Cleaning, polishing and grinding

Cryocleaning

During the printing process most parts of the printing press get contaminated by all kinds of substances like dried ink, paper dust, grease, oil, coatings, varnish, etc. The conventional cleaning methods need aggressive solvents which are toxic, hazardous and can be flammable. An additional problem are long downtimes. Using dry ice cleaning takes away most of those problems and gives substantial benefits to the user.

The cleaning agent (dry ice pellets) is very soft like plaster, thus creating no scratches, wear or damages, even on sensitive surfaces. When the cylinders are removed all surfaces are accessible and can be cleaned in a fraction of the time needed before. This gives a dramatic reduction in downtime. Further savings will result from the absence of disposal costs.

Did you know?

● To produce crumb rubber, it is necessary to reduce the size of the tire shred or chip. This is accomplished by techniques called cryogenic grinding.

● Cryogenic processing refers to the use of liquid nitrogen (−196°C) to freeze tire chips prior to size reduction. The rubber is immersed in liquid nitrogen to reduce the temperature of the tire chip. The cooled rubber is then ground in an impact-type reduction device.

Bleaching

Ozone is an attractive alternative to chlorine-containing chemicals as a way to bleach pulp and achieve the necessary level of brightness. It is widely used for both TCF and ECF bleaching. As it is an extremely effective bleaching agent, ozone reduces the volume of other bleaching chemicals required.

Grinding

Cryogens can be an effective way to reduce the size of materials that cannot be ground under normal conditions. Many materials that are resilient at ambient temperatures become brittle and glass-like under low temperatures. As a result, these materials can be pulverised through impact or shearing. This form of grinding can also be used to create unusual particle shapes or sizes.

Various materials are suited to cryogrinding. For instance, materials that are tacky or oily can often be solidified and ground. Products that are heat-sensitive can be processed at a temperature level that allows them to be ground without degrading or melting. In addition, cryogenic impact can debond multicomponent materials such as chrome-plated ABS (plastic). And spices can be ground without loss of volatile oils and flavours, thus preserving and enhancing their quality.