Abrasives Overview Abrasive cleaning removes contamination from a surface by blasting it with small pieces of solid material. The solid material is called the media and is usually propelled by air or water. An example is sandblasting. Traditional abrasives include sand, metal particles, plastic pellets, and organic media such as crushed walnut shells. Abrasive cleaning processes have also been developed using carbon dioxide pellets, wheat starch, and bicarbonate of soda. Carbon dioxide is frozen to form pellets, which return to gas phase after use leaving behind only the removed debris as waste. Wheat starch is reported to become more effective with use. Wheat starch and bicarbonate of soda are both used as mild abrasives. Abrasive cleaning effectively removes surface layers such as rust and scale, but is not usually a good choice for fluid removal. Parts may require chemical cleaning after the use of some abrasive media, because media residues may corrode the part. Operators may need respirators or other protection from fine particles suspended in the air. Most processes generate waste that consists of the cleaning media combined with the removed soil or metal. This waste may be hazardous, in which case it will require special handling and disposal. State Information | Glossary | Conversion Checklist | Comments Home | Process Advisor | Alternatives | Links | Search All SAGE material, Copyright© 1992, Research Triangle Institute Last Update: 10 March 1995 sage@rti.org http://clean.rti.org/alt.cfm?id=ab&cat=ov