2 replies to this topic

[M.Sadiq]

FLARE K.O Drum

 

As per API-521, for Sizing Flare K.O Drum, the liquid droplet removal size shall be considered as 300 - 600 microns and considering no mesh pad. because in general a flare stack can handle small amounts of finely dispersed liquids (300 - 600 microns). What is the reason behind not using mesh pad ? Can a deflector plate install in vapor outlet instead of mesh pad ? Vane type (Diffuser) inlet Device can be used ?

 

VENT K.O DRUM

 

While a vent stack can only handle dry gas. So, for sizing of Vent K.O Drum What is the liquid droplet removal criteria to make gas DRY? Except Droplet removal Criteria, is the sizing criteria is similar to Flare K.O Drum ? Furthermore, the use of mesh pad in Vent K.O Drum is allowed ?

 

 

Please help me in this regard.

 

 

 

Thanks!!

[Erwin APRIANDI]

Hi M.Sadiq,

 

FLARE K.O DRUM

Q: What is the reason behind not using mesh pad ?

Answer: As I know, since Flare System shall be very reliable, that is why the use of mesh pad is not adviseable, since the mesh pad at the outlet gas may plugged. However API 521 also gives recommendation on inlet/outlet configuration at section 7.3.2.1 (API STD 521, 2007 adendum 2008).

 

Q: Can a deflector plate install in vapor outlet instead of mesh pad?

Answer: Yes, API 521 recommend the use of deflection plate or baffle to minimize carry-over

 

Q: Vane type (Diffuser) inlet Device can be used ?

Answer:  API 521 recommend inlet baffle only, noy diffuser. And I never see diffuser use before for inlet nozzle of Flare KO Drum

 

VENT KO DRUM

Q: So, for sizing of Vent K.O Drum What is the liquid droplet removal criteria to make gas DRY?

Answer: Based on API 521, The atmospheric knockout drum shall be designed to knock out liquid droplets such that any remaining droplets or the plume cannot reach working areas, property line or other critical areas at a hazardous concentration. The droplet size criteria for atmospheric knockout drums should be more stringent than for flare knockout drums (See 7.3.2.1) because most flares are capable of burning small droplets. Based on Norsok Standard use 300 micron

 

Q: Except Droplet removal Criteria, is the sizing criteria is similar to Flare K.O Drum ?

Answer: Based on API 521, The design of the atmospheric knockout drum shall meet the design criteria for flare knockout drums in 7.3.2.1

 

Q: Furthermore, the use of mesh pad in Vent K.O Drum is allowed ?

Answer: Based on API 521, The design of the atmospheric knockout drum shall meet the design criteria for flare knockout drums in 7.3.2.1, so it is not allowed.

 

http://www.standard..../P-SR-007r1.pdf

 

Additional, actually you can find all this in API STD 521 without have to post it here

[M.Sadiq]

Erwin Apriandi
 

Thanks for your valuable answers.

 

This is really helpful for me.

Edited by M.Sadiq, 31 July 2013 - 01:34 AM.