petrotrinsmerv
Chemical
- Apr 16, 2003
- 12
We have a vacuum column designed with a three stage overhead (ejector/condenser) system. From inception the pressure obtained in the column was above design (40 mmHgabs compared to design 20 mmHgabs). This was so whether the first stage ejectors were on or not. We had three first stage ejectors with three first stage condensers of equal capacity in paralell. So the first stage ejectors were decommisioned and remained that way for many years. We have been told that the original design first stage condenser pressure of 64 mmHgabs was too low for 86 degF cooling water (seawater). Uncondensed steam would load up the second stage condensers. Does this claim seem reasonable. For a three stage system, what would people normally design for the first condenser pressure to ensure adequate steam condensation.