In traditional crossflow filtration, the feed is pumped to prevent a clogging layer from developing on the surface of the filter membranes. However, this method is neither efficient nor viable when handling sensitive or highly viscous products. Therefore the Dynamic Crossflow Filter (DCF) was designed by ANDRITZ SEPARATION. In its process chamber, overlapping rotating disks generate a differential speed. This set-up generates a crossflow without requiring a pump to circulate the slurry and without any circulation line at all. The stationary principle of crossflow causes a zone of discontinuity at the entrance to the overlapping zone. This zone of discontinuity creates a very efficient, local cleaning effect due to the turbulent flow. The turbulent flow is directed in parallel, but also perpendicular to the membrane surface. It is the perpendicular component, in particular, that generates high detaching forces, even in highly adhesive clogging layers.
Mineral oil can be contaminated by a range of different components that are difficult to remove. Often mineral oils are used as a lubricant or cooling medium in the metal working industry, for example in grinding or polishing machines, but are also found in forging or stamping machines. Such oils become contaminated in the course of time with various liquid and solid impurities. There is also a risk of fine metal particles accumulating. Different technologies are applied, such as paper filters or precoat filters, which use a substantial amount of consumables. Centrifuges are also commonly used. The recovery process is becoming more and more difficult, the finer the particles are and the higher the viscosity of the oil. Even highly viscous gearbox oils can be purified with the DCF, while the technology still delivers a particle free filtrate.
The DCF is the latest technology for quick and easy on-site regeneration of the lubricants by removing 100% of the particles, without requiring consumables. By obtaining the highest possible retentate concentrations, the volume of oil losses is minimized and production costs are thus reduced...
Session: M6 - Dynamic Cross Flow Techniques
Day: 13 October 2016
Time: 09:00 - 10:15 h