Computer Aided Design of Fluidized Bed Reactor for the Production of Polypropylene

Abstract

Fluidized bed reactor (FBR) are the most preferred reaction vessels for reactions involving gas-liquid-solid interaction as they have excellent mass transfer characteristics and exceptional heat distribution system. The fluidized bed consist of two regions: bubble and emulsion phases with an interchange coefficient for transfer of gas between regions. The computation and design of fluidized bed for the production of polypropylene was presented. Three configurations were considered for the plug flow – plug flow configuration, plug flow – mixed flow configuration and mixed flow – mixed flow configuration for the bubble and emulsion phases respectively to investigate the best configuration for highest yield of polypropylene. A computer software (ASPEN HYSIS) was used for the design the three FBR configurations. Results obtained indicated that the plug flow – plug flow configuration produced the highest yield of 51.6mole percent while the plug flow – mixed flow mode had 46.02mole percent and the mixed flow – mixed flow mode produced the lowest yield of 45.19mole percent. However, the mixed flow – mixed flow mode utilized the lowest operating temperature of 194F while the plug flow – mixed flow and plug flow – plug flow modes utilized 202F and 320F respectively, indicating that the mixed flow – mixed flow mode temperature matched plant data for 90^oC (194F). The design capacity of the fluidized bed reactor (FBR) is 4813 barrel/day, 4791 barrel/day and 4639barrel/day for PFR/PFR, PFR/CSTR and CSTR/CSTR configurations respectively.

Keywords: Fluidized Bed Reactor, Polypropylene, Design, Aspen-Hysis, CSTR, PFR, Operating Temperature