ESTONIAN ACADEMY
PUBLISHERS
eesti teaduste
akadeemia kirjastus
PUBLISHED
SINCE 1984
 
Oil Shale cover
Oil Shale
ISSN 1736-7492 (Electronic)
ISSN 0208-189X (Print)
Impact Factor (2020): 0.934

COMPARATIVE STUDY OF PYROLYSIS AND THERMAL DISSOLUTION OF ESTONIAN AND MONGOLIAN KHOOT OIL SHALES; pp. 329–339

Full article in PDF format | doi: 10.3176/oil.2016.4.02

Authors
BARNASAN PUREVSUREN, PUNSALMAA OCHIRBAT

Abstract

Two oil shale (OS) samples with different organic matter (OM) con­tent from the Khoot deposit, Mongolia were characterized, their pyrolysis and thermal dissolution experiments were carried out and the results compared with those obtained for the Estonian oil shale sample in the same experimental conditions. The thermal decomposition of the organic matter of oil shale samples starts in the temperature range of 200–300 °C, while the highest yield of liquid products (tar and pyrolysis water) and the lowest yield of solid residue are obtained at 500–600 °С, which can be considered an optimal temperature range for the pyrolysis of OS samples. In this tem­perature region, 23% of tar is obtained from the Estonian oil shale sample, which is more than the yield from Mongolian Khoot oil shale samples. The higher tar yield from the Estonian oil shale sample is due to its lower ash and higher organic content compared to Mongolian Khoot oil shale samples.
     The results of the thermal dissolution experiments for the three OS samples show that the yield of liquid product (tar) is the lowest at 350 °С, the highest at 400 °С and lower again at 450 °С. So, 400 °С can be considered an optimal temperature for the thermal dissolution of all the samples in tetralin as a hydrogen-donor solvent. The optimal temperature of thermal dissolution decreased almost 200 °С compared to that of pyrolysis due to the use of an autoclave, which is more suitable for carrying out the thermal decomposition of oil shale organic matter than the retort. Also, the yield of tar upon thermal dissolution is higher than that in pyrolysis, because the hydrogen in tetralin molecules favours its formation.


References

1.      Kuznetsov, D. T. World Oil Shales, Nedra, Moscow, 1975 (in Russian).

2.      Altun, N. E., Hiçyilmaz, C., Hwang J., Y., Suat Bağci, A., Kök, M., V. Oil shales in the world and Turkey; reserves, current situation and future prospects; a review. Oil Shale, 2006, 23(3), 211–227.

3.      Kök, M. V., Pamir, R. Pyrolysis kinetics of oil shales determined by DSC and TG/DTG. Oil Shale, 2003, 20(1), 57–68.

4.      Kok, M. V., Şenguler, İ. Geological and thermal characterization of Eskişehir region oil shales. J. Therm. Anal. Calorim., 2014, 116(1), 367–372.
https://doi.org/10.1007/s10973-013-3537-x

5.      Kök, M. V. Evaluation of Turkish oil shales - thermal analysis approach. Oil Shale, 2001, 18(2), 131–138.

6.      Bolormaa, Kh. Study of Oil Shales in Central Economic Region of Mongolia. Report, Mineral Resources Authority, Mongolia, Ulaanbaatar, 1997 (in Mongolian).

7.      Avid, B. Chemical Investigation of the Oil Shale from Khoot Deposit. PhD Thesis, Ulaanbaatar, Mongolia, 1999 (in Mongolian).

8.      Avid, B., Purevsuren, B., Dugarjav, J. Pyrolysis and thermogravimetric inves­tigation of the Mongolian Khoot oil shale. Oil Shale, 2000, 17(3), 241–251.

9.      Avid, B., Born, M., Purevsuren, B., Undrakh, N., Tuvshinjargal, A. Thermal behavior of the Khoot oil shale in different conditions. Oil Shale, 2003, 20(1), 47–55.

10. Avid, B., Purevsuren, B. Investigation of mineral matter of the Mongolian Khoot oil shale. Oil Shale, 2002, 19(1), 35–42.

11. Avid, B., Purevsuren, B. Chemical composition of organic matter of the Mongolian Khoot oil shale. Oil Shale, 2001, 18(1), 15–23.

12. Avid, B., Purevsuren, B., Paterson, N., Zhuo, Y., Peralta, D., Herod, A., Dug­well, D. R., Kandiyoti, R., An exploratory investigation on the performance of Shivee-Ovoo coal and Khoot oil shale from Mongolia. Fuel, 2004, 83(7–8), 1105–1111.
https://doi.org/10.1016/j.fuel.2003.11.001

Johannes, I., Tiikma, L., Luik, H., Tamvelius, H., Krasulina, J. Catalytic thermal liquefaction of oil shale in tetralin. ISRN Chemical Engineering, 2012, 1–11, 10.5402/2012/617363.
https://doi.org/10.5402/2012/617363


Back to Issue