Dry ice, is the solid form of carbon dioxide. It is used primarily as a cooling agent. Its advantages include lower temperature than that of water ice and not leaving any residue (other than incidental frost from moisture in the atmosphere).
Dry ice is frequently used to package items that must remain cold or frozen, such as ice cream or biological samples, without the use of mechanical cooling.
One of the largest mechanical uses of dry ice is blast cleaning. A dry ice blasting machine is used for that. The new development is quickly expanding around the world. One system uses small rice size pellets of dry ice shooting them out of a jet nozzle with compressed air. It works somewhat like sandblasting or high-pressure water or steam blasting,with superior results.