Combined operation mode of sub-critical W-flame boiler and coal mill optimized numerical simulation

Lun Ma, Qingyan Fang, Dengfeng Tian, Cheng Zhang, Gang Chen

Article ID: 1506
Vol 4, Issue 1, 2021

VIEWS - 589 (Abstract) 245 (pdf)

Abstract


The flow, combustion, heat transfer and NOx emission characteristics of a 600 MW subcritical W-flame boiler were numerically simulated under different combined operation modes of coal mills, and compared with the measured results. The results show that the combustion, average residence time, burnout rate, NOx emission characteristics and temperature distribution near the side wall of pulverized coal particles in the furnace have different effects on the combined operation mode of pulverized coal. In the combustion efficiency of give attention to two or more things, screen superheater section of fly ash carbon content and flue gas temperature of entrance at the same time, compared with six coal mill run at the same time, 5 coal mill run, shut down near the side wall of the coal mill is beneficial to reduce NOx emission concentration, to achieve the emission reduction, at the same time under the wing wall and side wall area chamber of a stove or furnace slagging significantly reduce.

Keywords


Subcritical W-Flame Boiler; Combustion Optimization; Combined Operation Mode of Coal Mill; NOx Emission Characteristics; Numerical Simulation

Full Text:

pdf


References


1. Kuang M, Li Z, Zhang Y, et al. Asymmetric combustion characteristics and NOx emissions of a down-fired 300 MWe utility boiler at different boiler loads. Energy 2012; 37(1): 580–590.

2. Guo Y. Numerical simulation and experimental study of low NOx combustion technology for ultrafine powder recombustion. Beijing: North China Electric Power University; 2006.

3. Zeng H. Study on large capacity boiler high efficiency low NOx combustion technology. Boiler Manufacturing 2001; (1): 1–11.

4. Li Z, Liu G, Zhu Q, et al. Combustion and NOx emission characteristics of a retrofitted down-fired 660 MWe utility boiler at different loads. Applied Energy 2011; 88(7): 2400–2406.

5. Fang Q, Wang H, Chen G, et al. Optimal simulation on the combination mode of mills for an ultra-supercritical utility boiler. Proceedings of the CSEE 2011; 31(5): 1–6.

6. Kuang M, Li Z, Zhu Q, et al. Arch-and wall-air distribution optimization for a down-fired 350 MWe utility boiler: A cold-modeling experimental study accompanied by real-furnace measurements. Applied Thermal Engineering 2013; 54(1): 226–236.

7. Miao C, Wang J. Analysis of asymmetric burning problem in a W-shaped flame boiler of 600 MW unit. Thermal Power Generation 2005; (12): 48–51.

8. Liu R, Hui S, Yu Z, et al. Effect of air distribution on aerodynamic field and coal combustion in an arch-fired furnace. Energy & Fuels 2010; 24(10): 5514–5523.

9. Kuang M, Li Z, Xu S, et al. Improving combustion characteristics and NOx emissions of a down-fired 350 MWe utility boiler with multiple injection and multiple staging. Environmental Science & Technology 2011; 45(8): 3803–3811.

10. Fang Q, Wang H, Wei Y, et al. Numerical simulations of the slagging characteristics in a down-fired pulverized-coal boiler furnace. Fuel Processing Technology 2010; 91(1): 88–96.

11. Kuang M, Li Z, Ling Z, et al. Impact of the over fire air location on combustion improvement and NOx abatement of a down-fired 350 MWe utility boiler with multiple injection and multiple staging. Energy & Fuels 2011; 25(10): 4322–4332.

12. Kuang M, Li Z, Ling Z, et al. Effect of over fire air angle on flow characteristics within a small-scale model for a deep-air-staging down-fired Furnace. Energy Conversion and Management 2014; 79(3): 367–376.

13. Li Z, Ren F, Liu G, et al. Combustion technologies of down-fired boilers with high efficiency and low-NOx emissions. Journal of Power Engineering 2010; 30(9): 645–651, 662.

14. Gao Z, Sun X, Song W, et al. Numerical simulation on the effect of structure on flame for W flame boiler. Proceedings of the CSEE 2009; 29(29): 13–18.

15. Smoot LD, Smith PJ. Coal combustion and gasification. New York, USA: Plenum Press; 1989.

16. Hill SC, Smoot LD. Modeling of nitrogen oxides formation and destruction in combustion systems. Progress in Energy and Combustion Science 2000; 26(4/5/6): 417–458.

17. De Soete GG. Overall reaction rates of NO and N2 formation from fuel nitrogen. 15th Symposium (International) on the Combustion. Pittsburgh, USA 1975; 15(1): 1093–1102.

18. Heng C, Moght Aderi B, Gupta R, et al. A computational fluid dynamics based study of the combustion characteristics of coal blends in pulverized coal-fired furnace. Fuel 2004; 83(11): 1543–1552.

19. Gera D, Mathur M, Freman M. Parametric sensitivity study of a CFD-based coal devolatilization model. Energy & Fuels 2003; 17(3): 794–795.

20. Li J, Wang Q, Li H, et al. The formation mechanism and control of NOx in low volatile matter pulverized coal combustion. Journal of Power Engineering 2005; 25(Sup): 12–17.

21. Cen K, Yao Q, Luo Z. High order combustion. Hangzhou: Zhejiang University Press; 2002.




DOI: https://doi.org/10.24294/tse.v4i1.1506

Refbacks

  • There are currently no refbacks.


Creative Commons License
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

Creative Commons License

This site is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.