Dry ice is easily manufactured.
Generally there are common steps taken in producing dry ice. First, gases containing a high concentration of carbon dioxide are produced. Such gases can be a byproduct of some other process
, such as producing ammonia
and natural gas
, or large-scale fermentation
Second, carbon dioxide-rich gas is pressurized and refrigerated until it changes into its liquid form. Furthermore, the pressure is reduced. When this occurs some liquid carbon dioxide vaporizes, and this causes a rapid lowering of temperature of the remaining liquid carbon dioxide. As a result the extreme cold causes the liquid to solidify into a snow-like consistency. Finally, the snow-like solid carbon dioxide is compressed into either small pellets or larger blocks of dry ice.