Expansion converts the liquid into the snow form of the solid state. The snow is then compressed by a hydraulic press into dry ice blocks, slices or pellets.

Solid Carbon Dioxide - CO2 is very cold: -78°C. It sublimes (turns from a solid) to an asphyxiant gas that is heavier than air. It is important to note that a little bit of dry ice will sublime to a large volume of gas.