How can dry ice blast cleaning work without causing any additional waste?

The procedure consists in dry ice pellets being shot on to the contaminated surfaces at high speed. As they impact against the surface, they evaporate into carbon dioxide, thus expanding by as much as 700 times its original volume. This process causes those impurities which are to be removed to shock freeze. They become brittle and fall loose.

Advantages
Dry ice blast cleaning is a new, innovative technology which has been developed as an environmentally-friendly, safe and cost-efficient alternative to cleaning with brushes and spatulas. For certain structures it is to be preferred to sand blasting as well.  

The advantages of dry ice blasting at a glance:

• Environmentally friendly: Stubborn contamination may be removed without producing any ”new“, additional waste products
• Scope of use: May be used where water, sand or other cleaning agents are not admitted. Consequently, this procedure is also suitable for electrically controlled machines and food production machines.
• Compact and mobile: The cleaning equipment is brought to the object to be cleaned, and not vice versa.
• Time and cost saving: The plant to be cleaned does not need to be dismantled, transported or undergo any after-treatment.
• Unabrasive: Unlike procedures such as sand or grit blasting, or cleaning with brushes, this technique is not abrasive.