PDT test on UF membranes

[ashtree]

I am setting up a pressure decay test (PDT) on a UF plant. In simple terms a PDT involves pressurizing with compressed the feed side of the membrane to about 5psi ,locking off the valves and looking at how quickly the pressure decays. This assumes that if a lumen is broken the pressure will leak out through the broken lumen/s and that pressure decay can be logged. Likewise many plants have transparent pieces in the pipework so that the bubbles can be observed, thus the actual faulty module can be determined.

The plant that i am looking at however has modules that the lumens are in an inverted "U" with both ends of the lumens and all the filtrate exiting at the bottom of the module. This means that the bubbles will not be able to be seen.

However if i applied the pressure to the filtrate side instead of the feed side i would be able to see the bubbles potentially if the pipework was suitably arranged. Apart from the fact that it is standard practice to do it from the feed side does anybody know of a reason why pressurising the filtrate side could not work just the same.
The mebranes being used are Mann Hummell UA860s.

Regards
Ashtree
"Any water can be made potable if you filter it through enough money"

 

[EdStainless]

Will these membranes tolerate reversed pressure?
Some will collapse very easily.

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P.E. Metallurgy, consulting work welcomed

 

[ashtree]

Thanks EdStainless

UF membranes can tolerate reverse pressure during backwash so i would expect these to be okay.

Regards
Ashtree
"Any water can be made potable if you filter it through enough money"