Blast Cleaning System

Author:  Jay Armstrong, James R. Becker
Source:  US Patent 5,365,699
Doc ID:  1994009
Year of Publication:  1994
Abstract:  
This invention relates to a carbon dioxide blast cleaning system for propelling dry-ice pellets by cryogens, manely high pressure nitrogen, helium and/or oxygen, against a surface being cleaned. Caarbon dioxide pellets, in a pellet hopper, a blast unit and a blast gun are located at a blast site near the surface being cleaned. A portable cryogenic liquid nitrogen, liquid helium and/or liquid air tank with an ambient air vaproizer is also located at or near the blast site. Cryongeic liquid nitrogen, liquid hilium and/or oxygen flow through the ambient air vaporizer to the liquid and is vjaporized to form a high pressure gas. The high pressure, cryogenic gas is then brought into the blast unit and mixed with the pellets. The mixture of the high pressure gas and the pellets exit the gun nozzle a high velocities to blast the surface being cleaned.