International Scientific Journal


The influence of main operating parameters on boiler performance was studied, such as bed pressure drop, primary air-flow and secondary air-flow. Combustion adjustment tests were carried out on a circulating fluidized bed boiler with rated capacity of 240 t/h. From the test results, it can be seen that the loss due to exit flue gas is the largest heat loss of the boiler, accounting for more than 70% of the total heat losses. For coal fired boilers, compared with the loss due to unburned solids, the loss due to unburned gases is quite small. The unburned carbon con-tent in bottom ash is far lower than the value in fly ash. The trend of CO concentration in the exit flue gas is similar to that of the unburned carbon content in fly ash. To achieve higher boiler efficiency, the bed pressure drop is suggested to be maintained in about 8.5-9.0 kPa and the oxygen content in exit flue gas around 4%. The NOx emission concentration usually presents a negative correlation with CO concentration in exit flue gas. Through combustion adjustment and operation optimization, the NOx emission can be decreased by about 30% without affecting the boiler efficiency.
PAPER REVISED: 2019-11-28
PAPER ACCEPTED: 2019-12-10
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THERMAL SCIENCE YEAR 2020, VOLUME 24, ISSUE Issue 5, PAGES [2689 - 2698]
  1. Sung, Y., Choi, G., Effectiveness between swirl intensity and air staging on NOx emissions and burnout characteristics in a pulverized coal fired furnace, Fuel Processing Technology, 139 (2015), pp. 15-24
  2. Ma, Z. Z., et al., Characteristics of NOx emission from Chinese coal-fired power plants equipped with new technologies, Atmospheric Environment, 131 (2016), pp. 164-170
  3. Wang, X. B., et al., Effect of biomass/coal co-firing and air staging on NOx emission and combustion efficiency in a drop tube furnace, Energy Procedia, 61 (2014), pp. 2331-2334
  4. Li, S., et al., Optimization of coal reburning in a 1 MW tangentially fired furnace, Fuel, 86 (2007), pp. 1169-1175
  5. Li, S., et al. NOx emission and thermal efficiency of a 300 MWe utility boiler retrofitted by air staging, Applied Energy, 86 (2009), pp.1797-1803
  6. Zhou, W. T., et al., Combustion adjustment tests for preventing overheating problems in a 600 MW supercritical W-flame boiler, Journal of Chinese Society of Power Engineering, 33 (2013), pp. 753-758 (in Chinese)
  7. Wang, X. D., et al., Experimental study of the effect of boiler combustion control on NOx emission and boiler efficiency, Journal of Power Engineering, 28 (2008), pp. 19-23 (in Chinese)
  8. Xiao, H. P., et al., Effect of combustion adjustment on NOx emission and boiler efficiency, Proceedings of the CSEE, 31 (2011), pp. 1-6 (in Chinese)
  9. Zhong, L., et al., Test study on combustion adjustment of one boiler for 300 MW unit, Thermal Power Generation, 41 (2012), pp. 69-72, 76 (in Chinese)
  10. Qi, G. L., et al. Combustion adjustment test of circulating fluidized bed boiler, Applied Thermal Engineering, 124 (2017), pp. 1505-1511
  11. Wei, Z. B., et al. Optimization of operating parameters for low NOx emission in hightemperature air combustion, Energy & Fuels, 26 (2012), pp. 2821-2829
  12. ASME PTC4-2008. Fired Steam Generators Performance Test Code. New York: The American Society of Mechanical Engineers, 2008
  13. General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China. Performance Test Code for Utility Boiler: GB/T 10184-2015. Beijing: China Standards Press, 2016
  14. Liu, X. M., et al., Effect of furnace pressure drop on heat transfer in a 135 MW CFB boiler, Powder Technology, 284 (2015), pp. 19-24
  15. Xiao, X. B., et al., Research on carbon content in fly ash from circulating fluidized bed boilers, Energy & Fuels, 19 (2005), pp.1520-1525
  16. Yang, H. R., et al., Effect of bed pressure drop on performance of a CFB boiler, Energy & Fuels, 23 (2009), pp. 2886-2890
  17. Chen, J. H., et al., The effect of solid concentration on the secondary air-jetting penetration in a bubbling fluidized bed, Powder Technology, 185 (2008), pp. 164-169
  18. Liu, X. M., et al., Effect of flow-pattern reconstruction on combustion efficiency and pollutant emission in CFB boiler, International Conference on Energy, Ecology and Environment, Melbourne, 2018

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