Selecting the right aeration filters for tanks involves more than you think. In the process industry, many tanks are used to store raw materials and finished products.
The tanks are filled and emptied regularly with process fluids. To prevent them from imploding or bursting apart, there is an open connection to the outside. Through this opening, the tank is aerated and vented.
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Keeping the tank and liquid clean.
‍To keep the tank clean inside, but also to keep the liquid clean, an aeration filter should be fitted on the tank opening. Depending on the application, bacteria (food and beverage) or dirt particles must be stopped. In some cases, moisture (water) must also be kept out.
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Selecting the right aeration filter.
‍To select the right aeration filter, I always ask customers about the conditions under which the filter must operate. In other words, the specifications. I also want to know the purpose for which the customer is going to use the aeration filter.

With the conditions / specifications you can think of:‍

• ‍The flow of venting during the process. In most cases this is the pump flow that empties the tank.
  
• The flow of aeration. In some cases, the tank is filled via an external pump (tanker truck), whereby the capacity is many times higher than the de-aeration flow.
• The maximum (design) pressure of tank.
• The maximum vacuum of the tank.
• Are there any connections already available? If so, what is the size and/or type of connection?
• What is the location of the setup? Indoors or outdoors?
• Are we dealing with a sterile environment?
• Will tank still be cleaned in the process, for example with chemicals or steam?

With the conditions / specifications you can think of:

• ‍What needs to be stopped? Dirt or moisture?
  
• If dirt particles need to be stopped, what is the maximum size and/or is the dirt distribution known?
  

Variations
The above information ultimately determines the selection of the aeration filter housing and filter element. The choice of micron rating is quite wide, from 0.05 micron to 1 micron for PTFE membranes. For microfiber media, it is up to around 30 microns. These two media are the most commonly used. PTFE has the advantage of also being hydrophobic (water repellent). Metal or sintered elements can also be used as aeration filters. In that case the fineness varies from 0.7 to 100 microns with air (99.9%).
More info on PTFE filters here.
More info on Metallic filters.

‍Which desiccant?
For keeping moisture out, a combination of a filter with a desiccant is usually applied. Silica gel, molecular sieve, activated alumina or activated carbon are used as drying agents. The field of application may also impose certain requirements on the selected products with regard to certificates. For example, filter housings can be supplied with Ce, ASME or 3.1b certificates. Specifically, elements conform to USP ClassVI or NSF61.
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As you can see, there is a lot involved in a tank aeration issue. We are happy to assist you in selecting the right solution in the area of aeration filters.

Our filters are suiteble to replace:
‍Pall Emflon
Sartorius Sartofluor
Amazon SupaPore
Eaton's LOFMEM