Liquid separator with the slots on the wet return distributor - how to design?

[Artur Żuk]

Please let me how to design ammonia liquid separator with the slots on the wet return distributor (In the annex is an example).
If you've ever seen such a solution, please send me the information about it
Probably the inlet slots can much reduce the volume of the liquid separator.

15098

[RANGER1]

Artur,
I am not expert on design, but no slots on wet return.
Have seen a type of baffle plate directly under return on horizontal vessel.
Basically helps distribute liquid ammonia on re-entry to prevent large flow in one spot, possibly effecting level & gas bubbles.
Usually opposite end of vessel away from liquid pumps & control column.

See page 6 in link below

http://www.ishraepune.org/documents/Liquid%20overfeed%20systems%20by%20R.%20P.%20Paranjpey.pdf

[Artur Żuk]

Dear RANGER1,
Thank you for that document. There is some kind of the liquid separators what i am using at the moment (In the annex you can find the this type of separator - slightly modified) so i am not interested such solution.
15099

I am interested especialy the separators with the slots on the inlet distributor.
There are 2 types of distributors with inlets slots.
1. First with slots directed towards down of the tank. There is small velocity on the slots and it is looks for me like "the speed of drops increases the force of gravity" - maby we should to add this two forces?
2. The second with slots directed towards the ellipsoidal end. This probably uses the cyclone principle because there is a high speed on the slots and the drops should go on the ellipsoidal end and after fall down.

I would like to know how to calculation such solutions.

[RANGER1]

This download from IRC may help, as well as lots of good information.

http://www.irc.wisc.edu/file.php?ID=21


Danfoss coolselector 2 download could also assist
or Coolpack

[Josip]

Hi, Artur :)
welcome to RE forums ...


Please let me how to design ammonia liquid separator with the slots on the wet return distributor (In the annex is an example).
If you've ever seen such a solution, please send me the information about it
Probably the inlet slots can much reduce the volume of the liquid separator.

15098

I must agree with Ranger1 regarding slots ... we do not use them but ... anyhow this is one way how to divert direct flow from return line to suction line .... so by "slots" or some other mechanical part (like baffle plate) we turn direct return wet line down to liquid and gas is going back up to suction line ... hope nothing is lost in this translation ...

Whole meaning of "slots" or "baffle plates" is to extend the traveling way, within separator, from inlet of wet return line to dry suction pipe to compressor (you are right - separator comes bigger according to gas speed calculation) ... the point is to reduce gas velocity within separator to max 0,5 m/second to avoid any liquid droplets to be sucked into compressor suction line ...

There is some similar solution for low stage compressor discharge pipe with slots or holes which is submerged into liquid refrigerant in separator of high stage... but this is another case ...

For this reason we usually have wet return line on one side of the separator and compressor suction line on the opposite side ... to have bigger traveling distance to allow liquid droplets to drop down into liquid refrigerant ...

In the old times we used to design separator big enough to avoid any "wet" return in suction pipe to compressor ... point was to keep internal gas velocity at 0,5 m/sec or less ...

Unfortunately, your attached drawing is with too small resolution and details are not visible at all to give you any opinion about (attachment can be up to size of 100 kb) so you can upload a much better drawing if you like.

Of course if you can explain where are you going to use this separator (to give us some better picture) maybe we can help much more ...

Within links posted by RANGER1 you can find a lot of useful information ...

Best regards, Josip :)