Effect of Pressure Fluctuations on the Quality of Fluidization and on the Generation of Particulate Matters during Incineration

With good quality of fluidization the air flows uniformly through the bed and the particles are distributed well in the fluid stream, which may improve combustion efficiency. However, the effects of operating parameters and characteristics of waste on generation of particulate matters (fly ash) and quality of fluidization were rarely evaluated. This study investigated the relationship between the quality of fluidization and generation of particulate matters during incineration. The operating parameters included waste characteristics, operating gas velocity, and temperature. The statistical and power spectrum analyses were used to assess pressure fluctuations. The experimental results showed that when the combusion temperature was controlled at 600°C, the mean amplitude was reduced and the dominant frequency was increased, indicating that the quality of fluidization was better than for other conditions. Consequently, generation of fly ash during incineration was minimized when the combustion temperature was controlled at 600°C. The more amount of fly ash was generation with acrylonitrile–butadiene–styrene (ABS) combustion at different conditions, and combustion of wood generated the least amount of ash. It may be that the wood combustion is quite stable and the combustion behavior of ABS is the most violent among the four plastic wastes. Notably, the dominant frequency increased with temperature for wood combustion, and the quality of fluidization was improved at 800°C. For different results of U/Umf, they did not have obvious tendencies. Consequently, behavior of the bed material and quality of fluidization determined the generation of fly ash. Therefore, the combustion efficiency may be enhanced by improving the quality of fluidization.