We have mobile machines of varying capacity in Aussy.
Commercial ones mounted on semi trailers do 25 T/hr.
For other cleaning jobs there are ones that use [either individually or in combination] -
indented screens [catching 'trough' adjustable to pick the grain you either want to keep, or the other you want to discard at the point each falls out of the indents.]
shaking sieves [see next below!]
rotary seives [lots of different slot size, or shot hole size screens]
air blast. [dust and light rubbish/chaff]
These are smaller = but last one I helped aa mate clean canola with was running 8 tonne/hr. Excellent job - saved a heap in dockage/ buyer cleaning fees.
A few farms own their own - others [majority in our area] hire by the hour from a commercial cleaner.