Utility connection to Oil/Water Separator

[chemicalengr]

I am looking to provide a permanent piping connection from a nitrogen utility station to a high pressure separator for purging/pressurization purposes. Design pressure on the nitrogen system is 1400 kPag, while the separator system is designed for 4500 kPag. What protections are required on the N2 system to prevent overpressure/contamination due to backflow? Is a PSV required, or would a double block and bleed (with check valve) be sufficient to isolate the two systems during operation?

 

[ash9144]

double block, bleed, check valve and slip blind unless it is frequently used

 

[MortenA]

Dosnt the separator allready have a PSV?

If so - a RO should limit the flow rate at set pressure to less than the PSV set-point and you should be on the safe side.

Best regards

Morten

 

[chemicalengr]

Morten,

My concern is protection of the N2 system. A RO will only limit the rate at which the N2 system could be subjected to overpressure.

I'm considering recommending a removable spool (1" line) as this connection is only required periodically and this will eliminate the majority of the risk involved.

Thanks.