Method for determining the ultimate sorption capacity of coal matter by EPR-spectroscopy
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- Category: Content №1 2023
- Last Updated on 25 February 2023
- Published on 30 November -0001
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Authors:
K.A.Bezruchko*, orcid.org/0000-0002-3818-5624, Institute of Geotechnical Mechanics named by N.Poljakov of National Academy of Sciences of Ukraine, Dnipro, Ukraine, e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.
O.V.Burchak, orcid.org/0000-0001-9114-8585, Institute of Geotechnical Mechanics named by N.Poljakov of National Academy of Sciences of Ukraine, Dnipro, Ukraine
L.I.Pymonenko, orcid.org/0000-0002-5598-6722, Institute of Geotechnical Mechanics named by N.Poljakov of National Academy of Sciences of Ukraine, Dnipro, Ukraine
V.V.Chelkan, orcid.org/0000-0002-0733-8739, Institute of Geotechnical Mechanics named by N.Poljakov of National Academy of Sciences of Ukraine, Dnipro, Ukraine
* Corresponding author e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.
Naukovyi Visnyk Natsionalnoho Hirnychoho Universytetu. 2023, (1): 005 - 009
https://doi.org/10.33271/nvngu/2023-1/005
Abstract:
Purpose. Improving the method for determining the ultimate sorption capacity of coal matter using EPR-spectroscopy (electron paramagnetic resonance) by adjusting the proportionality coefficient between the ultimate sorption capacity of coal and the concentration of paramagnetic centers and the conjugation coefficient in accordance with the degree of coalification.
Methodology. The ultimate sorption capacity of the matter was estimated by EPR-spectroscopy, based on the content of paramagnetic centers (PMC) in coal, which are able to come into physical (sorption) interaction with molecules of paramagnetic gas (O2) when the pressure increases. Processing of the research results was carried out by methods of mathematical statistics.
Findings. Analysis of long-term results for determining the ultimate sorption capacity of coal matter by EPR-spectroscopy was carried out. The analysis testified about the need to adjust the proportionality coefficient between the ultimate sorption capacity of coal and the concentration of paramagnetic centers Na and the conjugation coefficient Ksc, depending on the coal rank metamorphism. The values of the proportionality coefficient by hard coal ranks for the yield of volatile components Vdaf and the reflectivity of vitrinite R° were calculated. Appropriate changes were made to the express-method for estimating the ultimate sorption capacity of coal by the EPR method.
Originality. It is proved that the proportionality coefficient β between the ultimate sorption capacity of coal and the concentration of paramagnetic centers Na and the conjugation coefficient Ksc is not a constant value, but changes (decreases) with the degree of metamorphism. It is established that this relationship is satisfactorily characterized by the sigmoid model, whose inflection (on the graph) is confined to the gas and fat ranks of coals (volatile-matter yield is 29 %) and is caused by the second main jump of coalification during a cardinal change in the molecular structure of coal, associated with the completion of the intensive decomposition of the polymer-lipoidin component in the coal matter.
Practical values. The express-method was improved for estimating the ultimate sorption capacity of coal by the EPR-method, which differs by specified proportionality coefficients according to ranks in the series of coalification.
Keywords: coal matter, EPR-spectroscopy, concentration of paramagnetic centers, conjugation coefficient, sorption capacity
References.
1. Zhang, L., Ye, Zh., Li, M., Zhang, C., Bai, Q., & Wang, C. (2018). The binary gas sorption in the bituminous coal of the Huaibei Coalfield in China. Adsorption Science & Technology, 36(9-10), 1612-1628. https://doi.org/10.1177/0263617418798125.
2. Kumar, H., Mishra, M. K., & Mishra, S. (2019). Sorption capacity of Indian coal and its variation with rank parameters. Journal of Petroleum Exploration and Production Technology. https://doi.org/ 10.1007/s13202-019-0621-1.
3. Wen, Zh., Yang, Yu, Wang, Q., & Yao, B. (2021). Mechanism and characteristics of CH4/CO2/H2O adsorption in lignite molecules. https://doi.org/10.1155/2021/5535321.
4. Perera, M. S. A., Ronjith, P. G., Choi, S. K., Airey, D., & Weniger, P. (2012). Estimation of Gas Adsorption Capacity in Coal: A Review and an Analytical Study. International Journal of Coal Preparation and Utilization, 32(1), 25-55. https://doi org/10.1080/19392699.2011.614298.
5. Gao, D., Hong, L., Wang, J., & Zheng, D. (2019). Adsorption simulation of methane on coals with different metamorphic grades. https://doi.org/10.1063/T5115457.
6. Dong, K., Zhai, Zh., & Guo, A. (2021). Effects of Pore Parameters and Functional Groups in Coal on CO2/CH4 Adsorption. ACS Omega, 6, 32395-32407. Retrieved from https://pubs.acs.org/journal/acsodf.
7. Ekundayo, J. M., & Rezaee, R. (2019). Volumetric measurements of methane-coal adsorption and desorption isotherms – effects of equations of state and implication for initial gas reserves. Energies, 12. https://doi.org/10.3390/en12102022.
8. Raharjo, S., Bahagiarti, S., Purwanto, H. S., & Rahmad, B. (2018). The effect of coal petrology on the capacity of gas methane absorption in coal formation Tanjung Barito in Binuang Region, South Kalimantan. Series: Earth and Environmental Science, 212, 012029. https://doi.org/10.1088/1755-1315/212/1/012029.
9. Okolo, G. N., Everson, R. C., Neomagus, H. W. J. P., Sakurovs, R., Grigore, M., & Bunt, J. R. (2019). Dataset on the carbon dioxide, methane and nitrogen high-pressure sorption properties of South African bituminous coals. Elsevier, 25, 40-53. https://doi.org/10.1016/j.dib.2019.104248.
10. Czerw, K., Dudzińska, A., Baran, P., & Zarębska, K. (2019). Sorption of carbon dioxide on the lithotypes of low rank coal. Adsorption, 25, 965-972. https://doi.org/10.1007/s10450-019-00122-5.
11. Wojtacha‑Rychter, K., Howaniec, N., & Smoliński, A. (2020). Effect of porous structure of coal on propylene adsorption from gas mixtures. Scientific reports. https://doi.org/10.1038/s41598-020-67472-x.
12. Dutka, B. (2021). Effect of depth on the sorption capacity of coals affected by outburst hazard. Energies, 306. https://doi.org/10.1016/j.fuel.2021.121.611.
13. Godyn, K., Dutka, B., Chuchro, M., & Młynarczuk, M. (2020). Synergy of Parameters Determining the Optimal Properties of Coal as a Natural Sorbent. Energies, 13, 1967. https://doi.org/10.3390/en13081967.
14. SOU 10.1.00174088.011-2005 Rules for conducting mining operations in strata prone to gas-dynamic phenomena (2005). Kyiv: Minvuhleprom Ukrainy. Retrieved from https://issuu.com/mitc2/docs/026.
15. Rudko, H. I., Bulat, A. F., & Kuznetsova, L. D. (2015). Methodological recommendations for the geological study on the gas-bearing capacity of coal seams and host rocks for the calculation of reserves and the assessment of gas (methane) resources of underground coal deposits, (pp. 106-112). Kyiv: Institute of Geotechnical Mechanics named by N. Poljakov of National Academy of Sciences of Ukraine. Retrieved from https://www.nas.gov.ua/EN/Book/Pages/default.aspx?BookID=0000009846.
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