Fast pyrolysis of coals under N2 and CO2 atmospheres

Experiments and modeling
  • Sami Zellagui
  • Cornelius Schönnenbeck
  • Nabila Zouaoui
  • Jean-François Brilhac
  • Olivier Authier
  • Emmanuel Thunin
  • Lynda Porcheron
Article
  • 15 Downloads

Abstract

Oxyfuel combustion represents one way for cleaner energy production using coal as combustible. The comparison between the oxycombustion and the conventional air combustion process starts with the investigation of the pyrolysis step. The aim of this contribution is to evaluate the impact of N2 (for conventional air combustion) and CO2 (for oxy-fuel combustion) atmospheres during pyrolysis of three different coals. The experiments are conducted in a drop tube furnace over a wide temperature range 800–1400 °C and for residence time ranging between 0.2 and 1.2 s. Coal devolatilized in N2 and CO2 atmospheres at low temperatures (< 1200 °C) provides similar results regarding mass loss, char combustion in thermogravimetric analysis and CO concentration. At higher temperatures (> 1200 °C) and longer residence times (> 0.5 s), the char-CO2 reaction is clearly observed, whose intensity depends on the nature of the coal. Furthermore, the volatile yields are simulated using Kobayashi’s scheme and kinetic parameters are predicted for each coal. The char gasification under CO2 is also accounted for by the model.

Keywords

Coal N2-devolatilization CO2-devolatilization Drop tube furnace Kinetic modeling Kobayashi’s scheme 

