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 also essential to reduce the possibility of contaminating your product. 
• To protect the surrounding environment from aggressive tank fluid escaping into the environment.

Benefits of tank vent filters:

• Increased safety: With reduced risk of bacteria and VOCs, consumers can be confident that the product they consume is safe, and the plant can be confident that it will comply with regulations.
• Extended shelf life: Contamination prevention extends the shelf life of the final product, preserving its freshness and guaranteeing its quality over time.
• Reduced production and equipment costs: Airborne contamination can lead to costly product recalls and damage to downstream equipment. Without vents, product storage tanks would implode or explode due to pressure variations.

Tank Vent Requirements:

• Removal of particles and micro-organisms: Tank vent filters must effectively capture and remove dust, airborne debris, bacteria, viruses and volatile organic compounds. High particle and micro-organism filtration efficiency is essential to prevent contamination of the final product.
• Air flow capacity: Air flow capacity must be sufficient to meet the ventilation and air flow requirements of the tanks. Ensure that there are no excessive pressure drops or flow restrictions, which could damage storage tanks.
• Longevity and durability: Filters must have a long service life and be resistant to wear and tear. Filters must be able to withstand environmental conditions and maintain their filtration efficiency for an extended period without frequent replacement.
• Regulatory compliance : Filters must meet the regulatory requirements and standards set by the relevant authorities, such as the Food and Drug Administration (FDA) or other local regulatory bodies. Make sure that the filters you select comply with these regulations, to guarantee the safety and quality of the final product.
• Compatibility with existing systems : Tank vent filters must be compatible with existing venting systems and the design of tanks used in the process. Consider compatibility aspects to ensure seamless integration and smooth operation of the filtration system.

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

Want to know more about tank vent filtration? Please download our application brochure!

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