It depends on your material and the the specifications of the fluidized bed reactor. The Min Fluidization velocity can be obtained both by observation if the reacror is an transparent on or else the plot between the pressure drop and gas flow rate. The point where the graph becomes a steady one (approx. parallel to x-axis) is the flow rate for the minimum fluidization conditions. After that using the formula Q=V/A, you can calculate the min. fluidization velocity.

Thank you

A simple air-tunnel experiment for your material can be performed easity for exact measurement. Be specific at what moisture your are conducting the experiment. You may refer:

Bitra, V.S.P. 2013. Physico-mechanical, aerodynamic, thermodynamic, and thermal properties of peanut pods, kernels, and shells. In “Peanuts: Bioactivities and Allergies”. Iván López Expósito and Ana Belen Blazquez, Editors. Nova Publishers, New York, USA. pp. 21-76.

In addition to the previous answers , parameters such as particle size , gas flow rate , ratio of particle height to bed Diameter ( aspect ratio) , bed height , gas flow distributor , and probes position are important , and for estimation of minimum fluidization velocity( Umf) , there are some correlations with Reynolds and Archimedes number , but the newest methods are analytical with Standard deviation(SD) , Skewness and Kurtosis .

Puncochar et al. found the linear relation of pressure fluctuations and gas velocity after Umf ( SD=A*U+B) , So you can see the related articles and for more this two articles can help you :

1- Experimental investigation on the hydrodynamics of a gas–liquid–solid

fluidized bed using vibration signature and pressure fluctuation analyses

*Rahmat Sotudeh-Gharebagh , Navid Mostoufi

2- A novel approach for simultaneous hydrodynamic characterization

of gas–liquid and gas–solid systems

*Navid Mostoufi , Rahmat Sotudeh-Gharebagh

It depends on material and system properties,

Try to search for article

"Typical Fluidization Characteristics for Geldart's Classification Groups"

It may be very useful for you.

Normally, you determine the size and weight of your catalyst (use fcc commercial cata as ref), then, adjust the flow rate to find the best fluidization condition.

In another way, if you cannot change your flowrate in a wide range, you have to modify your catalyst.

BR

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Dear Olive Green, I regret that your question came to my notice only now. I hope you have got all the answers you need in the meantime. I also have to say that your question is extremely fuzzy. First you want to know if Fluidization parameters can be controlled. Then you ask "how long" it will take to determine parameters "such as" minimum fluidization velocity. What other parameters do you have in mind?

Is your system particulate or aggregative? Most parameters are easy to control in both. As for minimum fluidization velocity, Professor Jack Howard in his book has stated that it is best not to depend on correlations but to perform your own experiments. Visual observations can be misleading. The best would be consider the intersection of the lines for packed bed and fluidized bed in the Δp- superficial velocity plot.

How long? If your system is built and ready to fly, this experiment should take less than an hour.