The NO and N2O formation mechanism under circulating fluidized bed combustor conditions: From the single particle to the pilot‐scale

The NO and N2O formation mechanism is studied starting from a single fuel particle burning under well-defined conditions up to a pilot-scale circulating fluidized bed combustor (CFBC). The fuel, petroleum coke, was the same in all tests and care has been taken to obtain chemical similarity between the different units: a formation rate unit, a laboratory-scale and a pilot-scale CFBC. A detailed single particle NO/N2O formation model has been developed and incorporated in a CFBC NO/N2O emission model. To thoroughly test the modeled NO/N2O mechanism, the iodine addition method has been used in all units. Le mecanisme de formation du NO et du N2O est etudie a partir diune simple particule de combustible brulant dans des conditions bien definies jusqu'a un systeme de combustion sur lit fluidise circulant (SCLFC). Le combustible, du coke de petrole, etait le meme dans chaque essai, et on a bien pris soin d'obtenir une similitude chimique entre chaque dispositif, soit un appareil mesurant le taux de formation, un SCLFC a echelle de laboratoire et un SCLFC a echelle pilote. Un modele detaille d'une simple particule de formation du NO/N2O a ete elabore et combine a un modele d'emission de NO/N2O provenant d'un SCLFC. Afin de proceder a des essais exhaustifs du mecanisme modelise de formation du NO/N20, la methode a base d'addition d'iode a ete utilisee dans tous les dispositifs.

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