Effect of H2O on Preheating Combustion Characteristics in O2/CO2 and O2/N2 Atmospheres

Expand
  • 1. Institute of Engineering Thermophysics, Chinese Academy of Sciences, Beijing 100190, China
    2. University of Chinese Academy of Sciences, Beijing 100049, China

Online published: 2023-11-26

Supported by

This study is supported by the National Natural Science Foundation of China (No. 51676187).

Copyright

Science Press, Institute of Engineering Thermophysics, CAS and Springer-Verlag GmbH Germany, part of Springer Nature 2023

Abstract

This study explores the effect of H2O on the characteristics of the oxy-fuel combustion process preheated by a circulating fluidized bed. The preheating and combustion characteristics have been studied in O2/CO2/H2O and O2/N2/H2O atmospheres. It was observed that the preheating temperature decreased with adding steam. Meanwhile, the addition of steam enhanced the C-H2O gasification reaction, while weakened the C-CO2 gasification reaction. As a result, the H2 concentration was increased, while the CO concentration was reduced. H2O was conducive towards increasing the surface area and pore formation of the preheated char, though it had an insignificant effect on the particle size. Moreover, H2O enhanced the preheated char activity, which was helpful for ignition and stable combustion. The NOx emission was observed to increase from 68 to 79 mg/MJ and 62 to 81 mg/MJ in O2/CO2 and O2/N2 atmospheres, respectively, after adding steam.

Cite this article

PAN Fei, ZHU Jianguo, LIU Jingzhang, LIU Yuhua . Effect of H2O on Preheating Combustion Characteristics in O2/CO2 and O2/N2 Atmospheres[J]. Journal of Thermal Science, 2023 , 32(6) : 2235 -2242 . DOI: 10.1007/s11630-023-1851-6

