Dust removal cyclones. I will build the design that draws air from vent hoods within the building up to the cyclone. I'm guessing there were a number of bag dump stations in the compounding area.
I got the knife to cut through the .010" styrene on the third try. It's a vertical adjustment to the knife blade and you just have to try some settings until it's good. The cyclone itself is a Walthers part from Red Wing Flour Mill I think. I was gifted several of them in a rough built up condition.
A small build plate really helps with assembly as it allows the assembly to be rotated to the position best allowing part placement. Smear some paste on the hardboard. The uppermost part goes down first, then work your way to the bottom of the part.
This would be natural 3D print project and Mike Skibbe's wig wag crossing signals have got me thinking. Ugh. Best to not think too hard.