Abstract
High speed camera is employed to capture the transient images of the burning particle in a flat-flame entrained flow reactor, some information of the burning particle, such as the optical intensity and the residence time, are obtained through analysis of transient images. The ignition and devolatilization behavior of different rank coals at 1,670, 1,770 and 1,940 K over a range of 2–30% O2 in both N2 and CO2 diluent gases are researched. The results indicate that the laws of ignition and devolatilization of pulverized coals in low oxygen O2/CO2 atmosphere are consistent with the literature, which focus on the environments of high oxygen contents (10–30%) or lower temperate (900–1,500 K). With the gas temperature and oxygen content increased, the ignition delay time and devolatilization time for the lower oxygen content cases decreased for both N2 and CO2 atmosphere. With the use CO2 in place of N2 in low oxygen content, the ignition delay was retarded and the duration of devolatilization was increased. The effect of CO2 on coal particle ignition is explained by its higher molar specific heat. And the effect of CO2 on devolatilization results from its effect on the diffusion rates of volatile fuel and oxygen.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
References
Faundez J, et al. Ignition behaviour of different rank coals in an entrained flow reactor. Fuel. 2005;84(17):2172–7.
Essenhigh RH, Misra MK, Shaw DW. Ignition of coal particles: a review. Combust Flame. 1989;77(1):3–30.
Annamalai K, Durbetaki P. A theory on transition of ignition phase of coal particles. Combust Flame. 1977;29:193–208.
Gururajan VS, et al. Mechanisms for the ignition of pulverized coal particles. Combust Flame. 1990;81(2):119–32.
Wall TF, et al. The ignition of coal particles. Fuel. 1991;70(9): 1011–6.
Wendt C, et al. A model for devolatilization and ignition of an axisymmetric coal particle. Proc Combust Inst. 2002;29(1):449–57.
Du X, Annamalai K. The transient ignition of isolated coal particle. Combust Flame. 1994;97(3–4):339–54.
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.
Chi T, et al. Investigations into the ignition behaviors of pulverized coals and coal blends in a drop tube furnace using flame monitoring techniques. Fuel. 2010;89(3):743–51.
McLean WJ, Hardesty DR, Pohl JH. Direct observations of devolatilizing pulverized coal particles in a combustion environment. Symp (Int) Combust. 1981;18(1):1239–48.
Seeker WR, et al. The thermal decomposition of pulverized coal particles. Symp (Int) Combust. 1981;18(1):1213–26.
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.
Zhang L, et al. In situ diagnostics of Victorian brown coal combustion in O2/N2 and O2/CO2 mixtures in drop-tube furnace. Fuel. 2010;89(10):2703–12.
Zhang L, et al. Experimental investigation of the combustion of bituminous coal in air and O2/CO2 mixtures: 1. Particle imaging of the combustion of coal and char. Energy Fuels. 2010;24(9): 4803–11.
Binner E, et al. In-situ observation of the combustion of air-dried and wet Victorian brown coal. Proc Combust Inst. 2011;33(2): 1739–46.
Shaddix CR. Correcting thermocouple measurements for radiation loss: a critical review, A.S.o.M.E. National Heat Transfer Conference NHTC’99 33rd, Editor, Albuquerque, NM, 1999. p. 1150.
Law CK. Combustion physics. Cambridge: Cambridge University Press; 2006. 309.
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.
Acknowledgments
This work was supported by the National Basic Research Program of China (Grant No. 2010CB227004) and the National Natural Science Foundation of China (Grant No. 50721005, 50976042, 51006043).
Author information
Authors and Affiliations
Corresponding author
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2013 Springer-Verlag Berlin Heidelberg & Tsinghua University Press
About this paper
Cite this paper
Huang, X., Li, J., Liu, Z., Yang, M., Wang, D., Zheng, C. (2013). Ignition and Devolatilization of Pulverized Coals in Lower Oxygen Content O2/CO2 Atmosphere. In: Qi, H., Zhao, B. (eds) Cleaner Combustion and Sustainable World. ISCC 2011. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-30445-3_16
Download citation
DOI: https://doi.org/10.1007/978-3-642-30445-3_16
Published:
Publisher Name: Springer, Berlin, Heidelberg
Print ISBN: 978-3-642-30444-6
Online ISBN: 978-3-642-30445-3
eBook Packages: EnergyEnergy (R0)