References

  1. 1.
    Du R, Wu K, Zhang L, Xu D, Chao C, Zhang B. A sectioning method for the kinetics study on anthracite pulverized coal combustion. J Therm Anal Calorim. 2017;130(3):2293–9.CrossRefGoogle Scholar
  2. 2.
    CO2 Emissions From Fuel Combustion Highlights. CO2 emissions from fuel combustion highlights. 2015. [cited 2016 Mar 21]. Available from: http://www.iea.org/publications/freepublications/publication/CO2EmissionsFromFuelCombustionHighlights2015.pdf.
  3. 3.
    Fujimori T, Yamada T. Realization of oxyfuel combustion for near zero emission power generation. Proc Combust Inst. 2013;34(2):2111–30.CrossRefGoogle Scholar
  4. 4.
    Singh D, Croiset E, Douglas PL, Douglas MA. Techno-economic study of CO2 capture from an existing coal-fired power plant: MEA scrubbing vs. O2/CO2 recycle combustion. Energy Convers Manag. 2003;44(19):3073–91.CrossRefGoogle Scholar
  5. 5.
    Cormos C-C. Oxy-combustion of coal, lignite and biomass: a techno-economic analysis for a large scale Carbon Capture and Storage (CCS) project in Romania. Fuel. 2016;169:50–7.CrossRefGoogle Scholar
  6. 6.
    Buhre BJP, Elliott LK, Sheng CD, Gupta RP, Wall TF. Oxy-fuel combustion technology for coal-fired power generation. Prog Energy Combust Sci. 2005;31(4):283–307.CrossRefGoogle Scholar
  7. 7.
    Bejarano PA, Levendis YA. Single-coal-particle combustion in O2/N2 and O2/CO2 environments. Combust Flame. 2008;153(1–2):270–87.CrossRefGoogle Scholar
  8. 8.
    Li Q, Zhao C, Chen X, Wu W, Lin B. Properties of char particles obtained under O2/N2 and O2/CO2 combustion environments. Chem Eng Process Process Intensif. 2010;49(5):449–59.CrossRefGoogle Scholar
  9. 9.
    Qiao Y, Zhang L, Binner E, Xu M, Li C-Z. An investigation of the causes of the difference in coal particle ignition temperature between combustion in air and in O2/CO2. Fuel. 2010;89(11):3381–7.CrossRefGoogle Scholar
  10. 10.
    Rathnam RK, Elliott LK, Wall TF, Liu Y, Moghtaderi B. Differences in reactivity of pulverised coal in air (O2/N2) and oxy-fuel (O2/CO2) conditions. Fuel Process Technol. 2009;90(6):797–802.CrossRefGoogle Scholar
  11. 11.
    Heuer S, Senneca O, Wütscher A, Düdder H, Schiemann M, Muhler M, et al. Effects of oxy-fuel conditions on the products of pyrolysis in a drop tube reactor. Fuel Process Technol. 2016;150:41–9.CrossRefGoogle Scholar
  12. 12.
    Tomaszewicz M, Tomaszewicz G, Sciazko M. Experimental study on kinetics of coal char-CO2 reaction by means of pressurized thermogravimetric analysis. J Therm Anal Calorim. 2017;130(3):2315–30.CrossRefGoogle Scholar
  13. 13.
    Solomon PR, Fletcher TH, Pugmire RJ. Progress in coal pyrolysis. Fuel. 1993;72(5):587–97.CrossRefGoogle Scholar
  14. 14.
    Solomon PR, Fletcher TH. Impact of coal pyrolysis on combustion. Symp Int Combust. 1994;25(1):463–74.CrossRefGoogle Scholar
  15. 15.
    Steer JM, Marsh R, Greenslade M, Robinson A. Opportunities to improve the utilisation of granulated coals for blast furnace injection. Fuel. 2015;151:40–9.CrossRefGoogle Scholar
  16. 16.
    Li X, Rathnam RK, Yu J, Wang Q, Wall T, Meesri C. Pyrolysis and combustion characteristics of an Indonesian low-rank coal under O2/N2 and O2/CO2 conditions. Energy Fuels. 2010;24(1):160–4.CrossRefGoogle Scholar
  17. 17.
    Gil MV, Riaza J, Álvarez L, Pevida C, Pis JJ, Rubiera F. Oxy-fuel combustion kinetics and morphology of coal chars obtained in N2 and CO2 atmospheres in an entrained flow reactor. Appl Energy. 2012;91(1):67–74.CrossRefGoogle Scholar
  18. 18.
    Molina A, Shaddix CR. Ignition and devolatilization of pulverized bituminous coal particles during oxygen/carbon dioxide coal combustion. Proc Combust Inst. 2007;31(2):1905–12.CrossRefGoogle Scholar
  19. 19.
    Shaddix CR, Molina A. Particle imaging of ignition and devolatilization of pulverized coal during oxy-fuel combustion. Proc Combust Inst. 2009;32(2):2091–8.CrossRefGoogle Scholar
  20. 20.
    Chang Q, Gao R, Li H, Dai Z, Yu G, Liu X, et al. Effects of CO2 on coal rapid pyrolysis behavior and chemical structure evolution. J Anal Appl Pyrolysis. 2017;128:370–8.CrossRefGoogle Scholar
  21. 21.