References

[1] Scheffknecht G., Al-Makhadmeh L., Schnell U., et al., Oxy-fuel coal combustion—A review of the current state-of-the-art. International Journal of Greenhouse Gas Control, 2011, 5: S16–S35.
[2] Boot-Handford M.E., Abanades J.C., Anthony E.J., et al., Carbon capture and storage update. Energy & Environmental Science, 2014, 7(1): 130–189.
[3] Yin C., Yan J., Oxy-fuel combustion of pulverized fuels: Combustion fundamentals and modeling. Applied Energy, 2016, 162: 742–762. 
[4] Dillon D.J., Panesar R.S., Wall R.A., et al., Oxy-combustion processes for CO2 capture from advanced supercritical PF and NGCC power plant. Greenhouse Gas Control Technologies, 2005, pp. 211–220. DOI: 10.1016/B978-008044704-9/50022-7
[5] Chen L., Yong S.Z., Ghoniem A.F., Oxy-fuel combustion of pulverized coal: Characterization, fundamentals, stabilization and CFD modeling. Progress in Energy & Combustion Science, 2012, 38(2): 156–214. 
[6] Yi B., Zhang L., Huang F., et al., Effect of H2O on the combustion characteristics of pulverized coal in O2/CO2 atmosphere. Applied Energy, 2014, 132: 349–357.
[7] Kakaras E., Koumanakos A., Doukelis A., et al., Oxyfuel boiler design in a lignite-fired power plant. Fuel, 2007, 86(14): 2144–2150.
[8] Duan L., Sun H., Zhao C., et al., Coal combustion characteristics on an oxy-fuel circulating fluidized bed combustor with warm flue gas recycle. Fuel, 2014, 127: 47–51.
[9] Zou C., Zhang L., Cao S., et al., A study of combustion characteristics of pulverized coal in O2/H2O atmosphere. Fuel, 2014, 115: 312–320.
[10] Zhou H., Li Y., Li N., et al., Experimental investigation of ignition and combustion characteristics of single coal and biomass particles in O2/N2 and O2/H2O. Journal of the Energy Institute, 2019, 92(3): 502–511.
[11] Xu J., Su S., Sun Z., et al., Effects of steam and CO2 on the characteristics of chars during devolatilization in oxy-steam combustion process. Applied Energy, 2016, 182: 20–28.
[12] Riaza J., Álvarez L., Gil M V., et al., Effect of oxy-fuel combustion with steam addition on coal ignition and burnout in an entrained flow reactor. Energy, 2011, 36(8): 5314–5319. 
[13] Toftegaard M.B., Brix J., Jensen P.A., et al., Oxy-fuel combustion of solid fuels. Progress in Energy and Combustion Science, 2010, 36(5): 581–625.
[14] Hecht E.S., Shaddix C.R., Geier M., et al., Effect of CO2 and steam gasification reactions on the oxy-combustion of pulverized coal char. Combustion and Flame, 2012, 159(11): 3437–3447.
[15] Zhang Z., Lu B., Zhao Z., et al., CFD modeling on char surface reaction behavior of pulverized coal MILD-oxy combustion: Effects of oxygen and steam. Fuel Processing Technology, 2020, 204: 106405.
[16] Sekine Y., Ishikawa K., Kikuchi E., et al., Reactivity and structural change of coal char during steam gasification. Fuel, 2006, 85(2): 122–126.
[17] Yi B., Zhang L., Yuan Q., et al., The evolution of coal char structure under the oxy-fuel combustion containing high H2O. Fuel Processing Technology, 2016, 152: 294–302.
[18] Tian F.J., Yu J., McKenzie L.J., et al., Conversion of fuel-N into HCN and NH3 during the pyrolysis and gasification in steam: A comparative study of coal and biomass. Energy & Fuels, 2007, 21(2): 517–521.
[19] Park D.C., Day S.J., Nelson P.F., Nitrogen release during reaction of coal char with O2, CO2, and H2O. Proceedings of the Combustion Institute, 2005, 30(2): 2169–2175.
[20] Zhu C., Liu S., Liu H., et al., NOx emission characteristics of fluidized bed combustion in atmospheres rich in oxygen and water vapor for high-nitrogen fuel. Fuel, 2015, 139: 346–355.
[21] Zhu J.G., Study on high temperature and low oxygen air combustion and nitrogen oxide formation characteristics of pulverized coal. University of Chinese Academy of Sciences, Beijing, China, 2008.
[22] Zhu J., Yao Y., Lu Q., et al., Experimental investigation of gasification and incineration characteristics of dried sewage sludge in a circulating fluidized bed. Fuel, 2015, 150: 441–447.
[23] Ouyang Z., Zhu J., Lu Q., Experimental study on preheating and combustion characteristics of pulverized anthracite coal. Fuel, 2013, 113: 122–127.
[24] Yao Y., Zhu J., Lu Q., Experimental study on nitrogen transformation in combustion of pulverized semi-coke preheated in a circulating fluidized bed. Energy & Fuels, 2015, 29(6): 3985–3991.
[25] Zhu J., Ouyang Z., Lu Q., An experimental study on NOx emissions in combustion of pulverized coal preheated in a circulating fluidized bed. Energy & Fuels, 2013, 27(12): 7724–7729.
[26] Zhu S., Zhu J., Lyu Q., et al., NO emissions under pulverized char combustion in O2/CO2/H2O preheated by a circulating fluidized bed. Fuel, 2019, 252: 512–521.
[27] Yi B., Zhang L., Yuan Q., Study of the flue gas characteristics and gasification reaction of pulverized coal combustion in O2/CO2/H2O atmosphere. Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2018, 40(13): 1565–1572.
[28] Xu J., Su S., Sun Z., et al., Effects of steam and CO2 on the characteristics of chars during devolatilization in oxy-steam combustion process. Applied Energy, 2016, 182: 20–28. 
[29] Sung Y., Moon C., Eom S., et al., Coal-particle size effects on NO reduction and burnout characteristics with air-staged combustion in a pulverized coal-fired furnace. Fuel, 2016, 182: 558–567.
[30] Sheng C., Char structure characterised by Raman spectroscopy and its correlations with combustion reactivity. Fuel, 2007, 86(15): 2316–2324.
[31] Sadezky A., Muckenhuber H., Grothe H., et al., Raman microspectroscopy of soot and related carbonaceous materials: Spectral analysis and structural information. Carbon, 2005, 43(8): 1731–1742.
[32] Liu X., Zheng Y., Liu Z., et al., Study on the evolution of the char structure during hydrogasification process using Raman spectroscopy. Fuel, 2015, 157: 97–106.
Outlines

/