Influence of simulated MSW sizes on the combustion process in a fixed bed: CFD and experimental approaches

This work presents the effect of the simulated sizes of Municipal Solid Waste (MSW) on the combustion process in a fixed bed experimentally and numerically. The effect of temperature, gas emissions, flame front velocity and process rate are discussed for three different sizes of MSW: 10, 30, and 50 mm. The study found that for the operating conditions of the current model, when the diameter of particles is decreased, the bulk density of the material is increased, resulting in a decrease of convective heat transfer as well as combustion speed. As the diameter size of the material particles increase, the height of the post-combustion zone is increased, while the temperature in a high temperature area is decreased, due to the decrease in the material's bulk density and the excessive increase in porosity. Results also show that the average emission concentration of CO and CO₂ decreases gradually with an increase in the particle diameter size.