Filtration Technology – Filtration Systems

Filtration technology is a mechanical separation process used to remove solid particles, macromolecules, microorganisms, or viruses from liquids. It involves the use of a specific membrane, which is made from various materials depending on the requirements. This process allows undissolved components to be retained, while dissolved substances can pass through the membrane.

Depending on the desired separation limit of undissolved components, different membranes and special materials are used. The pressure drop during filtration, which indicates filter resistance, plays a central role in this process.

The liquid to be filtered is passed through a membrane – in the case of ETL products, the liquid is drawn through because the filtration process runs from the outside in. The membranes are made from materials such as polymer, metal, or ceramic, each offering specific resistance to the particles within the mixture being filtered.

During the filtration process, retained particles collect either as a layer on the surface of the membrane or within its pores. As the filter cake builds up, flow resistance increases, which can slow down or even halt the filtration process. This may reduce the quantity of the filtered product (permeate) and, when used with online measurement systems, can result in insufficient permeate volumes for measurement. To avoid failures, regular removal of the filter cake or deposits is required – for example, by backflushing, compressed air, chemicals, or manual cleaning.