(510f) Design of Lab Scale Fluidized Bed Reactor

In the reactions involving gas-solid or gas-liquid interactions fluidized bed reactors are the most preferred reaction vessels as they have excellent mass transfer mechanism and exceptional heat distribution system. For determining design parameters of a fluidized bed reactor three phase model, known as Kunni- Levenspiel (K-L) model, has been followed. K-L model has been found to be closer to the real situation as it considers the three phases in the fluidized bed reactor separately, namely emulsion phase, bubble phase and cloud phase. Mass balance on gases in three different phases:

Mass balance on solids

    

In the present paper K-L model has been used to design the fluidized bed reactor. Fluidized bed characteristics have been determined by using known conditions at minimum fluidization (u_mf, e_mf), and the superficial velocity u_o in the bed.

Reactor dimensions including height, diameter along with heat generated during the reaction and suitable method of distribution of this heat has been estimated in the paper.

The design parameters for the fluidized bed reactor were calculated using MATLAB. The process of fluidization was illustrated further using ammoxidation of propylene for production of acrylonitrile. Physical parameters such as diameter and height for a bubbling fluidized bed reactor were calculated. Also details of mass transfer and heat transfer were estimated and plausible approaches to distribution of generated heat during the reaction are proposed.