Modelling Fly Ash Generation for UK Power Station Coals
An in-depth characterisation has been made of three UK bituminous coals and the combustion products from these coals when burned at a power station and on a range of experimental combustion facilities. The coals were chosen to represent the range of ash compositions and slagging propensities found at UK power stations.
CCSEM analysis of the pulverised coals has been performed to provide quantitative data on the size and chemical composition of individual mineral occurrences, and to determine the nature of the mineral-mineral and mineral-organic associations in the pulverised fuel. In a similar way the size and chemical composition of individual fly ash particle has been determined.
The mineral-mineral association information has been used predict the effects of mineral coalescence, the dominant mineral transformation process for UK power station coals. The CCSEM information correctly identifies the types of mineral-mineral association that are present, but strongly underestimates the degree of association and hence the predicted effects of coalescence. The limitations of the information are inherent in the analysis of a cross-section, but useful information for the modelling of ash generation may still be obtained.
KeywordsCoal Mineral Mineral Matter Coal Particle Mineral Association Mineral Occurrence
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