Horizontal Separator Sizing 1

[Riko_93]

I have designed Horizontal Separator for only liquid phase stream which is mostly water. And, i think the settling velocity of gas phase is too high. Vt= 12.85 m/s. Am i right? if yes, how to decrease this velocity. Do i need to use cyclone inlet device? what do you suggest me?
And one more question,
LAL-LAH can be taken as working level/NLL or not.Give a little explanation

 

[LittleInch]

Looks very fast to me. If your vessel is 12m long then the gas would only have one second in the separator...

Either increase pressure to reduce actual velocity or make your vessel a LOT bigger.

No LAL and LAH are ALARM levels.

NLL is normal Liquid level and is usally a single level somewhere between the two. Sometimes in the middle, sometimes more biased to one end rather than the other.

You sometimes get NLLL and NLLH to indicate normal variance in liquid level, but these should be within the limits of LAH and LAL.

The operators will not like you if they keep getting alarms going off for a "normal" variance in liquid level.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[Riko_93]

Is it possible to design vertical Separator for this situation?

 

[LittleInch]

Yes

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[Riko_93]

Hi,
The diameter for vapor handling is too small ( 50mm) because of vapor flow rate. What i should do? Can i calculate dmin using overall volume flow using L/D = 2.5 standard?
L/D=2.5
V= 17.66 m3/h
V=AL = (piD^2/4)*2.5D
D=cuberoot(4V/2.5pi)
What to do in this situation?

 

[don1980]

Riko - Consider buying a separator from a vendor that specializes in the design and fabrication of these vessels. There are probably others, but the company I'm familiar with is Peerless Mfg. Co. They seem to have the lions share of the market here in the US, but they're also a global supplier. Based on personal experience their separators work very well. Back when I was a process engineer I found that the separators that I (and others) designed, using the fundamental rules for separation, were always bigger than separator offered by Peerless for the same application. That caused me to be skeptical at first, but their products worked well. We used them in a lot of very critical applications, such as interstage separators on very large multi-stage compressors. I have no stake in this company - I just know their separators are economical and they work.

 

[Riko_93]

Thank you