Principle

Dry Ice Cleaning is a blasting technique similar to sand blasting, but makes use of solid CO2 or dry ice pellets. On impact the pellets vaporize to carbon dioxide gas and increase in volume by a factor of 700. Due to this expansion the contaminant is lifted and separated from the base material.

The advantage of using dry ice pellets as blasting material is twofold (see animation):

1. The very low temperature of the dry ice pellets (-78°C or -109°F) causes the contamination to freeze and contract resulting in the easy detachment of the contaminant from the substrate.

2. The dry ice pellets vaporize to carbon dioxide gas on impact, which means that only the original contaminant is left for disposal. This natural evaporation of dry ice pellets is a major advantage of the dry ice cleaning method.

Animated explanation of the required equipment: