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Study on the gas desorption law and indicator influencing factors of fixed-size coal samples

The prediction of dangerous hazards in working faces is an important link to prevent coal and gas outbursts. Improving the accuracy of predictive indicators is of great significance for reducing the phenomenon of being prominently below the critical value and ensuring safe production. The fixed-size...

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Autores principales: Li, Lei, Sun, Zhongguang, Wang, Fakai, Zhang, Kaizhi
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Nature Publishing Group UK 2019
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6868149/
https://www.ncbi.nlm.nih.gov/pubmed/31748537
http://dx.doi.org/10.1038/s41598-019-53211-4
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author Li, Lei
Sun, Zhongguang
Wang, Fakai
Zhang, Kaizhi
author_facet Li, Lei
Sun, Zhongguang
Wang, Fakai
Zhang, Kaizhi
author_sort Li, Lei
collection PubMed
description The prediction of dangerous hazards in working faces is an important link to prevent coal and gas outbursts. Improving the accuracy of predictive indicators is of great significance for reducing the phenomenon of being prominently below the critical value and ensuring safe production. The fixed-size desorption index K(1) is one of the important indicators for coal face and gas outburst prediction. Based on the diffusion theory and the physical meaning of fixed-size coal samples, the mathematical expression of K(1) is established by the self-developed high/low temperature pressure swing adsorption-desorption experimental system. According to the equation, the effects of gas pressure, loss time, coal particle size and diffusion coefficient on K(1) are studied. The results show that the K(1) index is logarithmically related to the gas pressure. Under the same conditions, the longer the loss time is, the smaller the measured K(1) is, and the smaller the particle sizes of the drill cuttings are, the more notable the performance is; the diffusion coefficient represents the ability of gas to bypass micropores and the coal matrix. The greater the ability to bypass the matrix is, the larger the diffusion coefficient under the same conditions is, and the larger K(1) is; the coal particle size has a greater influence on K(1), and the smaller the size is, the more likely it is that the phenomenon of being prominently below the critical value occurs. Therefore, the particle size composition of coal during on-site measurements is crucial for obtaining the true K(1) and the exact critical values.
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spelling pubmed-68681492019-12-04 Study on the gas desorption law and indicator influencing factors of fixed-size coal samples Li, Lei Sun, Zhongguang Wang, Fakai Zhang, Kaizhi Sci Rep Article The prediction of dangerous hazards in working faces is an important link to prevent coal and gas outbursts. Improving the accuracy of predictive indicators is of great significance for reducing the phenomenon of being prominently below the critical value and ensuring safe production. The fixed-size desorption index K(1) is one of the important indicators for coal face and gas outburst prediction. Based on the diffusion theory and the physical meaning of fixed-size coal samples, the mathematical expression of K(1) is established by the self-developed high/low temperature pressure swing adsorption-desorption experimental system. According to the equation, the effects of gas pressure, loss time, coal particle size and diffusion coefficient on K(1) are studied. The results show that the K(1) index is logarithmically related to the gas pressure. Under the same conditions, the longer the loss time is, the smaller the measured K(1) is, and the smaller the particle sizes of the drill cuttings are, the more notable the performance is; the diffusion coefficient represents the ability of gas to bypass micropores and the coal matrix. The greater the ability to bypass the matrix is, the larger the diffusion coefficient under the same conditions is, and the larger K(1) is; the coal particle size has a greater influence on K(1), and the smaller the size is, the more likely it is that the phenomenon of being prominently below the critical value occurs. Therefore, the particle size composition of coal during on-site measurements is crucial for obtaining the true K(1) and the exact critical values. Nature Publishing Group UK 2019-11-20 /pmc/articles/PMC6868149/ /pubmed/31748537 http://dx.doi.org/10.1038/s41598-019-53211-4 Text en © The Author(s) 2019 Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.
spellingShingle Article
Li, Lei
Sun, Zhongguang
Wang, Fakai
Zhang, Kaizhi
Study on the gas desorption law and indicator influencing factors of fixed-size coal samples
title Study on the gas desorption law and indicator influencing factors of fixed-size coal samples
title_full Study on the gas desorption law and indicator influencing factors of fixed-size coal samples
title_fullStr Study on the gas desorption law and indicator influencing factors of fixed-size coal samples
title_full_unstemmed Study on the gas desorption law and indicator influencing factors of fixed-size coal samples
title_short Study on the gas desorption law and indicator influencing factors of fixed-size coal samples
title_sort study on the gas desorption law and indicator influencing factors of fixed-size coal samples
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6868149/
https://www.ncbi.nlm.nih.gov/pubmed/31748537
http://dx.doi.org/10.1038/s41598-019-53211-4
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