Experimental Study of the Fluidization of Geldart A Type Catalyst In a Rotating Fluidized Bed In a Static Geometry

The fluidization of Geldart A type FCC catalyst in a rotating fluidized bed in a static geometry (RFB-SG) was experimentally studied. In RFB-SGs, the particle bed rotational motion is introduced by the tangential injection of the fluidization gas in the fluidization chamber, via multiple gas inlet slots. Three different gas inlet designs were tested, essentially varying the number of gas inlet slots and their size. This allowed evaluating the effect of the uniformity of gas injection and of the amount of energy and tangential momentum injected with the gas. Two different systems for feeding the solids were also considered. In the first, the solids are fed axially via one of the end plates of the reactor, in the second they are fed via one of the gas inlet slots.

Measurements over a range of gas flow rates and solids feeding rates were carried out. The pressure drop over the fluidization chamber and over the particle bed, the solids loading in the fluidization chamber, and the particle bed height, average density, uniformity and rotational speed were determined by means of pressure sensors, high speed cameras, and a rotating flag inserted in the particle bed.

Using the experimental data, the hydrodynamic behavior in a RFB-SG of Geldart A type particles is investigated. The presence of waves in the system and the importance of a free vortex in the particle bed freeboard region are analyzed. The optimization of the fluidization chamber design for the fluidization of Geldart A type and smaller particles is discussed. The potential of the technology for application in Fluid Catalytic Cracking (FCC) and in other processes is evaluated.