Does anyone have experience with old cement silo aeration system using pipes?

These systems were used in the 60's and 70's and they were pipes with a lot of small holes and the whole pipe was wrapped with a fabric. Compressed, dry air was then injected to the pipes at low pressure.

What I'm looking for is precisely the working pressure of that kind of systems.

Help is appreciated.

Jose L. Quintal

jose.quintal @cemex.com ■