How Does Dry Ice Blasting work?
Dry Ice Blasting is an innovative and technically-advanced method of cleaning and decontaminating surfaces with Dry Ice – a solid form of carbon dioxide. The dry ice comes in pellet format which are stored at -79ºC. At Polar IceTech we use various different pellet sizes depending on the type of work we are doing and the component we are cleaning. What Is Dry Ice?
Also know as Cryogenic Cleaning, the process sees the pellets of carbon dioxide go into a specific application gun and are pushed through at the speed of light out through a special nozzle on the end. Just as with the pellets, the nozzle used depends on the size of the application being cleaned, the sensitivity required and whatever substance that needs to be removed (also known as a contaminant in Dry Ice Blasting lingo).
The dry ice hits this contaminant (build up of carbon / dust / grime / grease / tar / glue / food as example) and because the Dry Ice is so cold it causes it to crack and become brittle. When the Dry Ice hit this contaminant at the speed of sound, it sublimates on contact vaporising back into the atmosphere. Meaning that it converts instantly from the solid pellet into a gas. While this conversion is taking place (while the dry ice sublimates), the carbon dioxide gas expands and fully lifts the contaminant off from the inside out without damaging the surface underneath.
To summarise, the image opposite demonstrates how dry ice blasting works:
1. Kinetic Energy: Dry Ice is accelerated through a compressed stream of air at the speed of sound.
2. Microthermal Shock: The speed and temperature of the Dry Ice Blast causes the primary contaminant to crack.
3. Rapid Gas Expansion: The Dry Ice instantly convert to gas and expands breaking up the already cracked primary contaminant.