Vacuum Dryer De-Lumping and Powdering Included: Vacuum Dryers Can Do More Than Just Dry Filter Cakes
Products from centrifuges or filtration processes often come in the form of wet, lumpy cakes — powdering and drying are usually important processing steps. Combining de-lumping and vacuum drying within a single step can bring big benefits for the industry while providing excellent quality even of sensitive products.
Since its establishment in 1939, Italvacuum has manufactured industrial vacuum pumps and vacuum dryers for chemicals, pharmaceuticals and cosmetics. The company has a tradition of developing original and innovative solutions for its customers’ needs. Their most known product is the Criox system — a multi-product rotary vacuum dryer with lump-breaker, which removes water and organic solvents from wet filter and centrifuge cakes, and yields lump-free powders.
The Criox system is versatile and multi-purpose as it can also be used as a rapid blender, homogenizer and granulator. By combining these functions and reducing the need for downstream milling, it minimizes the time needed to change products, including cleaning, washing, and inspection. Applications cover intermediates and finished products, including fine chemicals, pharmaceutical ingredients and chemically reactive materials. Product characteristics include temperature sensitivity, the need for delicate handling, a variety of particle sizes, and special properties such as sterility or photosensitivity.
De-Lumping Makes the Difference
The biconical rotating drying chamber of the Criox provides extremely homogeneous mixing and effective drying. The rotational speed of the chamber is adjustable, and at slow speeds even mechanically fragile products can be treated without damage.
What sets the Criox apart, however, is the two powerful sets of lump-breaking blades. By continuously renewing the surface area of product exposed to evaporation, the independently powered lump-breakers improve the effectiveness of mixing and considerably reduce the drying time. Criox thus dries the product to extremely low moisture levels, that other systems often cannot achieve. It also allows effective drying at low temperatures, and so avoids the degradation of even the most heat-sensitive products.
As well as breaking up the incoming wet cake, the lump-breakers stop the forming of new lumps. The dried product has a controlled final particle size distribution, and typically requires only sieving before it is packed.
Criox is available in capacities of 55–12,000 liters. Even large breaker units can work with small batch sizes, being effective even with just a few liters of product.