Change in particle size distribution of low-rank coal in long-term storage

In the extreme natural climate conditions in the Far North, with multiple zero crossovers of air temperature within a day, the complex circuits of coal shipment involve long periods of haulage and storage. Local coal-fired boiler houses use mainly the technology of fuelbed firing at exclusive standards of coal fineness. This promotes oxidation of coal, change in its particle size distribution, as well as quantitative and qualitative losses. Using the proposed procedure, the changes in coal properties in different long-term storage scenarios are assessed as a case-study of Kangalass lignite (Yakutia). The long-term storage scenarios included storage of ROM and graded coal –10 mm in size, unpacked and packed: in open air; under canopy, with natural ventilation; in underground roadway at unstable negative temperatures of mine air and rock mass. It is found that initial properties of coal and, first of all, its grain size distribution are best preserved in the latter scenario, while the least effective is unpacked coal storage in open air, which enjoys common application. The research findings make it possible to assess the nature of fuel transformation in different conditions. With due regard to the earlier studies, emphasis is laid on advisability of adjustment of current approaches to coal production and shipment chain management in the energy-deficient areas and on development of action plans aimed to mitigate adverse effects.

Fedorov V. I., Gavrilov V. L. Change in particle size distribution of low-rank coal in long-term storage. MIAB. Mining Inf. Anal. Bull. 2021;(12–1):223—232. [In Russ]. DOI: 10.250 18/0236_1493_2021_121_0_223.

Fedorov V. I.¹, Junior Researcher, fonariwe@gmail.com;
Gavrilov V. L.^1,2, Cand. Sci (Eng.), Leading Researcher, gvlugorsk@mail.ru;
¹ Chersky Mining Institute of the North of the Siberian Branch of Russian Academy of Sciences, Yakutsk, Russia, Lenin Ave, 43;
² Chinakal Institute of Mining, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia, Krasny Ave.

Gavrilov V. L., e-mail: gvlugorsk@mail.ru

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