Fluidized Bed Reactors

Fluidized Bed Reactors

Parr Fluidized Bed Reactors are used extensively in the chemical process industries. The distinguishing feature of a fluidized bed reactor is that the bed of solid particles or catalyst is supported by an up flow of gas. This reactor provides easy loading and removal of catalyst. This is advantageous when the solids bed must be removed and replaced frequently. A high conversion with a large throughput is possible with this style of reactor. Such reactors inherently possess excellent heat transfer and mixing characteristics.

Fluidized beds have been significantly utilized in chemical processes, in which parameters such as diffusion or heat transfer are the major design parameters. Compared to packed bed, a fluidized bed has notable advantages such as better control of temperature, no hot spot in the bed, uniform catalyst distribution and longer life of the catalyst.

Nearly all significant commercial applications of fluidized bed technology concern gas-solid systems. Applications of fluidized bed reactors include but are not limited to gas-solid reactions, Fisher-Tropsch synthesis, and catalytic cracking of hydrocarbons and related high molecular weight petroleum fractions. Gasification in a fluidized bed can be utilized to convert coal, biomass and other waste materials into synthesis gas.

The reactor system pictured on this page includes the following key components:

  • A gas handling and mixing sub-system used to blend and regulate the flow of reactant gas to the bottom of the reactor.
  • The reactor is roughly one meter long with a 2.5 cm ID.  The lower portion of the reactor incorporates an easily replaced porous metal gas diffusion plate and the top of the reactor widens abruptly to form a disengaging zone for the fluidized bed.  Separate heaters are provided for both the main reactor and disengaging zone.  A movable thermocouple in a thermowell is provided for monitoring the internal reactor temperature distribution.
  • A heated cyclone separator or filter is provided immediately downstream of the reactor to capture the fines resulting from particle attrition.
  • The reaction products are then cooled by a condenser and collected in a 600 mL product receiver.
  • The system pressure is maintained by an automated, dome-loaded, back pressure regulator.
  • All system functions and parameters are monitored and maintained by a Parr 4871 Process Controller (not shown).