RO downstream or upstream HE/Flowmeter

[rob5377]

Hello,

RO has to be installed in circulation pipe for scrubber to reduce circulation flow-rate. There is a heat exchanger and flowmeter installed as well(pump discharge, manual valve, HE, manual valve, flowmeter, manual valve, scrubber) . The question is where is the best place to install RO?
1)Downstream HE
2)Upstream HE
- upstream flowmeter
- downstream flowmeter

Thanks for any suggestions.

 

[chief]

The RO will increase the velocity of your fluid and cause some fluid turbulence. This could cause problems with your HE (tube erosion and poor heat transfer).For those reasons it is best to place the RO at the outlet of the HE.

Offshore Engineering&Design

 

[sshep]

As this application sounds like a liquid full system, the RO can pretty much go anywhere in circulation loop with equal effect. Best to look for an easily accessible set of available flanges that has some up stream (and downstream) straight length. This straight run will give best chance to insure the actual flow is close the desired flow used to size the RO. Also you won't want to put the RO between any equipment and the pressure gage locations that would be used for performance monitoring (especially applies to pump and exchanger).

Barring installation directly on the exchanger inlet flange (not recommended per above), I struggle to understand Chief's concern about the velocity and erosion. These temporary effects should fully dissipate within 5-10 pipe diameters downstream.

best wishes,
sshep