
• Principle :
Low temperatures allow to harden and to weaken substances to grind.
• Advantages :
- Preserve physical and chemical characteristics of heat sensitive products
- To grind products of very different nature with an homogeneous particle sizing
- To directly obtain finest powders with minimum power and retraining
- To optimize the treatment capacity of the installation
Air Liquide achieves turnkey installations and liquid nitrogen pre-cooling materials, adapted to different products to be grind.
Today 2 techniques are used for freeze-grinding :
• The cryogenic screw :
- Very efficient for in-line treatment of product whose out-flow is difficult
- Fast cooling and a high temperature accuracy
- Excellent output
- Total recovery of residual refrigerates from the grinder
• The hopper to pulverization :
- Vertical system designed for in-line treatment of sensitive products to cluster
- Simple and compact design
- Fast cooling and excellent output of refrigeration (recovery of the sensitive heat of cold gases)
- Helical wiper who assures the granules out-flow and the temperature homogenization