THERMAL SCIENCE

International Scientific Journal

Xin Yang

,

Zhanwei Liang

,

Hongwei Chen

,

Jixuan Wang

,

Xinglong Mu

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

ABSTRACT
The CO2 gasification of South Open-pit Mines coal from Zhundong field of China using Ca(OH)2 or K2CO3 as catalyst with different loading methods and contents were conducted in thermogravimetric analysis. Comparison of the gasification reactivity and rate of coal loaded various concentration of Ca(OH)2 concluded that the increase of Ca(OH)2 loading pronouncedly improved the reactivity and rate for grinding method, nevertheless, for impregnation and high pressure method the increase of Ca(OH)2 loading observed a similar catalytic effect on char gasification. However, the catalytic effect of K2CO3 revealed that the catalytic activity increased with the increase of K2CO3 loading for three loading method. For the same catalyst loading, the highest catalytic gasification reactivity achieved for Ca(OH)2 and K2CO3 were the loading methods of high pressure and grinding, respectively. In addition, the gasification of raw char, K2CO3 loaded char and Ca(OH)2 loaded char were quantitatively evaluated by kinetic analysis using shrinking core, random pore and modified random pore models.
KEYWORDS
CO2 gasification, catalytic effect, kinetic model, alkali metal, alkaline earth metal
PAPER SUBMITTED: 2020-08-11
PAPER REVISED: 2020-09-19
PAPER ACCEPTED: 2020-09-22
PUBLISHED ONLINE: 2020-10-10
DOI REFERENCE: https://doi.org/10.2298/TSCI200811305Y
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2022, VOLUME 26, ISSUE Issue 1, PAGES [119 - 133]
REFERENCES
  1. Roberts, D., Harris, D., Char gasification in mixture of CO 2 and H 2 O: competition and inhibition, Fuel, 86 (2007), pp. 2672-2678
  2. Tremel, A., et al., Experimental investigation of high temperature and high pressure coal gasification, Applied Energy, 92 (2012), pp . 279-285
  3. Prabowo, B., et al., CO 2 - steam mixture for direct and indirect gasification of rice straw in a downdraft gasifier: laboratory - scale experiments and performance prediction, Applied Energy, 113 (2014), pp . 670-679
  4. Wen, C., et a l., The pyrolysis and gasification performances of waste textile under carbon dioxide atmosphere, Journal of Thermal Analysis and Calorimetry, 128 (20 1 7), pp . 581-591
  5. Yang, Z., et al., Identification for the behavior of maximum reaction rate during the initial stage of coal char gasification, Journal of Thermal Analysis and Calorimetry, 128 (2017), pp . 1186-1194
  6. Grigore, M., et al., Mineral reactions during coal gasification with carbon dioxide, International Journal of Coal Geology, 75 ( 2008 ), pp . 213-224
  7. Zhang, F., et al., CO 2 gasification of Powder River Basin coal catalyzed by a cost - effective and environmentally friendly iron catalyst, Applied Energy, 145 (2015), pp . 295-305
  8. Salatino, P ., et al., Assessment of thermodeactivation during gasification of a bituminous coal char, Energy F uels, 13 (1999), pp . 1154-1159
  9. Ochoa, J., et al., CO 2 gasification of Argentinean coal chars: a kinetic characterization, Fuel Processing Technology, 74 (2001), pp . 161-171
  10. Fouga, G., et al., Kinetic study of Argentinean asphaltite gasification using carbon dioxide as gasifying agent, Fuel, 90 (2011), pp . 674-680
  11. Liu, Z ., Wang, Q., Kinetic study on metallurgical coke gasification by steam under various pressure, Journal of Thermal Analysis and Calorimetry, 129 (2017), pp: 1839-1845
  12. Fernandez, L., et al., Kinetic study of the CO 2 gasification of manure samples, Journal of Thermal Analysis and Calorimetry, 129 (2017), pp . 2499-2509
