Sweetwater Condenser Subcooling

[GBurns]

Does anyone know how much subcooling is possible (typical) in a sweetwater condenser? Steam at saturations (534 Deg F) with feedwater entering in at 350 Deg F. Our design shows very little however we have about 150 Deg.F subcooling right now. Of course this may indicate a leak, however, the condenser is operating a much lower flow rates than design.

 

[TD2K]

Sounds like you have the tube bundle partially/mostly flooded with condensate in which case you can get a lot of subcooling. Can you estimate where the steam/water boundary is on the steam side? How do you remove the water from the steam side after it's condensed? I suspect you'll find that most of the bundle is full of condensate and you are approaching the inlet feed water temperature due to the low rates you are running.

I doubt it's due to an exchanger leak. Just by a thermal balance, you can see that most of the combined stream leaving the condensor would have to be feedwater to get 150F subcooling of the steam (534F - 150F = 384F. Given your latent heat, you'd have to leak a LOT of 350F water to get a combined outlet temperature of about 384F).