Dry Ice Blasting
What Is Dry Ice cleaning?
It is the process in which dry ice particles are propelled at high speed to
impart and clean surfaces. The particles are accelerated by compressed air,
just the same as other blasting systems. Most applications are able to use
standard shop air, in the 80-100 p.s.i. range.
How does It work?
It depends on what you are cleaning. If you are
removing a brittle contaminant such as paint,
the process creates a compression tension wave
between the coating and the substrate. This wave
has enough energy to overcome the bonding strength
and literally pop the coating off from the inside
out.
What happens to the dry ice once it strikes the
surface?
It sublimates and returns to the atmosphere as
carbon dioxide (CO2) gas. CO2 is a naturally
occurring element.
How is dry ice made?
It is made from liquid CO2, which exists as a liquid only under high pressure.
When it drops to ambient
pressure (the normal pressure that surrounds
us), approximately half turns to gas and half
turns to solid. The solid, usually is the form
of fluffy snow, is then compressed to form dry
ice blocks, pellets, or nuggets.
How are dry ice pellets made?
Pellets are made by taking liquid CO2 from a pressurized
storage tank and dropping it to ambient pressure
to produce snow. The snow is then pushed through
a die to make pellets.
How
do I store my dry ice?
Since dry ice is -109 degree F, putting it in a
freezer at 32 degrees F doesn't really help.
The best way to extend your shelf life is to
store the ice in an insulated bin. Depending
on the quality of the bin and how much ice you
are storing, your loss due to sublimation should range from 2% to 10% per
day.