Mathematical modeling of nox emissions in bubbling fluidized bed combustors

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2005

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Afacan, M. Onur

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A comprehensive model, previously developed and tested for prediction of behavior of continuous fluidized bed combustors is extended to incorporate NOx formation and reduction reactions and applied to the simulation of METU 0.3 MWt Atmospheric Bubbling Fluidized Bed Combustor (ABFBC) burning lignites with high volatile matter in their own ashes. The predictive accuracy of the model was assessed by comparing its predictions with measurements taken previously on the same rig. Favorable comparisons are obtained between the predicted and measured temperatures and concentrations of gaseous species along the combustor. Results show that determination of partitioning of coal nitrogen into char nitrogen and volatile nitrogen, and release of volatile nitrogen along the combustor are found to be the most important parameters that affect NOx formation and reduction in bubbling fluidized bed combustors. The system model proposed in this study proves to be a useful tool in qualitatively and quantitatively simulating the processes taking place in an atmospheric fluidized bed combustor.

Subject Keywords

Chemical engineering.

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http://etd.lib.metu.edu.tr/upload/12606463/index.pdf
https://hdl.handle.net/11511/15466

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Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

M. O. Afacan, “Mathematical modeling of nox emissions in bubbling fluidized bed combustors,” M.S. - Master of Science, Middle East Technical University, 2005.