2 replies to this topic

[Paper]

Dear all we have recently started MCB recovery in vacuum and the scheme is as follows:
MCB vapours from the reactor gets into primary HE, where we have cooling water to condense the MCB. The carryover vapours are directed to secondary HE, which in turn is connected to the vacuum pump. The distillate from both HE is collected in a decanter (Water vapours are also in the system with MCB vapours).
Now my decanter has a balancing line which is connected to the vapour carryover line from primary HE to secondary HE. This is supposed to balance out vacuum difference in all the equipment in series.
We have a balancing line from the U-loop of the decanter (which is provided at the outlet of decanter to ensure layer separation and provide retention) which connects to the same spot in vapour carryover line from primary HE to secondary HE.
Receiver vessel is at atm.
Now the problem statement is, I assume that the balancing line of the U-loop is there to provide anti siphon effect. So, if it's wrong, please tell me the reason.
Second, when I have -550 mmHg vacuum, the MCB will not leave from decanter.
However, as soon as I bypass the U-loop, the collection starts, and even if close the bypass later, the collection becomes stable and continues without assistance.
So what's the reason behind collection, only once the bypass is open and some flow is there. There is no collection to the vessel at atm from vaccum via U-loop independently.

Sorry I couldn't really post a picture, else it would've been much easier to explain.
Looking forward to get some answers.

[latexman]

Sorry I couldn't really post a picture, . . .

Why not? The website has attachment functionality.

[breizh]

Hi,

Definitely a sketch is necessary! 

Click on More Reply options button then Choose file and attach it. Simple, right?

 

I suspect one or more of your valves leaking because the driving force is Pressure or Vacuum in your case.

Breizh