Filters elements used for tank vent filtration are typically sterile air/gas cartridge filters. They should be hydrophobic, as those filters are wetted out either due to surrounding air humidity or exposure to steam airflow into and out of the tank. They should retain airborne microorganisms and even viruses (ex. bacteriophage), depending on the application. Moreover, they should be correctly sized to avoid tank damage.

Liquids are pumped into and out of tanks regularly. When the tanks are filled, air is forced out of the tank as incoming liquid volume displaces air volume. When they are emptied, surrounding plant air is drawn into the tank to replace liquid volume. Tank vent filters must be properly sized so that they do not hinder this airflow in forward or reverse direction, in order not to change the equilibrium pressure in the tank.

Tank vent filtrater sizing is especially critical in applications involving tank sterilization in place (SIP) with steam. After tank sterilization, the steam cools down and condensates rapidly, creating an instantaneous volume change and negative pressure.

Why it’s important to have tank vent filters :

• To reduce batch contamination, spoilage, and product loss, effective sterile submicron filtration is a necessary part of your process. Especially important in the pharmaceutical industries, sterile filtration protects your product from harmful submicron particle contamination and bacterial transfer or growth. 
• To maintain safe, balanced pressure during the filling or emptying of a storage vessel, tank vent or breather filters are essential to reduce the possibility of contaminating your product. 
• To protect the surrounding environment from aggressive tank fluid escaping into the environment.

We recommend using our GFTVE sanitary vessels along with our hydrophobic membrane cartridges (PFTE or polysulfone) for your tank vent filtration.

Don’t hesitate to contact us to discuss your tank vent filtration!