Need:150cfm blower to pump pressurized (~40bar) H2 with delta P ~5bar 1

[EtaSystems]

Folks,

I am looking for a blower to produce a flow of ~150cfm (~4m^3/min) while pumping H2 pressurized at ~40bar. The blower needs to provide a pressure increase of ~5bar.

I am wondering if something like a supercharger blower might work.

-Jon Nord, MSEE

 

[moltenmetal]

High flows at significant suction pressures with low compression ratios have always represented a problem for me when searching for compressors and blowers. Very often these services can be a search for a machine that doesn't exist. If you do find one which is perfect for this application, make sure you let me know because I'm very curious what options are out there!

If you cannot find a machine which suits your application, one approach which is awkward but which can be made to work is a "fan in a can"- a low pressure blower installed inside a pressure vessel.

 

[EtaSystems]

Interesting, I was considering a fan in the pressurized system. However, energy usage by the blower is a bit of an issue so I am not sure about the efficiency of a fan designed for ambient pressure air.

Of the limited success that you've had, what have you tried and what has worked best?

 

[moltenmetal]

You can design a fan for the density and Cp/Cv of the fluid you're working with and the efficiency will be fine. Not everybody can do this, but good fan mfgs are up to the challenge.

One good thing is that there are no dry gas seals to worry about- you can get away with a labyrinth seal on the fan itself because the labyrinth leakage will be into the vessel which is what you feed the suction to.

The trick is the drive and bearing design if the motor is outside the can, and electric feed-throughs and motor cooling and maintenance if the motor is to be inside the can.

Often there's another way to re-arrange the flowsheet to eliminate the gas recirc need entirely. That's the easy way out if it's feasible.

 

[EtaSystems]

The cycle time could be up to continuous. The size constraints are based upon gas volume inside the blower. Preferably, the application needs a blower with less than 125cc blower internal volume.

It is looking like the application will need something like a very high speed centrifugal compressor. Maybe something like Rotrex 200000rpm compressors. Maybe something like the Mechanology machines if they are compact enough.