Micron filter

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Hoosier

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I am wondering if anyone has any experience on a micron filter

As I understand, there are two kinds of micron filters, no filter replaceable or filter replaceable ones.

Based on my research, no filter replaceable one can be cleaned out through backwashing. I was told that 2 micron filter is recommend based on ANDI standard. However, 2 micron is very tiny pore size so that even a bacteria can be caught. If so, how often should we clean it out? How long does this filter last with a simple backwashing?

Thanks for your insight in advance.
 
Hoosier:
I am wondering if anyone has any experience on a micron filter

As I understand, there are two kinds of micron filters, no filter replaceable or filter replaceable ones.

Based on my research, no filter replaceable one can be cleaned out through backwashing. I was told that 2 micron filter is recommend based on ANDI standard. However, 2 micron is very tiny pore size so that even a bacteria can be caught. If so, how often should we clean it out? How long does this filter last with a simple backwashing?

Thanks for your insight in advance.

The main thing its meant to catch is rust particles.. Particle impingement is a possible ignition source for oxygen fires.. Usually backflushing is all that is needed unless it gets contaminated by something that causes permanent damage..
 
Hoosier:
I am wondering if anyone has any experience on a micron filter

As I understand, there are two kinds of micron filters, no filter replaceable or filter replaceable ones.

Based on my research, no filter replaceable one can be cleaned out through backwashing. I was told that 2 micron filter is recommend based on ANDI standard. However, 2 micron is very tiny pore size so that even a bacteria can be caught. If so, how often should we clean it out? How long does this filter last with a simple backwashing?

Thanks for your insight in advance.

"Micron" is a measuring unit, not really a type of filter. 2 microns is small but it takes about .5 -.2 to remove bacteria. Or so the manufacturers of water filters tell me.
 
Hank49:
"Micron" is a measuring unit, not really a type of filter. 2 microns is small but it takes about .5 -.2 to remove bacteria. Or so the manufacturers of water filters tell me.


Yes, it is also called as an inline filter. I think 2 micron is pretty much market standard for an air purification.
 
NASA and the military, tight azzed as usual, specify something like 2 microns as maximum acceptable particle size. The theory behind this is that a larger particle can serve as the nucleus for an ignition. That is, the particle creates a spark or gets hot somehow and serves as an igniter for a larger fire in an oxygen environment. On the other hand, experience of numerous divers suggests that the dacron 40 micron filter pad provides adequate protection. (That is still a very small particle). The principal contaminant of concern is carbon produced by filtration systems. Another particle, hydrated iron III (rust) is not a concern to my knowledge. An iron or steel particle is thought to be a sparking hazard but most PP mixers use brass components with which to decant larger bottles and fill their tanks. Nevertheless, most brass oxygen regulators contain a filter of some type. Personally, I use micronic filters. One would expect that from a guru, right? Well, when running out of things to do I seek to solve tenuous, even imaginary, problems. Two common types are the disk (filter cartridge) and the cylinder (in line).. The disk type micron filter contained in the Lawrence Factor cartridge is compressed magnesium silicate. In line filters can be stainless or ceramic. Silicates are powdery stuff and the disks have to be enclosed in a fold of coffee filter paper. The stainless inline from Compressed Air Specialties contains a replaceable core. However, they should last a long, long time in any case. In fact, the stainless disk type can be cleaned in acid or solvents. I doubt that the other types can be cleaned successfully. Micron filters are also used as condensers and are very effective in that application. They will last forever so long as they are not mounted directly in the air stream. Normally, they are mounted in the top of the canister so that the air dumps its particles before flowing through the filter. Hope this helps.
 
Check out the following capture from McMaster site:

About_Micron_Sizes_and_Particle_Filtration.jpg


I think 2 Micron filter is a little bit overkill though. Like I said, it looks like a market standard for an air purification.

In the meantime, I have researched about an inline filter and talked with many experts including LF and GMC...

As for a back washing, there are two groups of thought.
There are two groups of thoughts: back washing or replacement.

The pore size is so small that the simple back washing isn't enough to clean out an element EVENLY. Once it is moisturized over time, it is done. There is a rust issue, too.

The other group argues that we can have a simple air back washing and simple green soaking. It will last many years.

Hence, it is also depending on the type of element.


The placement of an inline filter is also depending on your priority, either an air or canister. Many chamber designs put an inline filter after the canister. LF and Scubacompressor also did in this order. I also put an inline filter after a canister.
 

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