Fluidization

The popcorn kernels, all being fairly uniform in size and shape, are suspended in the hot air rising from the bottom chamber.

Because of the intense mixing of the particles, akin to that of a boiling liquid, this allows for a uniform temperature of the kernels throughout the chamber, minimizing the amount of burnt popcorn.

After popping, the now larger popcorn particles encounter increased aerodynamic drag which pushes them out of the chamber and into a bowl.

The process is also key in the formation of a sand volcano and fluid escape structures in sediments and sedimentary rocks.

The first large scale commercial implementation, in the early 1940s, was the fluid catalytic cracking (FCC) process,[1] which converted heavier petroleum cuts into gasoline.

By the 1950s, fluidized bed technology was being applied to mineral and metallurgical processes such as drying, calcining, and sulfide roasting.

In the late 1970s, a fluidized bed process for the synthesis of polyethylene dramatically reduced the cost of this important polymer, making its use economical in many new applications.

[4] The polymerization reaction generates heat and the intense mixing associated with fluidization prevents hot spots where the polyethylene particles would melt.

The cracking reaction is endothermic, and heat is provided through the bed wall, typically made of graphite (to avoid metal contamination of the product silicon).

[12][13] Fluidization has many applications with the use of ion exchange particles for the purification and processing of many industrial liquid streams.