The S5 pilot-sized mill has a cryogenic cover with vent and a phase separator, along with two charging ports for added versatility. The mill has an actuated ball valve assembly that enables remote discharge of the liquid nitrogen slurry. Featuring a 10 HP explosion-proof motor and electricals, the mill also has a variable frequency drive to control agitator speed. The drive displays Hz, RPM and HP. An operator station is mounted on the unit with start/stop push buttons and a speed potentiometer.