International Scientific Journal

Thermal Science - Online First

online first only

Synergistic effect of potassium and calcium ions on coal pyrolysis behaviors: Experimental and kinetic model investigations

A low rank coal was first used to investigate the synergistic effect of inherent and loaded potassium and calcium ions on the pyrolysis behaviors. The non-isothermal thermal analysis with higher heating rate to medium pyrolysis temperature was carried out by thermogravimetric analyzer (TGA) for the selected raw and treated coal samples. Preliminary experiments conducted show that the particle size smaller than 160 μm can eliminate heat and mass transfer effect, and the most of volatile matter was released by heating the raw coal (R-coal) to 750°C. Moreover, the effect of heating rate, inherent and loaded potassium and calcium on moisture evaporation and devolatilization is systematically investigated, and the devolatilization index (D) is introduced to estimate the activity of pyrolysis process. A comparison among the acid pickling coal (H-coal), acid pickling coal loaded with calcium (H-coal-C) and potassium (H-coal-P) shows that potassium and calcium have improved the inner water holding capacity. Finally, the influence of inherent and loaded potassium and calcium on the kinetic characteristics of volatile matter release stage was studied with Coats-Redfern integral method.
PAPER REVISED: 2022-05-14
PAPER ACCEPTED: 2022-05-17
  1. Katalanbula, H., Gupta, R., Low grade coals: a review of some prospective upgrading technologies, Energy Fuels, 23 (2009), pp. 3392 3405
  2. Yang, X., et al., Effects of K2CO3 and Ca(OH)2 on CO2 gasification of char with high alkali and alkaline earth metal content and study of different kinetic models, Thermal Science, 26 (2022), 1, Part A, pp. 119 133
  3. Zhang, Z., et al., Catalytic Effect of Inherently Water Soluble Sodium on Zhundong Coal Gasification, Science of Advanced Materials, 12 (2020), pp. 1019 1026
  4. Chen, Z., et al., Steam drying of coal. Part 1 Modeling the behavior of a single particle, Fuel, 79 (2000), pp. 961 973
  5. Favas, G., Jackson, W.R., Hydrothermal dewatering of lower rank coals 2 Effect of coal characteristics for a range of Australian and international coals, Fuel, 82 (2003), pp. 56 69
  6. Bergins, C., Kinetics and mechanism during mechanical/thermal dewatering of lignite, Fuel, 82 (2003), pp. 355 364
  7. Zeng, C., et al., Effects of thermal pretreatment in helium on the pyrolysis behaviour of Loy Yang brown coal, Fuel, 84 (2005), pp. 1586 1592
  8. Zeng, C., et al., Effects of pretreatment in steam on the pyrolysis behavior of Loy Yang brown coal, Energy Fuels, 20 (2006), pp. 281 286
  9. Morimoto, M., et al., Low rank coal upgrading in a flow of hot water, Energy Fuels, 23 (2009), pp. 4533 4539
  10. Shui, H., et al., Hydrothermal treatment of a sub bituminous coal and its use in coking blends, Energy Fuels, 27 (2013), pp. 138--144
  11. Zellagui, S., et al., Pyrolysis of coal and woody biomass under N2 and CO2 atmospheres using a drop tube furnace--experimental study and kinetic modeling, Fuel Processing Technology, 148 (2016), pp. 99--109
  12. Zhou, H., et al., Oxygen release and attrition study of MgO supported Cu--Mn compounds as an oxygen carrier, Science of Advanced Materials, 12 (2020), pp. 1782--1789
  13. Montiano, M. G., et al., Kinetics of co--pyrolysis of sawdust, coal and tar, Bioresource Technology, 205 (2016), pp. 222--229
  14. Solomon, P. R., et al., Progress in coal pyrolysis, Fuel, 72 (1993), pp. 587--597
  15. Ofosu, A. K., et al., Preparation and pyrolysis of O--(alkylphenyl) methyl and O--(alkylnaphthyl) methyl Illinois No. 6 coals. Role of dealkylation reaction in gaseous hydrocarbon formation, Energy Fuels, 2 (1988), pp. 511--522
