Specialist chemical treatments are often required in the process and petrochemical sectors, so that delivered and installed equipment is in good condition and fit for purpose. One special treatment is chemical cleaning for applications where oxygen will be used or transported. This process is generally called oxygen cleaning. The purpose of oxygen cleaning is to condition the surfaces of systems through which gas mixtures with a high concentration of oxygen are passed, often under pressures, typically of 40 bar.
Ultra-clean surfaces are necessary for oxygen production because the smallest traces of contamination will combust spontaneously if they come into contact with pure oxygen and may even lead to an explosion.
The type of cleaning required depends on both the amount of contamination and the type of material involved. Quite often, the surface treatment involves only degreasing, but other acid-based cleaning stages are sometimes required.
Because the cleanliness requirements for oxygen applications are severe, intensive inspection is carried out on the treated components. Final inspection can take place by UV light, a wipe test or an evaporation test with chemically pure solvents to be able to ensure the removal of all organic contaminations.