Cleaning processes are an important part of industrial production.
In addition to mechanical and chemical cleaning methods, there are a whole range of processes that use water, sand, plastic or glass beads as blasting agents. The disadvantages of these methods are that the abrasive nature of the blasting agents causes wear, they incur costs for disposal and treatment of the contaminated blasting agents, and they involve downtimes for the production facilities.
Cleaning with dry ice pellets offers an alternative that is kind to both materials and the environment.
Information about the blasting medium and how it works:
The blasting medium
Liquid carbon dioxide is stored in a low-pressure tank at approximately 20 bar and at a temperature of around -20°C. When sprayed into a pelletising cylinder, it forms carbon dioxide gas and carbon dioxide snow as a result of cooling and expansion to the ambient pressure. This snow, which has a temperature of approximately -78°C, is compacted and then pressed through a pelletising matrix. This produces dry ice pellets measuring around 3 mm in diameter and 10 mm in length.
How it works
The pellets are accelerated to 100 – 300 m/s using compressed air. They are then sprayed on to the surface to be cleaned by means of special nozzles. When this happens, the blast medium supercools the surface at specific points and removes unwanted coatings and impurities. It is the combination of cold temperatures, kinetic energy and an “explosive” change of state (sublimation) by the dry ice pellets that makes this method particularly suitable for industrial cleaning processes.