2 replies to this topic

[shekhar dhuri]

Dears, 

 

My query here is regarding Process design of two phase and three phase separators in presence Internals (i.e.  Schoepentoeter / Cyclones / Demisters / Sand Jetting headers, Plate Pack Coalescers). 

 

I am using API, GPSA and DEP guidelines and other literature available with me to perform the task.

 

I am creating my simple excel based spread sheets. The key parameter generally asked while sizing the Internals is estimation of Carry overs and % Separation efficiency. For which, I feel, there may be an ‘Empirical Equations’ or ‘Graphs’ available in the literature which I am struggling to find.

 

To give you an example, please find attached excel sheet for ‘MIST PAD’ calculation prepared where I am need help to find % efficiency for 10-micron particle diameter and Carryover (generally less than 0.1 gal / MMscf).

 

I have supplier’s catalogue which do provide me details (mesh density, wire diameter, surface area) of Demisters. Just in case they are required for efficiency estimation. 

 

Similar issues are observed during sizing of Plate Packs (Liquid-Liquid Coalescers). 

 

Please suggest.

 

Thank you.

 

 

  

 

Attached Files

•  MIST PAD - Cal.xls   71.5KB   210 downloads

[Bobby Strain]

 

You really should not size these devices. Instead, prepare a duty spec and provide the vendor with information about the separator. In most services it is unnecessary to know the entrainment after the demister. The vendor will size the demister and explain how it should be mounted in the separator. If you visit my site you will find links to most of the demister providers. And, if you wish, they provide articles to assist you in calculating the values you are interested in.

 

Bobby

 

Edited by Bobby Strain, 22 April 2018 - 04:31 PM.

[walidd_23]

shckare,

 

in each vessel separator 4 stage of separation is required:

 

1- inlet pipe of the separator

2- inlet device

3- gravity section 

4- demisting device ( demister, vane pack..)

 

Separation performance can be quantified  by the carryover and the droplet efficiency.

 

To calculate the carryover( Liquid in vapor or Liquid in Liquid ), the droplet distribution and the separation efficiency of each stage must be determined ,many correlation are involved .

 

there is an automated excel spreadsheet can be used to size process separator with different configuration and determine the performance of the separation ( carryover ).  visit the following website :

 

 https://www.sspcalc.net/

 

Regards

Edited by walidd_23, 30 April 2018 - 01:01 PM.