2. Process principle

The process involves spraying the material to be removed (coating or deposit) with a supersonic, cryogenic, dense, pressurized jet of nitrogen. To achieve stripping results on resistant coatings such as industrial paints, ceramics or metal alloys, the nitrogen is sprayed in a supercritical state, i.e. at a density close to that of water and with the viscosity of a gas.

Figure 1 shows the principle of a cryogenic nitrogen jet treatment plant