What are the risks of Not Using Vent Filters?
Many processes require the use of tanks for holding ingredients to be added into the process, mixing of ingredients, or to hold the final product pending final filtration and filling. During the course of normal operations these tanks will be filled and emptied many times. Tanks must be vented to allow air to escape as the tank is filled, and then to re-enter as the tank is drained. Structurally, improper venting could lead to catastrophic tank failure such as implosion or explosion. Before looking at why the vents on these tanks need to be filtered, let’s review the venting process.
Pressure buildup during filling.
As a tank is filled, process liquid displaces the air already in the tank. If the air has nowhere to go, pressure inside the tank will increase as the liquid fills more of the tank, compressing the air into a smaller volume. If the process fluid is being pumped into the tank, this pressure could build high enough to cause the tank to rupture, spilling its contents (costly, valuable goods) and requiring expensive cleanup and repair.
Vacuum buildup during emptying.
As a full tank is being emptied, if air is not allowed in to displace the liquid it will start to create a vacuum within the tank. If the process is gravity fed from the tank, it will probably just stop flowing as the vacuum offsets the force of gravity. But if the tank contents are pulled out by a pump, this could create enough of a vacuum to cause tank implosion. Again, this will lead to a spill requiring clean up, loss of product and tank repair or replacement.
Why use a tank vent filter?
First, a tank vent will allow air from the surrounding environment to enter as the tank is being emptied. There are contaminants in that air (dust, particles from other operations, bacteria, etc.) that can negatively affect the tank contents. Second, as the tank is filling, air will escape into the surrounding area. Vent filters serve to protect the local environment and workers from the material in the tank. If your ingredients and products include toxic materials, gases or release fumes that cause illness, it is critical to use a vent filter. Industry regulations and manufacturing guidelines will dictate the necessity of environmental control. Your applications, tank location (clean room vs. factory floor) and processes will further define the need. In some cases it may be necessary to do environmental testing to identify the particulates and contaminants in the area, which will then determine the correct vent filter. The nature (particulate or biological), size distribution and concentration that may be present in the tank air space will help determine the appropriate filter.
Don’t hesitate to contact us to help you optimize your tank vent filters! We will be happy to help!