Abstract
Circulating fluidised bed combustors are increasingly commonly used for environmentally sound steam generation from fossil fuels and other low value energy sources. Low uniform combustion temperatures and air staging produce low NOx emissions, while sulphur oxides may be scrubbed cheaply by in-bed sorbent addition. However, optimal design of circulating fluidised bed boilers for maximum multifuel capability and turndown is hindered by a lack of fundamental understanding of the fluid and particle mechanics. This paper discusses how an understanding of the fluid mechanics may be used to scale-up from pilot plant systems to full scale combustors. Key engineering aspects, geometric optimisation, fluid mechanics scale-up, and heat transfer coefficient prediction are each discussed. Observed pollutant formation trends are also rationalised in terms of the solids distributions in the circulating fluidised bed.
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Brereton, C., Grace, J.R., Lim, C.J., Zhu, J. (1992). Engineering Aspects of Recirculating Fluidised Bed Combustion. In: de Lasa, H.I., Doğu, G., Ravella, A. (eds) Chemical Reactor Technology for Environmentally Safe Reactors and Products. NATO ASI Series, vol 225. Springer, Dordrecht. https://doi.org/10.1007/978-94-011-2747-9_21
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DOI: https://doi.org/10.1007/978-94-011-2747-9_21
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