Patent ID: 11872593
Assignee: AGT-USA, INC.
Field: Chemical engineering (Chemistry)
Classification: CPC B | IPC B

Claim 7:
8. A sifting system for separating small components from larger components of plant stock comprising:
a plurality of sifting tray assemblies 2, including at least a first sifting tray assembly 2A and a second sifting tray assembly 2B, wherein each sifting tray assembly comprises:
an upper enclosure 6 with an inlet aperture 7 located at a first, inlet end 12 of the upper enclosure, and a large particle outlet aperture 8 located at a second, outlet end 13 of the upper enclosure;
a sifting screen 4 having a first end and a second end, said first end of the sifting screen proximate the first end 12 of the upper enclosure and the second end of the sifting screen proximate the second, outlet end 13 of the upper enclosure;
a cryogen injector 24 disposed proximate the first end 12 of the upper enclosure, said cryogen injector configured to supply a cryogenic fluid to plant stock entering the upper enclosure 6;
a bottom pan 3 with a first end 12 and a small particle outlet aperture 5 located at a second end 11 of the bottom pan 3, and a top open to the sifting screen 4, and a bottom 3B with a closed surface;
wherein the sifting screen 4 is disposed between the upper enclosure and bottom pan;
wherein the sifting screen 4 is disposed between the upper enclosure 6 and bottom pan 21;

(d) a first container 44 in communication, through a first hose 45, with the outlet 8 for discharge of the large particles, for collection of the large particles and (e) a second container 42 in communication, through a second hose 43, with the outlet 5 for discharge of the small particles, for collection of the small particles; wherein
the first container 44 is a closed container with a first vent 46 communicating from the first container 44 to ambient atmosphere and the second container 42 is a closed container with a second vent 46 communicating from the second container 42 to ambient atmosphere;
a filter system in fluid communication with the sifting system, said filter system comprising;
a pump 50 for drawing cryogenic fluid from the sifting system;
a filter 49 for filtering any small particles entrained in the cryogenic fluid drawn from the sifting system and forced through the filter by the pump 50.