Modeling and thermal performance analysis of a dense gas-solid bubbling fluidized bed reactor

In this research, a two-fluid model with the kinetic theory of granular flow was applied to simulate a dense gas-solid bubbling fluidized bed. In order to demonstrate the advantages of gas-particle flows, important parameters in economic design of a bubbling fluidized bed such as air temperature, the maximum required height of the reactor as well as power were compared with a similar simple channel. Results showed that air temperature in the bubbling fluidized bed has a uniform distribution and is much higher than the air temperature along the simple channel at a lower reactor height and with an equal efficiency. Furthermore, effects of air velocity, particles properties and diameter on thermal behavior were investigated. Investigations were performed to introduce the optimal operating conditions to heat up the air stream that is required in industrial units. It was concluded that sand powder with higher air temperature, lower cost and also lower bed height that reduces the required height of the reactor and operational costs, was the most efficient solid material among the other studied materials. Air temperature increased with decreasing the air velocity and increasing the particles size at a constant gas velocity, within the range of the examined bubbling regime.

Keywords:

Gas-particle flow , Bubbling fluidized bed , Two-fluid model , Heat transfer performance