High pressure liquid receiver

[PEPELEBU]

Hello guys it has been some time without me coming here, I'm working on a new project and some of the conditions on specifications for making a full skid equipment to power two ice generators is something I have been looking the reason why customer is demanding this:

- Refrigerant is going to be R449A (Even after my strong opposition, still wondering why they are not using R717)
- Two compressor in parallel - OK no problem here.
- Oil separator - OK no problem here.
- Air condenser - OK no problem here.
- Valves - OK no problem here.
- High pressure liquid receiver, here they are demanding to be horizontal vessel with a 30º inclination. According the technical guy of my customers say these helps to reduce the amount of refrigerant in the installation.

On my idea, this might helps to increase the "height" of liquid so could assure liquid velocity at the exit of the receiver. If I were to use R717, I also could understand assuring on the lower level to accumulate oil so I can drain on the bottom... but because they want to use R449A, oil is going to be set on top of the liquid level. So NO explanation to me.

Any documentation available on this topic, or explanation on why this helps improve in any how the system?

As always appreciate your inputs...

Dani

[RANGER1]

Dani,
If liquid receiver has this 30 degree angle it probably need less refrigerant, why not go vertical?
Oil will not accumulate, because of high circulation rate of the refrigerant, liquid out from bottom, new liquid in at top all the time, so lots of mixing.
Liquid line out, is it a dip tube from the top, or coming of the bottom?
Still need enough liquid level for a liquid seal under all conditions.
Relief valve would have to be at higher inclined end to ensure gas only.
Assume sized so you can pump out ice generators, does it have to be big enough for both to be pumped down at same time, as that makes it much bigger.

What are dimensions of liquid receiver?

Probably some consultant who has to have some input to justify their selves.

[PEPELEBU]

Ranger, thanks on quick response.
Receiver for both machines 350 lt. If my decision and want to save space of course I would set it up vertical.
The guy making the spec on the horizontal does not give a technical reason no justification just saying they will reduce amount of refrigerant...because they say so.
Because I will be making the skid, if I choose receiver will come from bottom.
Totally agree on the relief valve position.
Volume will be able to pump down one of the two units and still have some room but not possible to do 100% pump down in both machines.
With this refrigerant density if much higher than oil, so some accumulation on top will occur, but I'm planning to avoid that with a very nice oil separator.
Thanks
D

[Josip]

Hello guys it has been some time without me coming here, I'm working on a new project and some of the conditions on specifications for making a full skid equipment to power two ice generators is something I have been looking the reason why customer is demanding this:

- Refrigerant is going to be R449A (Even after my strong opposition, still wondering why they are not using R717)
- Two compressor in parallel - OK no problem here.
- Oil separator - OK no problem here.
- Air condenser - OK no problem here.
- Valves - OK no problem here.
- High pressure liquid receiver, here they are demanding to be horizontal vessel with a 30º inclination. According the technical guy of my customers say these helps to reduce the amount of refrigerant in the installation.

On my idea, this might helps to increase the "height" of liquid so could assure liquid velocity at the exit of the receiver. If I were to use R717, I also could understand assuring on the lower level to accumulate oil so I can drain on the bottom... but because they want to use R449A, oil is going to be set on top of the liquid level. So NO explanation to me.

Any documentation available on this topic, or explanation on why this helps improve in any how the system?

As always appreciate your inputs...

Dani

To reduce amount of requested refrigerant within system it will be ok to use vertical receiver with bottom outlet pipe ...

For me installation at angle of 30º has no meaning ... not to use some other word ... but there were always some people selling "snake oil" why not now !?

That technical guy knows why receiver must be installed with an angle and for other people no need to give any explanation ... WHY NOT? ... because there is no logical explanation ...

Anyhow, I would also like (very much) to see some documents/s with explaination of benefits ...

Height of liquid within receiver has no affect to liquid velocity i.e. additional pressure to liquid going to evaporators ... this is high pressure vessel and only difference in pressure will push the liquid to evaporators without any problem ...

Liquid height can play a role only in low pressure separators ... enough height between liquid level and pump inlet and that is the reason to install low temperature separators at certain height to assure static pressure at pump inlet ...

Reason to use R449A or any other "green *****" is quite simple ... ammonia plant is more expensive to install, but on long run is cheaper ... but that is something what generally is not presented or explained to customers ...

Best regards, Josip