№60-10

Conversion of the coal microstructure affected by weak electrical fieldaction

T. Pichka1

1Institute for Physics of Mining Processes National Academy of Science of Ukraine, Dnipro, Ukraine

Coll.res.pap.nat.min.univ. 2020, 60:106-115

https://doi.org/10.33271/crpnmu/60.106

Full text (PDF)

ABSTRACT

Purpose. Study of physicochemical changes, which take place in coal microstructure after being treated with low-voltage electric fields.

Methodology. Used coal samples, have follow characteristics: carbon content 86.9%, hydrogen 5.6%, vitrinite reflectance R0 ≥ 1,04 %, Y = 19 мм, W = 1,4%, Vdaf = 31,3%, combustion heat Qdaf = 35560 kJ/kg. Low voltage electric fields up to 200 V/cm were used. Physicochemical characteristics study was carried out in research laboratories of SE NPP "Pavlograd Chemical Plant" using optical microscopy with differential scanning calorimetry, laser diffraction analysis of particle sizes, infrared spectroscopy and other.

Findings. Experimental studies, included coal samples preparation for electromagnetic treatment. After treatment with weak electric fields, were studied physicochemical changes in treated coal samples. To compare results of coal microparticles electric field treating we can see the tendency in microparticles fractional composition change with weak magnetic field.

The originality.  Effect of changing coal microparticles granularity in a weak electric field was established, it means that microparticles content increases in size, when largest in size decreases. This effect based on the fact that deformed (destabilized) chemical bonds excitation, even with low electric field strength; it leads to microparticles destruction and corresponding gas generation. Weak magnetic field impact leads to repeated increase of maximum grain size in microparticles size. Assumed that magnetic fields action stimulates spin-selective chemical reactions between moving components and microparticles surfaces.

Practical implications are that s obtained experimental result will be useful for physico-mathematical modeling of solid phase fracture mechanisms, not only under thermobaric influences, but also of weak electric fields tensions. Particular importance of these works in new non-energy-intensive technologies development for processing coal into gas and liquid components.

Keywords: microstructure destabilization, destructuring, field strength, chemical activity.

References:

1. Alekseev, A.D. (2010). Fizika uglya i gornykh protsessov. Kyiv: Naukova dumka.

2. Sobolev, V., Molchanov, A., & Rudakov, D. (2019). Physicochemical transformations in coals induced by electric fields .Norderstedt. LAPLAMBERT Academic Publishing.

3. Mineev, S.P., Potapenko, A.A., Mkhatvari, T.Ya. i dr.. (2013). Povyshenie effektivnosti gidravlicheskogo rykhleniya vybrosoopasnykh ugol'nykh plastov. Donetsk «TOV «Skhidnyi vydavnychyi dim».

4. Khomenko, O.E. (2016). Geoenergektika podzemnoy razrabotki rudnykh mestorozhdeniy: monografiya. Dnepropetrovsk: NGU.

5. Panchenko, E.M. (2009). Elektretnoe sostoyanie v oksidakh. Moskva: Fizmatlit.

6. Pivnyak, G.G., Sobolev, V.V., & Baskevich, A.S. (2012). Ustoychivost' uglerodsoderzhashchikh faz v uglyakh pri prokhozhdenii slabogo elektricheskogo toka. Dop. NAN Ukrainy, 2,107-113.

7. Sobolev, V.V. (2010). Zakonomernosti izmeneniya energii khimicheskoy svyazi v pole tochechnogo zaryada. Dop. NAN Ukraїni, 4, 88-95.

8. Soboliev, V., Bilan,N., Filippov,A., Baskevich,A. (2011). Electric stimulation of chemical reactions in coal. Теchnical and Geoinfоrmational systems in Mining, 125-130.
https://doi.org/10.1201/b11586-21

9. Sobolev, V.V. (2003). K voprosu o prirode obrazovaniya vybrosoopasnykh ugley. Sbornik nauchnykh trudov NGU, Т.1, 17, 374-383.

10. Soboliev,V., Bilan,N., & Samovik,D. (2013).Magnetic stimulation of transformations in coal. Mining of Mineral Deposits, 221-225.

11. Pivnyak, G.G., Sobolev, V.V., & Filippov, A.O. (2012) Phase transformations in bituminous coals under the influence of weak electric and magnetic fields. Naukovyi Visnyk Natsionalnoho Hirnychoho Universytetu, Vol. 5, 43-49.

12. Frolkov, G.D., Fandeev, M.I., Malova, G.V., Frolkov, A.G., Frantsuzov, S.A., & Sobolev, V.V. (1997).Effect of natural mechanical activation on coal blow-up hazards. KhimiyaTverdogoTopliva, Issue 5, 22-33.

13. Sobolev, V.V., Bakskevich, A.S., Bilan, N.V., & Filippov, A.O. (2011). Ustoychivost' nanostruktury kamennogo uglya pri vozdeystvii elektricheskogo toka.Naukovyi visnyk NHU, 6, 80-84.

14. Molchanov, O., Rudakov, D., Soboliev, & V., Kamchatnyi, O. (2018). Destabilization of the hard coal microstructure by a weak electric field. E3S Web of Conferences, 60, 00023.
https://doi.org/10.1051/e3sconf/20186000023

15. Sobolev,V.V., Rudakov,D.V., Molchanov,O.M., Stefanovych, L.I., & Kirillov, A.K. (2019). Physical and chemical transformations in gas coal samples influenced by the weak magnetic field.Naukovyi Visnyk Natsionalnoho Hirnychoho Universytetu, 6, 52-58.
https://doi.org/10.29202/nvngu/2019-6/8

16. Rudakov, D., & Sobolev, V. (2019). АMathematical Model of Gas Flow during Coal Outburst Initiation. International Journal of Mining Science and Technology,791-796.
https://doi.org/10.1016/j.ijmst.2019.02.002

17. Alekseev, A.D., Ayruni, A.T., & Zverev, I.V. (1994). Fiziko-tekhnicheskie problemy razrabotki poleznykh iskopaemykh. 5, 65-70.

18. Sobolev, V.V., Polyashov, A.S., & Zberovskiy, V.V. (2013). Sistema ugol'-gaz v uglevodorodakh ugol'nogo genezisa. Dnepropetrovsk: ART-PRESS.

19. Alekseev, A.D., Shatalova, G.E., Ul'yanova, E.V., & Degtyar', S.E. (2003). Rentgenostrukturnye issledovaniya stroeniya prirodnykh ugley. Sb. nauchn. tr. Natsional'nogo gornogo universiteta, 17, 26-30.

20. Sobolev, V.V., Chernay, A.V., & Chernyak, S.A. (2006). Rol' elektricheskogo toka v stimulirovanii destruktivnykh protsessov v kamennom ugle. Izvestiya vysshikh uchebnykh zavedeniy. Severo-Kavkazkiy region. Tekhn. Nauki, pril. 9, 45-51.

21.  Butyagin, P.Yu. (1971). Kinetika i priroda mekhanokhimicheskikh reaktsiy. Uspekhi khimii, T. 40, 1935-1959.

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