Quantum Leap in Dry-grinding Technology
NETZSCH-CONDUX Mahltechnik GmbH from Hanau has presented an innovative development in the field of dry-grinding in the form of the new s-Jet® system at this year´s ACHEMA exhibition in Frankfurt.
This process, for which a patent has been registered, and which has been described by specialists in the field of mechanical process technology as a quantum leap, represents the newest further development in jet-milling. With it, final finenesses in the submicron range (e.g. d50 0.2 µm) can now be achieved.
Contrary to the conventional dry-grinding method of jet-milling, overheated steam is used as a grinding gas in fluidized bed jet mills with the s-Jet® system.
As steam has a considerably higher acoustic velocity than air, the possible peripheral speed of the flow within a classifier wheel increases, and with it also the acceleration power, which affects the product being classified. In this way, in turn the decisive step has been made to actually enable the classification of particles in the submicron range by means of dry-grinding for the first time.
In addition to this, the new s-Jet® system also has interesting commercial aspects: Steam provides a considerably higher flow energy compared to air. Jet velocities of up to 1200 m/s can be achieved and the kinetic impact of the product particles within the fluidised bed increases fourfold! This leads to a considerable increase of the mill throughput compared to the throughputs obtained during operation with air (more than double). Therefore, the throughput of the fluidized bed jet mill operated with steam increases considerably with comparable finenesses!!
Just in time for this year´s ACHEMA-exhibition a complete production scale s-Jet® system has been installed in NETZSCH-CONDUX´s test lab in Hanau. This worldwide unique test plant is now available to interested customers for testing of their products!
Furthermore, at the same time as the ACHEMA 2009, interested users made use of the possibility of experiencing this new plant live. During „s-Jet® goes live!“ demonstrations, especially organized to coincide with the exhibition, this new technology and its advantages has been presented in detail to a number of visitors.