    Brix J, Jensen PA, Jensen AD. Coal devolatilization and char conversion under suspension fired conditions in O2/N2 and O2/CO2 atmospheres. Fuel. 2010;89(11):3373–80.CrossRefGoogle Scholar
  22. 22.
    Borrego AG, Alvarez D. Comparison of chars obtained under oxy-fuel and conventional pulverized coal combustion atmospheres. Energy Fuels. 2007;21(6):3171–9.CrossRefGoogle Scholar
  23. 23.
    Zhao H, Cao Y, Orndorff W. Gasification characteristics of coal char under CO2 atmosphere. J Therm Anal Calorim. 2014;116:1267–72.CrossRefGoogle Scholar
  24. 24.
    Zhang X, Liu Y, Wang C, Che D. Experimental study on interaction and kinetic characteristics during combustion of blended coal. J Therm Anal Calorim. 2012;107:935–42.CrossRefGoogle Scholar
  25. 25.
    Relcom—Reliable Combustion. [cited 2016 Jun 30]. Available from: http://www.relcomeu.com/.
  26. 26.
    Kobayashi H. Devolatilization of pulverized coal at high temperatures. Thesis, Massachusetts Institute of Technology; 1976 [cited 2016 Jun 13]. Available from: http://dspace.mit.edu/handle/1721.1/26754.
  27. 27.
    Relcom—Reliable Combustion—Fuels. [cited 2016 Jun 30]. Available from: http://www.relcomeu.com/projects_fuels.php.
  28. 28.
    Zellagui S, Schönnenbeck C, Zouaoui-Mahzoul N, Leyssens G, Authier O, Thunin E, et al. Pyrolysis of coal and woody biomass under N2 and CO2 atmospheres using a drop tube furnace—experimental study and kinetic modeling. Fuel Process Technol. 2016;148:99–109.CrossRefGoogle Scholar
  29. 29.
    Zellagui S, Trouvé G, Schönnenbeck C, Zouaoui-Mahzoul N, Brilhac J-F. Parametric study on the particulate matter emissions during solid fuel combustion in a drop tube furnace. Fuel. 2017;189:358–68.CrossRefGoogle Scholar
  30. 30.
    Naredi P, Pisupati S. Effect of CO2 during coal pyrolysis and char burnout in oxy-coal combustion. Energy Fuels. 2011;25(6):2452–9.CrossRefGoogle Scholar
  31. 31.
    Zanzi R, Sjöström K, Björnbom E. Rapid high-temperature pyrolysis of biomass in a free-fall reactor. Fuel. 1996;75(5):545–50.CrossRefGoogle Scholar
  32. 32.
    Thommes M, Kaneko K, Neimark AV, Olivier JP, Rodriguez-Reinoso F, Rouquerol J, et al. Physisorption of gases, with special reference to the evaluation of surface area and pore size distribution (IUPAC Technical Report). Pure Appl Chem. 2015;87(9–10):1051–69.Google Scholar
  33. 33.
    Du S-W, Chen W-H, Lucas JA. Pulverized coal burnout in blast furnace simulated by a drop tube furnace. Energy. 2010;35(2):576–81.CrossRefGoogle Scholar
  34. 34.
    Smoot LD, Smith PJ. Coal combustion and gasification. New York: Plenum Press; 1985.CrossRefGoogle Scholar
  35. 35.
    Idris SS, Rahman NA, Ismail K, Alias AB, Rashid ZA, Aris MJ. Investigation on thermochemical behaviour of low rank Malaysian coal, oil palm biomass and their blends during pyrolysis via thermogravimetric analysis (TGA). Bioresour Technol. 2010;101(12):4584–92.CrossRefGoogle Scholar
  36. 36.
    Morgan ME, Dekker JSA. Characterisation of the combustion performance of a suite of pulverised coals: report on the CC 1 trials. IJmuiden: International Energy Agency, International Flame Research Foundation; 1988.Google Scholar
  37. 37.
    Authier O, Thunin E, Plion P, Schönnenbeck C, Leyssens G, Brilhac J-F, et al. Kinetic study of pulverized coal devolatilization for boiler CFD modeling. Fuel. 2014;122:254–60.CrossRefGoogle Scholar
  38. 38.
    Everson RC, Neomagus HWJP, Kaitano R, Falcon R, du Cann VM. Properties of high ash coal-char particles derived from inertinite-rich coal: II. Gasification kinetics with carbon dioxide. Fuel. 2008;87(15–16):3403–8.CrossRefGoogle Scholar
  39. 39.
    Wang G, Zhang J, Hou X, Shao J, Geng W. Study on CO2 gasification properties and kinetics of biomass chars and anthracite char. Bioresour Technol. 2015;177:66–73.CrossRefGoogle Scholar
  40. 40.
    Tomaszewicz M, Labojko G, Tomaszewicz G, Kotyczka-Moranska M. The kinetics of CO2 gasification of coal char. J Therm Anal Calorim. 2013;113:1327–35.CrossRefGoogle Scholar

Copyright information

© Akadémiai Kiadó, Budapest, Hungary 2018

Authors and Affiliations

  1. 1.LGRE EA 2334Université de Haute-AlsaceMulhouseFrance
  2. 2.Fluid Dynamics Power Generation and EnvironmentEDF R&DChatouFrance

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