New Design of Cross-flow Fluidized Bed Dryers

Drying process demands high power consumption due to the low efficiency of this process in the industries. Therefore, modeling and simulation of dryers in order to optimize them and to design more efficient dryers is necessary. In this research, a cross-flow fluidized bed dryer has been simulated in order to evaluate a new design of the dryer. A mathematical model has been used to predict outlet solid moisture and temperature as well as outlet air humidity and temperature of a single story fluidized bed. The simulation results were evaluated using the experimental data of a pilot cross flow fluidize bed dryer. The comparison showed that the model can reasonably predict the process. Therefore, the simulation was used to investigate a new design of three story dryer (three sequential single story dryers). The simulation results showed while inlet solid moisture was 0.32 and outlet solid moisture for the single-story dryer was 0.19, in the same conditions, outlet solid moisture for the three-story dryer was 0.13. This means the new design can reduce solid moisture by 50 percent more, indicating the better use of hot air and subsequently more energy saving.