Theoretical Considerations about the Steady State Combustion of Wood Char in a Bubbling Fluidized Bed Reactor

Carlos Pinho

Transport Phenomena Research Center, Department of Mechanical Engineering, Faculty of Engineering, University of Porto, Porto, Portugal.

DOI: 10.4236/epe.2013.53021                

Abstract

A theoretical study on the performance of steady state bubbling fluidized bed burners is presented using a simple mathematical model. The proposed model has pedagogical and practical advantages due to its simplicity. The calculations, whose results are plotted in several graphics, were based on data obtained in laboratory scale experiments. The experiments were carried out with wood chars and the model allows a proper evaluation of physical and chemical phenomena taking place inside the reactor, as well as a fast approach to the pre-design phase, before going towards more complex and time consuming numerical modeling. In the first part of the paper the steady state modeling is compared with the combustion of successive batches of char particles. Afterwards, the performance of a 1 m diameter bed operating from 700℃ to 800℃ is shown.

Keywords

Biomass; Wood Char; Fluidized Bed

Conflicts of Interest

The authors declare no conflicts of interest.

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