Wikipedia
Sodablasting
Sodablasting is a process in which sodium bicarbonate is applied against a surface using compressed air. An early use was to restore the Statue of Liberty in the 1980s. It is a very mild form of abrasive blasting, much milder than sandblasting.
Sodablasting is a non-destructive method for many applications in cleaning, paint & varnish stripping, automotive restoration, industrial equipment maintenance, rust removal, graffiti removal, molecular steel passivation against rust, oil removal by saponification and translocation, masonry cleaning and restoration, soot remediation, boat hull cleaning and for food processing facilities and equipment.