The minimum fluidization velocity (Umf), which is defined as the superficial gas velocity at which the drag force of the upward moving gas is equal to the apparent weight of the particle bed seems to be a more tractable parameter in fluidization.

https://link.springer.com/chapter/10.1007/978-94-009-4400-8_9

I think you should start with experimental research. While there are many criteria equations in the literature that can be used to estimate the minimum fluidization velocity, the question is whether they can be applied to your biomass.

I would like to know if we know the minimum fluidizatiin velocity, how to calculate the diameter of the reactor?

I understand you determined the Umf without experimental research and by using a correlation for the feedstock flow rate. In this case, you should refer to the assumptions and criteria of that correlation and check whether they can be applied to your feed. Different parameters affect each correlation like L/D, size and density of the particles (which type of geldart), the density of the fluidizing gas, etc. It would be best if you consider the more general correlation for your work.

Hamed Hoorijani Is there any general L/D aspect ratio corelation?

Muhammad Shoaib Ahmed Khan I'm not sure. My research mostly involves experiments of nanoparticle fluidization. My lab partner used the reference below for her work with micro-size particles (Geldart B) to determine the Umf for cylindrical and semi-cylindrical fluidized bed. It would be best if you studied the literature to find the best model that suits your feed properties (particles), facilities, etc. and consider the model's criteria and assumptions in the design.

https://doi.org/10.1002/aic.690120343

Upon reflection, I believe that you should use specialized software such as Aspen Plus. This is not a project. which can be realized by means of correlations from the literature. Not only geometry and hydrodynamics are important, but also kinetics.

Mirosław Grzesik I am using Aspen Plus so I have to provide reactor dimensions as input.

use this thesis to design the fluidized bed