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2

# Oil/water Separation- Droplet Size

5 replies to this topic
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### #1 lsoaresfernandes

lsoaresfernandes

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Posted 20 March 2022 - 08:47 AM

Hello,

I have to deal with a situation where I have an existing oil/water separator and have to understand how it will perform in a different scenario (whether with a different oil or the same at different temperatures).

I was thinking about using stokes law and calculate the minimum separated particle diameter.. however, in order to estimate the BSW downstream the vessel, I’d need the distribution of the droplets diameter.

I am aware it depends on many variables, but does anyone have an idea on how to do that?

Thanks

### #2 Bobby Strain

Bobby Strain

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Posted 20 March 2022 - 09:24 AM

You are unlikely to find a solution that is free. You can check my website for what is available free.

Bobby

### #3 lsoaresfernandes

lsoaresfernandes

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Posted 20 March 2022 - 09:37 AM

Hi Bob,

I will check your website, but maybe there is a literature recommendation for that?

I don’t mind doing th calculations my own, I just don’t feel confortable using a “black-box” solution (and Im not aware of any, is there a software for that?).

All documents ever came to my hands on how to calculate those vessels, the droplet diameter was an input.. I am confused on where those values come from

### #4 Bobby Strain

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Posted 20 March 2022 - 11:39 AM

Why don't you explain the changes you are contemplating? What is the oil? And its properties? Separator dimensions? Interface level? Oil & water flow? Internals? Feed distributor? A drawing? .............

My software uses accepted methods for drop settling. Start simple. You don't have to spend time duplicating methods. If you register at my site, you can download an Excel spreadsheet to calculate drop settling velocities. But it's easier to use the web software.

If you download the spreadsheet, you can see all the equations in the VBA editor. I don't use cell formulas.

Bobby

Edited by Bobby Strain, 20 March 2022 - 02:33 PM.

### #5 lsoaresfernandes

lsoaresfernandes

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Posted 20 March 2022 - 08:37 PM

I don´t have the flowrates yet, as well as dimension of the vessel.

This is a new project which is starting and I have not received everything yet. I came to ask this because in the past I struggled a bit to try to understand what BS&W we could expect downstream of a sep. vessel.

Thank you.

### #6 breizh

breizh

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Posted 20 March 2022 - 09:09 PM

Hi,

Some literature to support your work

Good luck

Breizh