Coal Ash Fusion Temperatures — New Characterisation Techniques, and Associations with Phase Equilibria

  • T. F. Wall
  • R. A. Creelman
  • R. P. Gupta
  • S. Gupta
  • C. Coin
  • A. Lowe

Abstract

The well-documented shortcomings of the standard technique for estimating the fusion temperature of coal ash are its subjective nature and poor accuracy. Alternative measurements based on the shrinkage and electrical conductivity of heating samples are therefore examined with laboratory ash prepared at about 800°C in crucibles, as well as combustion ash sampled from power stations. Sensitive shrinkage measurements indicate temperatures of rapid change which correspond to the formation of liquid phases that can be identified on ternary phase diagrams. The existence and extent of formation of these phases, as quantified by the magnitude of ‘peaks’ in the test, provide alternative ash fusion temperatures. The peaks from laboratory ashes and corresponding combustion ashes derived from the same coals show clear differences which may be related to the evaporation of potassium during combustion and the reactions of the mineral residues to form combustion ash.

Keywords

Fusion Temperature Iron Silicate Shrinkage Test Rapid Shrinkage Australian Coal 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer Science+Business Media New York 1996

Authors and Affiliations

  • T. F. Wall
    • 1
  • R. A. Creelman
    • 2
  • R. P. Gupta
    • 1
  • S. Gupta
    • 1
  • C. Coin
    • 3
  • A. Lowe
    • 4
  1. 1.Department of Chemical EngineeringUniversity of NewcastleUK
  2. 2.R A Creelman and AssociatesEppingUK
  3. 3.ACIRL IpswichBoovalUK
  4. 4.Pacific PowerSydneyUK

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