Combustion Modeling and Performance Evaluation in a Full-Scale Rotary Kiln Incinerator

ABSTRACT

This work summarizes the results of numerical investigations and in situ measurements for turbulent combustion in a full-scale rotary kiln incinerator (RKI). The three-dimensional (3D) governing equations for mass, momentum, energy, and species, together with the k - e turbulence model, are formulated and solved using a finite volume method. Volatile gases from solid waste were simulated by gaseous CH₄ distributed nonuniformly along the kiln bed. The combustion process was considered to be a two-step stoichiometric reaction for primary air mixed with CH₄ gas in the combustion chamber. The mixing-controlled eddy-dissipation model (EDM) was employed to predict the conversion rates of CH₄, O₂, CO₂, and CO. The results of the prediction show that reverse flows occur near the entrance of the first combustion chamber (FCC) and the turning point at the entrance to the second combustion chamber (SCC).