When designing a two phase horizontal separator, what is the minimum retention time required in order to have good separation?
what measures can compensate for a short retention time, due to size limitation?
Hi,
I guess it's a liquid- liquid separator!
a)Can you perform a lab test? This is the best way to get relevant data. Use a graduated flask and a stopwatch.
b)Coalescer.
Pierre
Thanks,
(for some reason I can't seem to find the specific reply to each response, so I'll reply in one post)
The process is separation of n-Butane (gas) from water (liquid).
about 10 bara and 80 °C (though the pressure and temperature can vary).
flow ratio is about 8%[sub]vol[/sub] gas in mostly liquid flow.
The assumed bubble size is about 0.1 mm.
I am looking for ways to improve separation and avoid bubble running with the liquid.
I did a preliminary sizing of a horizontal separator, but need to reduce the retention time, as i am limited with size.
In order to compensate for the short retention time, I assume that some sort of a coalescer is needed, maybe in addition to flow manipulation (buffles).
I would appreciate any input on the options and how each contributes to the separation.
OP, I am not a process engineer, however, I will try to respond within the limit of my process knowledge.
Use Stokes Law to calculate the rising velocity of the bubble.
For the horizontal vessel, the residence time below the low level will be that, that will allow the minimum bubble size to travel the distance between the vessel bottom and the low liquid level.