When liquids contain high solid loads, cake filtration is often used as a physical filtration technology. The liquid passes through the filter medium while the solids form a layer on its surface. During the filtration cycle, this layer retains other particles and becomes thicker, creating the ‘filter cake’.
Once particles start to bridge and build on the filter medium, they become the barrier for further particle retention. The filter medium becomes the carrier of the actual filter – the filter cake – and cake filtration occurs through this.
If the solids present can’t form the first initial layers, then a filter aid can be used to precoat the filter. Filter aids can also be added during filtration to maintain an open structure, ensuring the filter cake remains permeable and that a suitable flux and cake thickness is reached. Typical filter aids include cellulose, diatomaceous earth (Kieselguhr) and perlite.
Cake filtration is typically used in processes where fluids have been brought into contact with active ingredients, such as activated carbon, bleaching earth or catalysts. The characteristics of the liquid, solids and up and downstream processes determine the type of cake filtration used.
Our cake filtration solutions include:
- Horizontal pressure leaf filters
- Vertical pressure leaf filters
- Filter leaves
- Pulse filters and fabric filter cloths
- Horizontal sparkler type filter plates
- Plate and frame filter presses (Seitz Orion)
Tailored filtration solutions to meet your needs
Selecting the right cake filtration technology for your application will depend on many factors like the flow rate, continuous or batch processing, the type and amount of solid load, the nature of the liquid, the temperature and the liquid viscosity.
Our team of process experts recommend solutions to maximise the effectiveness of your filtration process, enabling you to hit production and quality targets with a low total cost of ownership