CO2 Radiological Surface Decontamination
Low-impact, low-waste decontamination solution
Effectively decontaminating surfaces without creating secondary waste is a critical challenge for nuclear plants and other sites undergoing decontamination and/or decommissioning. EAI meets the challenge with its advanced CO2 surface decontamination capabilities. First introduced to the nuclear industry in 1989 by EAI, our specialized equipment, together with our industry-leading expertise and proven processes, enables EAI to achieve superior results without generating secondary waste. EAI’s CO2 process represents an attractive alternative to dry media blasting, hydro lasing, and other methods used for loose surface contamination.
EAI employs specialized equipment to convert liquid CO2 into solid pellets and to blast the pellets at the surface to be cleaned. Liquid CO2, stored under pressure, is transferred to a pelletizer, where rapid depressurization converts the liquid to a solid state in the form of dry ice snow. This snow is then compressed and extruded through a die to form tiny pellets. Then, combined with compressed air through a blasting nozzle, a pressurized stream of CO2 pellets traveling at 75-1000 feet-per-second are projected onto the items or area being cleaned.
The pellets are projected onto the surface in a manner similar to sand or grit blasting, however, the cleaning dynamics of CO2 pellet blasting are dramatically different and vastly superior. Instead of the “chiseling” action associated with conventional grit blasting, the CO2 pellets penetrate the contaminant layer and, upon impact, sublimate to a gas, expanding the volume of the pellet by 750 times lifting the contaminant from the surface. The contaminants are then entrained into the HEPA filtered negative air recovery system, filtered and released back into the atmosphere. The physics of CO2 pellets offers important advantages, as described below.
- Superior Loose Surface Decontamination – CO2 delivers more effective decontamination due to its expansion effect, extended cleaning duration and unique flushing action.
- No damage – Because of its unique cleaning dynamics, CO2 decontaminates effectively without damaging or changing the dimensions of the substrate being decontaminated.
- No residual waste – Because the CO2 pellets sublimate from a solid state to a gas as they strike the substrate, CO2 cleaning does not create secondary waste. The only waste generated is the contaminant removed from the substrate.
- Mobility – Our state-of-the-art Mobile Decontamination Facility (MDF) enables EAI to perform CO2 decontamination virtually anywhere. Because it is a dry process, CO2 blasting can be performed around electrical equipment.