Breaking strong oil in water emulsion

[Iradah]

Hello all,

I am seeking your advice on the following:
The inlet separators are now oversized due to lower plant inlet, I thought that this should be helping in the emulsion as it provides more residence time, however, when one of the inlet separators was isolated for a while, other vessels showed better level control, I could not collect analysis, but looks like it was less emulsion. How can the over sizing affect the separation and emulsion?

The HP inlet separators operate at around 90 psig, water then goes to second separation stage at 35 psig, and then it flows to big settling tank at atmospheric conditions. Water clarifier is currently injected at the outlet streams from the second stage separation. This system is not efficient in breaking emulsion, I am thinking of installing a coalescer in this system. Can you give me some hints to proceed, suggest some suppliers, I am staying at UAE.

Thank you.

 

[bimr]

It would help to have some process parameters and analyses.

 

[MortenA]

The most common methode for emulsion breaking includes heat and chemicals.

 

[Iradah]

What are the parameters needed?
Thanks.

 

[Tipp2239]

Use a combination of a cationic polymer water clarifier followed by an anionic water clarifier.

 

[Iradah]

Tipp2239,

Can you please explain more how to use them, do you mean injecting cationic polymer water clarifier at one point in the system and then inject an anionic water clarifier at a following point downstream? also, can you recomment a reference for the cationic and anionic clarifiers.
Thank you.

 

[Tipp2239]

Iradah, most oil in water emulsions are very fine oil droplets stabilised by surfactants. Surfactants can be charged molecules, you need break these away from the oil droplets, Simple use cationic in same process upstream in the emulsion leg. let it react, then po;lish off the water with anionic downsteam, maybe 10 metres away?. The anionic serve 2 purposes the react with positively charged surfactants like alkali metal salts, or alkaline earth salts, ot Nitrogen charged arising from asphaltenes or pyrroles eyc. Usually a ratio of 1 cationic to 3 anionic is a starting ratio. for very bad systems you can inject anionic water clarifiers directly into the separators furthest upsteam. you cannot inject cationics into the separators, too gummy. these are my applications.