The NETZSCH High-efficiency Fine Classifier CFS/HD-S works very efficiently due to ist closely defined sharpness of cut and ist very specific product flow.
Ultra-fine Grinding and Ultra-fine Classifying on a Laboratory Scale
NETZSCH Trockenmahltechnik GmbH, one of the global leading companies in the area of dry product processing, is part of the Business Unit Grinding & Dispersing of the NETZSCH Group. Customers profit from our comprehensive experience potential and our diverse machine program, ranging from laboratory- and production machines to complete production lines. Fine impact mills, classifying- and jet mills as well as fine-cutting mills and high-efficiency fine classifiers made by NETZSCH are mainly used in the application areas chemistry, inorganic materials/minerals, ceramics and life science for pharma- and food applications.
The CFS-HD classifier uses a combination of the free vortex and the forced vortex models to achieve cut points down to less than 2 µm. The classifier rotor has a new design for theoretically constant radial velocity in the vane-free internal area; it is surrounded by a cage of static vanes, creating a steep spiral flow in order to give good dispersion and deagglomeration to the material to be classified.
Based on the physical model of classification in vaned rotors, the fundamental difference between the exclusive use of a forced vortex flow (i.e. classification at the outer edge of the vanes) and the combined use of forced vortex/free vortex flow (i.e. classification in the interior vane free area) is derived. The classifier used for the comparison is a CFS-HDS model. Results received from this classifier equipped with a ConVor-wheel with constant radial velocity of the flow in the interior vane free area are compared with results from a classifier wheel designed for classification at the outer edge of the vanes.
In the ceramic industry the mechanical treatment of raw materials, processed or finished powders is an important part of many production processes. At the same time the grinding- and classifying processes are also of primordial importance, in order to ensure a range of particle sizes which is usually exactly defined for the particular process. The grinding principle of jet milling has proved itself to be particularly effective for the grinding of ceramic and abrasive materials. They can be ground to high finenesses, with an exact upper particle size limit, in one working step.