Author 1:
Name & Surname: Novikov E. A.
Company: Mining Institute of National University of Science and Technology MISiS (Moscow, Russia)
Work Position: Researcher
Scientific Degree: Candidate of Technical Science

Author 2:
Name & Surname: Dobryakova N. N.
Company: Mining Institute of National University of Science and Technology MISiS (Moscow, Russia)
Work Position: Postgraduate student

Author 3:
Name & Surname: Shkuratnik V. L.
Company: Mining Institute of National University of Science and Technology MISiS (Moscow, Russia)
Work Position: Head of Department of Physico-Technical Control in Mining
Scientific Degree: Professor, Doctor of Technical Science
Contacts: e-mail: ftkp@mail.ru

Author 4:
Name & Surname: Epshtein S. A.
Company: Mining Institute of National University of Science and Technology MISiS (Moscow, Russia)
Work Position: Head of Coal Physics and Chemistry Laboratory
Scientific Degree: Professor, Doctor of Technical Science

The article gives an analytical review of the existing methods for assessment of coal oxidation as one of the most important characteristics and a criterion of coal quality. The consideration involves basic standards in use in Russia and abroad for regulation of coal oxidation assessment based on microscopy of polished sectionsbriquettes and optical density of alkaline extracts of coal. Shortcomings of the standards and their common use ranges are described. The authors analyze the existing alternative techniques of coal oxidation assessment based on: generation of humic acids under oxidation decomposition of coal, alterations in thermal decomposition of coal, its sorption properties, conductance, phase composition of iron compounds, etc. Attention is given to methods that use interaction between oxidation level and process variables of coal, such as combustion heat, coking capacity, water content, mass, etc. The article describes the method based on analyzing parameters of heat-stimulated acoustic emission of coal, heat endurance of which is the function of oxidation. It is noticed that none of the discussed methods is universal and enables investigation of oxidation of coal of various types and kinds, or at various levels of oxidation. Low precision of oxidation estimates obtained with different methods is highlighted. It is shown that the efficient assessment of coal oxidation is possible through integration of different methods in order to take into account genesis and metamorphism of coal; chemical activity of coal toward oxidizing agents; endogenous and exogenous damage that conditions access of oxidizing agents to free surface of coal, air permeability and diffusion coefficients; efficient kinetic parameters that characterize intensity of exothermal processes resulting in heating of coal.
The work was supported by the Federal Target Program “Research and Development in Priority Areas of Scientific and Technical Advance in Russia in 2014–2020,” (Agreement No. 14.575.21.0062, unique agreement identification RFMEFI57514X0062).

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