Simulation and Experimental Study of Water Soot Blower for Pulverized-Coal Boiler Based on Discrete Phase Model

Abstract:

A pulverized-coal boiler is a type of boiler that is commonly seen in power plants. During an operation, a portion of the coal is converted to ash. The consequence is a cause of slagging on the furnace wall and a considerable loss in heat transfer performance. In coal-fired power plants, slagging is one of the most common causes of maintenance issues. This problem can be resolved by using a water soot blower cleaning system. It shoots a high-pressure jet of water through a hole in the side of the furnace’s wall to clean the opposite wall surfaces. This study presents a Computational Fluid Dynamics (CFD) investigation of the water soot blower trajectory with a flow field in full-scale boiler. Multiphase-flow simulation is utilized. The turbulence model couple and Discrete Phase Model are used to analyze flow field in boiler and water soot blower trajectory, respectively. The aim is to accurately determine an injection angle degree for the water soot blower. The CFD results are compared with the experiment of water soot blower shooting in Cold Air Velocity Test (CAVT) conditions. The results of the study show that the simulation results agree with the experimental data. Moreover, the velocity profile of numerical study shows that the effect of flow field in boiler has little effect on the water soot blower trajectory.

• Periodical: Solid State Phenomena (Volume 349)
• Pages: 109-116
• DOI: https://doi.org/10.4028/p-Ce1M9K
• Online since: September 2023
• Authors: Teewin Plangsrinont*, Wasawat Nakkiew, Adirek Baisukhan, Sasithorn Khamput
• Keywords: Computational Fluid Dynamics, Discrete Phase Model, Multiphase-Flow, Pulverized-Coal Boiler, Tangentially Fired Boiler

References

[1] D. Tian, L. Zhong, P. Tan, L. Ma, Q. Fang, C. Zhang, D. Zhang, and G. Chen, "Influence of vertical burner tilt angle on the gas temperature deviation in a 700 MW low no X tangentially fired pulverised-coal boiler," Fuel Processing Technology, vol. 138, p.616–628, 2015.

DOI: 10.1016/j.fuproc.2015.07.002

[2] G. O'Brien, B. Firth, and B. Adair, "The application of the Coal Grain Analysis Method to coal liberation studies," International Journal of Coal Preparation and Utilization, vol. 31, no. 2, p.96–111, 2011.

DOI: 10.1080/19392699.2010.537995

[3] B. G. Miller, Clean coal engineering technology, Elsevier, 2010.

[4] B. Akkinepally, J. Shim, and K. Yoo, "Numerical and experimental study on biased tube temperature problem in tangential firing boiler," Applied Thermal Engineering, vol. 126, p.92–99, 2017.

DOI: 10.1016/j.applthermaleng.2017.07.121

[5] H. Bilirgen, "Slagging in PC boilers and developing mitigation strategies," Fuel, vol. 115, p.618–624, 2014.

DOI: 10.1016/j.fuel.2013.07.034

[6] X. Wang, Z. Xu, B. Wei, L. Zhang, H. Tan, T. Yang, H. Mikulčić, and N. Duić, "The ash deposition mechanism in boilers burning Zhundong coal with high contents of sodium and calcium: A study from ash evaporating to condensing," Applied Thermal Engineering, vol. 80, p.150–159, 2015.

DOI: 10.1016/j.applthermaleng.2015.01.051

[7] Z. Yuan, Z. Chen, B. Zhang, X. Gao, J. Li, Y. Qiao, and Z. Li, "Study on the slagging trends of the pre-combustion chamber in industrial pulverized coal boiler under different excess air coefficients by CFD Numerical Simulation," Energy, vol. 264, p.126184, 2023.

DOI: 10.1016/j.energy.2022.126184

[8] J. P. Hurley, S. A. Benson, and A. K. Mehta, "Ash deposition at low temperatures in boilers burning high-calcium coals," The Impact of Ash Deposition on Coal Fired Plants, p.19–30, 2022.

DOI: 10.1201/9780203736616-3

[9] L. Xu, Y. Huang, J. Yue, L. Dong, L. Liu, J. Zha, M. Yu, B. Chen, Z. Zhu, and H. Liu, "Improvement of slagging monitoring and soot-blowing of waterwall in a 650mwe coal-fired utility boiler," Journal of the Energy Institute, vol. 96, p.106–120, 2021.

DOI: 10.1016/j.joei.2021.02.006

[10] P. Pintana, N. Tippayawong, A. Nuntaphun, and P. Thongchiew, "Characterization of slag from combustion of pulverized lignite with high calcium content in utility boiler," Energy Exploration & Exploitation, vol. 32, no. 3, p.471–482, 2014.

DOI: 10.1260/0144-5987.32.3.471

[11] H. Park, J. Lee, J. Lim, H. Cho, and J. Kim, "Optimal operating strategy of ash deposit removal system to maximize boiler efficiency using CFD and a thermal transfer efficiency model," Journal of Industrial and Engineering Chemistry, vol. 110, p.301–317, 2022.

DOI: 10.1016/j.jiec.2022.03.004

[12] S. V. Syrodoy, G. V. Kuznetsov, N. Y. Gutareva, and V. V. Salomatov, "The efficiency of heat transfer through the ash deposits on the heat exchange surfaces by burning coal and coal-water fuels," Journal of the Energy Institute, vol. 91, no. 6, p.1091–1101, 2018.

DOI: 10.1016/j.joei.2017.06.014

[13] T. Plangsrinont and W. Nakkiew, " Computational Fluid Dynamics Study on Water Soot Blower Direction in Tangentially Fired Pulverized-Coal Boiler," International Journal of Energy and Power Engineering, vol. 15, no. 8, p.318–324, 2021.

[14] Hirt, C. W., & Nichols, B. D. (1981). Volume of fluid (VOF) method for the dynamics of free boundaries. Journal of computational physics, 39(1), 201-225.

DOI: 10.1016/0021-9991(81)90145-5

[15] A. Frohn and N. Roth, "Dynamics of droplets," 2000.

[16] S. Chadha, R. Jefferson-Loveday, and T. Hussain, "A high-fidelity simulation of the primary breakup within Suspension High Velocity Oxy fuel thermal spray using a coupled volume of fluid and discrete phase model," International Journal of Multiphase Flow, vol. 133, p.103445, 2020.

DOI: 10.1016/j.ijmultiphaseflow.2020.103445

[17] J. LIU and P. KE, "Modelling and analysis of initial icing roughness with fixed-grid enthalpy method based on DPM-VOF algorithm," Chinese Journal of Aeronautics, vol. 35, no. 7, p.168–178, 202

DOI: 10.1016/j.cja.2021.07.028