In Krefeld, Germany, Messer operates a highly specialised technical centre for testing cold grinding and recycling applications. A wide range of test equipment is available to you there, including a cryogenic counter-rotating pin mill with an upstream product cooler, a cutting mill equipped with a product cooler or alternatively with mill room refrigeration, a tumbler screen, a vibration screen, and particle analysis technology, along with refrigeration and regulating equipment for on-site testing at customers’ facilities.
The extremely low temperature of the nitrogen facilitates grinding of thermoplastics and prevents agglutination. The results from Krefeld can be applied to industrial-scale processes, because the equipment configuration corresponds to that of a production unit. Spices can also be fine ground in our cold grinding technical centre, which is available for use by the customers of all Messer Group subsidiaries.
In cold grinding, the material to be ground is cooled and embrittled with extremely cold liquid nitrogen or carbon dioxide. This process achieves particularly fine grain sizes while maintaining product quality at the same time. It also significantly increases grinding capacity. Cooling the grinding process with cryogenic gases is especially effective because it protects heat sensitive materials from temperature increases caused by the conversion of electrical energy by the mill’s motors – temperature increases which would otherwise cause the powdered material to melt or become sticky.