveal thermal modification effects upon structural and mechanical parameters of coal. Thermochemical modification of mineral coal through medium temperature pyrolysis permits to significantly change its physical-chemical properties, in particular, to decrease specific energy inputs in coal crushing by 20–30 %. Thermal modification of mineral coal changes its structure, increases porosity and alters amorphous and crystalline phases ratio, thus providing conditions for subsequent dry beneficiation of coal.
The study were performed with the aid of the Russian Science Foundation Grant (Project No. 15-17-30015).

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