At room temperature, when the carbon dioxide gas is pressurized to about 101325Pa, when a part of the vapor is cooled to about -56 ° C, it will freeze into solid carbon dioxide. The gasification heat of solid carbon dioxide is very large, 364.5J /g at -60 ° C, and the surrounding temperature can be reduced to about -78 ° C when gas at atmospheric pressure, and no liquid will be produced, so it is called "dry ice".
The dry ice medium used in dry ice jet cleaning is to create solid dry ice particles through a dry ice granulator, which can be used immediately or stored in an incubator for backup. These particles are typically 3mm in diameter and 2.5mm to 10mm in length. In this method, the high-pressure liquid CO₂ is ejected from the pipe into a snow-like solid CO₂, and the snow-like CO₂ is extruded into dry ice particles by liquid pressure through the mold.
