Pollution prevention project: Xerox development of carbon dioxide (CO2) blast cleaning

The CO₂ cleaning system was adapted from a jet-engine cleaning technology and is being used for removal of grease, dirt, and oil from used (field-returned) equipment to enable machine remanufacturing. Prior to the introduction of CO₂ blasting, machine cleaning was a two-stage process, which required a variety of chemicals. In the first stage, loose dirt was removed by compressed air blow-off and vacuum suction. In the second stage, a blend of chlorinated solvents was applied, typically in a handwipe application. In the 1980s, Xerox replaced the solvent blend with a citrus-based material for general cleaning but continued to use 1,1,1-trichloroethane on encrusted, stubborn dirt. Xerox made a significant financial investment in adapting CO₂ blasting technology for use in its remanufacturing facility and the cleaning of mechanically and electronically sensitive machine parts. This development effort entailed redesign of the current process equipment and recalibration of the blasting parameters. Furthermore, ergonomic refinement of the equipment was required to permit its use by an operator over an 8 to 12 hour work shift. Development and implementation of this new system allowed Xerox to meet an internal requirement of eliminating all ozone depleting substances from its manufacturing processes by the end of 1992, years ahead of any regulatory initiatives. Moreover, CO₂ blast cleaning resulted in unanticipated cost-savings of 40% and productivity improvements of 50%