1) Industrial process
Found on
https://www.crosswordclues.com/clue/trommel-screen
A trommel screen, also known as rotary screen, is an essential unit which is used mainly in the mineral and solid-waste processing industries. It consists of a perforated cylindrical drum which is normally elevated at an angle at the feed end. Physical size separation is achieved as the feed material spirals down the rotating drum, where the under...
Found on
http://en.wikipedia.org/wiki/Trommel_screen
No exact match found.
