Abstract: Dry ice is produced by using the internal energy stored in a pressurized CO2 tank or cylinder, which is usually between 300 to 350 PSI, to compress CO2 snow. This same internal energy works whether using a low-pressure refrigerated tank of 300 to 350 PSI CO2, or a high-pressure tank of 800 to 900 PSI CO2, as controlled by a pressure safety valve, to compress the CO2 snow. No other form of mechanical energy is required to make the solidified dry ice.

Abstract: A lightweight, highly mobile and efficient apparatus for instantaneously producing a high volume of solid carbon dioxide (CO2) pellets. The apparatus utilizes liquid CO2 that is discharged and expanded through a nozzle or nozzles and expanded to reach a triple point condition where liquid, gaseous and solid phases of CO2 can coexist and flash to a mixture of CO2 in a gaseous phase and particles of snow by a process well known in the art. The gaseous CO2 is discharged into atmosphere or recovered for converting back to liquid or used to also extinguish fires. The snow particles are aggregated into larger flakes and compressed into pellets in a compression structure by a rotor with radially movable blades forming variable volume pockets associated with the interior of a housing to compress the flakes into pellets.