Buffer Gas Spec.

[imans]

Dear Eng-Tip'ers,

I have a plan to change the buffer gas media for centrifugal compressor from pure H2 with 99.9% purity to H2 rich gas with purity between 92 % - 97 % but I dont have any clue whether the shifting will be OK or not. Does anyone has information on the specification or requirement for centrifugal compressor's buffer gas?

Thanks for your help.

 

[mucour]

Imans, what is the type of seal you are using. I mean is it double tandem or single seal? What do you use as your seal gas and separation gas?
Because when you say buffer gas, it means you have different supplies for seal gas supply and separation gas supply in addition to the buffer gas supply.

 

[longeron]

Run the gas composition past your vendor. They will be very happy analyze it and tell you if they recommend a different filter method, a heater to eliminate the possibility of liquids, or even a knock out pot. The three big compressor gas seal mfgs I can think of can also send an engineer or technician out to help you work with your panel to adjust. They have every interest in helping you prolong the life of the seal, thier reputation rests firmly in that.

 

[tgmcg]

With gas seals, priority #1 is to ensure the buffer gas is absolutely clean. With double gas seals, we inject N2 between the seals. Yes...THAT clean.

If you are using gas seals, then I would try to dissuade you from switching to a less pure buffer gas.

If your talking about buffer gas injection "inboard" of the seals, then a low quality gas may do.