  13. Xu, S., et al., Effects of alkaline metal on coal gasification at pyrolysis and gasification phases, Fuel, 90 (2011), pp . 1723-1730
  14. Ding, L., et al., Catalytic effects of Na 2 CO 3 additive on coal pyrolysis and gasification, Fuel, 142 ( 2015 ), pp . 1 34-1 44
  15. Popa, T., et al., Catalytic gasification of a Powder River Basin coal, Fuel, 103 (2013), pp . 161-170
  16. Wang, J., et al., Enhanced catalysis of K 2 CO 3 for steam gasification of coal char by using Ca(OH) 2 in char preparation, Fuel, 89 (2010), pp. 310-317
  17. Kopyscinski, J., et al., K 2 CO 3 catalyzed CO 2 gasification of ash - free coal. Interactions of the catalyst with carbon in N 2 and CO 2 atmosphere, Fuel, 117 (2014), pp . 1181-1189
  18. Li, S., Cheng, Y., Catalytic gasification of gas - coal char in CO 2, Fuel, 74 (1995), pp. 456-458
  19. Popa, T ., et al., H 2 and COx generation from coal gasification catalyzed by a cost - effective iron catalyst, Applied Catalysis A, General, 464-465 (2013), pp . 207-217
  20. Ahmed, I., Gupta, A., K inetics of woodchips char gasification with steam and carbon dioxide, Applied Energy, 88 (2011), pp . 1613-1619
  21. Reyes, S ., Jensen, K ., Modeling of catalytic char gasification . Industrial and Engineering Chemistry Research Fundamentals, 23 (1984), pp . 223-229.
  22. Zolin, A., et al., A comparison of coal char reactivity determined from thermogravimetric and laminar flow reactor experiments, Energy Fuel s, 12 (1998), pp . 268-276
  23. Hayashi, J., et al., Roles of inherent metallic species in secondary reactions of tar and char during rapid pyrolysis of brown coals in a drop tube reactor, Fuel, 81 (2002), pp . 1977-1987
  24. Wang, Y ., et al., Investigation into the characteristics of Na 2 CO 3 - catalyzed steam gasification for a high - aluminum coal char, Journal of Thermal Analysis and Calorimetry, 131 (2018), pp . 1213-1220
  25. Marquez, M., et al., CO 2 and steam gasification of a grapefruit skin char, Fuel, 81 (2002), pp . 423-429
  26. Moulijn, J ., Kapteijn, F ., Towards a unified theory of reaction of carbon with oxygen - containing molecules, Carbon, 33 ( 1995 ), 8, pp . 1155-1165
  27. Wigmans, T ., et al., The influence of pretreatment conditions on the activity and stability of sodium and potassium catalysts in carbon - steam reactions, Carbon, 21 ( 1995 ), 3, pp . 295-301
  28. Bhatia, S., Perlmutter, D., A random pore model for fluid - solid reaction. 1. Isothermal, kinetic control, AIChE Journal, 26 ( 1980 ), 3, pp . 379-386
  29. Zhang, Y ., et al., Proposal of a semi - empirical kinetic model to reconcile with gasification reactivity profiles of biomass chars, Fuel, 87 ( 2008 ), pp . 475-481
  30. Zhang, Y ., et al., Modeling of catalytic gasification kinetics of coal char and carbon, Fuel, 89 ( 2010 ), pp . 152-157
  31. Homma, S ., et al., Gas - solid reaction model for a shrinking spherical particle with unreacted shrinking core, Chemical Engineering Science, 60 (2005), pp . 4971-4980
  32. Zhang, L ., et al., Gasification reactivity and kinetics of typical Chinese anthracite chars with steam and CO 2, Energy Fuels, 20 (2006), pp . 1201-1210
  33. Flynn, J., Thermal analysis kinetics - problems, pitfalls and how to deal with them, Journal of Thermal Analysis, 34 (1988), pp . 367-381
  34. Demicco, G ., et al., Kinetics of the gasification of a Rio Turbio coal under different pyrolysis temperatures, Fuel, 95 (2012), pp. 537-543.
  35. Gomez, A ., Mahinpey, N., Kinetic study of coal steam and CO 2 gasification: A new method to reduce interparticle diffusion, Fuel, 148 (2015), pp . 160-167
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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

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