  16. Monthìoux, M., Expected mechanisms in nature and in confined--system pyrolysis, Fuel, 67(1988), pp. 843--847
  17. Solomon, P. R., et al., Cross--linking reactions during coal conversion, Energy Fuels, 4 (1990), pp. 42--54
  18. Wornat, M. J., Nelson, P. F., Effects of ion--exchanged calcium on brown coal tar composition as determined by fourier transform infrared spectroscopy, Energy Fuels, 6 (1992), pp. 136--142
  19. Shibaoka, M., et al., Application of microscopy to the investigation of brown coal pyrolysis, Fuel, 74 (1995), pp. 1648--1653
  20. Sathe, C., et al., Effects of heating rate and ion--exchangeable cations on the pyrolysis yields from a Victorian brown coal, Energy Fuels, 13 (1999), pp. 748--755
  21. Li, C. Z., et al., Fates and roles of alkali and alkaline earth metals during the pyrolysis of a Victorian brown coal, Fuel, 79 (2000), pp. 427--438
  22. Wu, H., et al., Volatilisation and catalytic effects of alkali and alkaline earth metallic species during the pyrolysis and gasification of Victorian brown coal, Part III The importance of the interactions between volatiles and char at high temperature, Fuel, 81 (2001), pp. 1033--1039
  23. White, J. E., et al., Biomass pyrolysis kinetics: a comparative critical review with relevant agricultural residue case studies, Journal Analytical and Applied Pyrolysis, 91 (2011), pp. 1--33
  24. Wu, Z., et al., Thermochemical behavior and char morphology analysis of blended bituminous coal and lignocellulosic biomass model compound co--pyrolysis: Effects of cellulose and carboxymethylcellulose sodium, Fuel, 171 (2016), pp. 65--73
  25. Kantarelis, E., et al., Thermochemical treatment of E--waste from small household appliances using highly pre--heated nitrogen--thermogravimetric investigation and pyrolysis kinetics, Applied Energy, 88 (2011), pp. 922--929
  26. Niu, Z., et al., Investigation of mechanism and kinetics of non--isothermal low temperature pyrolysis of perhydrous bituminous coal by in--situ FTIR, Fuel, 172 (2016), pp. 1--10
  27. Fei, Y,. et al., Comparison of some physico--chemical properties of Victorian lignite dewatered under non--evaporative conditions, Fuel, 84 (2006), pp. 1987--1991
  28. Qiu, P., et al., Effects of alkali and alkaline earth metallic species on pyrolysis characteristics and kinetics of zhundong coal, Journal of Fuel Chemistry and Technology, 42 (2014), pp. 1178--1189
  29. Barriocanal, C., et al., On the relationship between coal plasticity and thermogravimetric analysis, Journal Analytical and Applied Pyrolysis, 67 (2003), pp. 23--40
  30. Damartzis, T. H., et al., Thermal degradation studies and kinetic modeling of cardoon (Cynara cardunculus) pyrolysis using thermogravimetric analysis (TGA), Bioresource Technology, 102 (2011), pp. 6230--6238
  31. Gavalas, G. R., Coal pyrolysis, Elsevier Scientific Publishing Company, New York, USA, 1982
  32. Svabova, M., et al., Water vapour adsorption on coal, Fuel, 90 (2011), pp. 1892--1899
  33. Solomon, P. R., Hamblen, D. G., Finding order in coal pyrolysis kinetic, Progress in Energy Combustion Science, 9 (1983), pp. 323--361
  34. Solomon, P. R., et al., Coal pyrolysis:experiments, kinetic rates and mechanisms, Progress in Energy Combustion Science, 18 (1992), pp. 133--220
  35. Khare, P., et al., Application of chemometrics to study the kinetics of coal pyrolysis: a novel approach, Fuel, 90 (2011), pp. 3299--3305
  36. Wu, D., et al., Investigation on structural and thermodynamic characteristics of perhydrous bituminous coal by Fourier transform infrared spectroscopy and thermogravimetry/mass spectrometry, Energy Fuels, 28 (2014), pp. 3024--3035