3 replies to this topic

[Andree]

I just wanted to ask if polypropylene filtration media can operate at low temperature, as low as -150 Celsius = approx. -300 F, gas filtration? I did not find any information about limitation for lower temperature and only for maximum allowable temperature (which is about 80-90 deg. Celsius).

I will appreciate any comments etc.

[abhi_agrawa]

Andree,
I am not sure whether you will have some filtration related problems, however going to low temperatures could mean changing the MOC to Low Temperature CS or even SS. May be the economics governs this.

abhishek

[Art Montemayor]

Andree:

I would seriously doubt if you can depend on polypropylene (or any thermoplastic) working successfully at such low temperatures. One of the major tradeoffs to expect when using plastics and elastomers is that they inherently have a relatively narrow temperature range where they can be relied upon for design purposes.

I believe you normally do not see sub-freezing temperatures in the ratings tables because these materials are reknown for becoming very brittle at sub-zero temperatures. You can check me out on this with the manufacturer - which should be your first and expert choice of opinion - and when you do, please let us know in this thread what was the official response.

[Andree]

Hi All,
To those who replied: thank you for contribution.
Maybe description of my issue was not very precise. The vessel is made of low temperature carbon steel, and only the filtration internals are polypropylene (cartridges which are made of seamless tubes).
This is slightly different issue when the meterial is in form of fibers (felt). I am sure that at low temperature it becomes brittle as well. But I believe that there is not much stresses inside the cartridge (only those resulting from pressure drop accross if properly mounted) and the structure is reinforced by support core made of SS. Except becoming brittle, there is also another issue re how the low temperature will change the structure (e.g. pore size) due to thermal contraction.
I did not hear from manufacturer yet (Andrew Webron, Ltd.) - as soon as I get response I will let you know what the official statement is.
Andree