Iron Oxidation State and Its Effect on Ash Particle Stickiness

  • L. E. BoolIII
  • J. J. Helble


The oxidation state of iron in glassy particles dramatically affects the deposition of those particles in pulverized coal fired utility boilers. In this work, two synthetic ashes were fabricated and used to explore the effect of iron oxidation state on ash stickiness in a bench scale experimental study. The iron in these synthetic ashes, approximately 20 wt%, was initially 100% in the Fe(II) state. Experiments conducted with these ashes in an electrically heated entrained flow reactor were used to determine the stickiness of the synthetic ashes under different oxidizing environments and temperatures. Particulate samples were collected to measure the conversion of Fe(II) to Fe(III) under various conditions, and the results used to determine the rate of iron oxidation in glassy ash particles. This information was used to identify the rate limiting step for iron oxidation and to develop a simple preliminary model to predict the fraction of Fe(II) oxidized to Fe(III) as a function of time.


Particle Temperature Collection Efficiency Oxygen Solubility Adhesion Efficiency Iron Oxidation State 
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Copyright information

© Springer Science+Business Media New York 1996

Authors and Affiliations

  • L. E. BoolIII
    • 1
  • J. J. Helble
    • 1
  1. 1.PSI Technologies, a division of Physical Sciences Inc.AndoverUSA

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