Prediction of Ash Deposition in Pulverised Coal Combustion Systems

  • Francis C. C. Lee
  • Gerry S. Riley
  • Fred C. Lockwood


A predictive scheme based on CCSEM flyash data and Computational Fluid Dynamics (CFD) has been developed to study the slagging propensity of coals. The model has been applied to predict the deposition potential of three UK coals; Bentinck, Daw Mill and Silverdale, in a pilot scale single burner ash deposition test facility and an utility size multi-burner front wall-fired furnace. The project is part of a collaborative research programme sponsored by the UK Department of Trade and Industry and involved various industrial organisations and universities. The objective of the project is to understand the fundamental aspects of slagging in pulverised coal-fired combustion systems. This paper is a sequel to the poster paper entitled: The Prediction of Ash Deposition in a Coal Fired Axi-symmetric Furnace, presented in the last Engineering Foundation Conference [Lee et al, 1993]. The present model predicts the relative slagging propensity of the three coals correctly. The predicted deposition patterns are also consistent with the observations. The results from the model indicate a preferential deposition of iron dunng the initial stage of ash deposition. The average compositions of the deposits become closer to that of the bulk ash when the accumulation of ash deposits is taken into account.


Computational Fluid Dynamics Arrival Rate Injection Point Rear Wall Wall Deposit 
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Copyright information

© Springer Science+Business Media New York 1996

Authors and Affiliations

  • Francis C. C. Lee
    • 1
  • Gerry S. Riley
    • 1
  • Fred C. Lockwood
    • 2
  1. 1.Windmill Hill Business ParkNational Power PLCSwindonUK
  2. 2.Technology and Medicine, Department of Mechanical Eng.Imperial College of ScienceLondonUK

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