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Oil in water emulsion detection 1

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AlexWNZ

Electrical
Jul 3, 2019
9
NZ
Hi all,

Any one have any suggestions or products to use to detect oil in water emulsions?

Just having some issues with emulsions accumulating in our produced water systems that we'd like to be able to detect. We are looking at the tracerco profiler but am not sure if the stated 1% SG accuracy will be adequate.

Is there any other technologies out there that work (capacitive etc?)

Thanks!

Alex
 
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Is it really an emulsion, or is the oil just floating on the surface?
> Some sort of spectroscopic sensing would seem possible.
> Some sort of optical density sensing might be a similar, but slightly different approach

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! faq731-376 forum1529 Entire Forum list
 
A picture may be worth a 1,000 words here, if it's possible, because I'm not real sure whats going on. Is it a "rag" layer (stable emulsion) building up? They form between the oil and water layer and just hang around. Sometimes hard to get rid of. Do you have any surfactant-like molecules in the system?




Good luck,
Latexman

Engineers helping Engineers
 
We've been through the mill on these issues in Shell - if you've got stabilised oil droplets in the continuous water phase, you might have some luck with dp cells that have remote seals in their impulse lines. Keep clear of the AGAR interface detection probe - it simply doesnt work.
The root cause of these emulsions is the overdosing of corrosion inhibitor used for submarine pipeline corrosion management. You may find it an uphill climb trying to get these people to reduce injection rates, or switching to some other type of CI - dumped produced water quality is not a KPI for these guys.
 
Thanks All. Yes @Latexman it is a stable emulsion layer building up due to a combination of asphaltenes and CI (as per @georgeeverghese)

We don't have a coalescing stage in our produced water system (which we believe is one of the reasons for it accumulating in this part of the process). We can dose with emulsion breaker if we know it is there, the problem is how to detect it before it builds up too much and enters the next stage in the process.

I was also looking at the Hach FP 360 but the range (0-15ppm) of it is too low for the capabilities of this stage of the process... we need something that can detect and alarm/trip at around 1500-2500ppm.
 
Light scattering detectors may work but will be sensitive to other particulates, which may interfere with the desired measurement.
 
The test for oil and grease will detect all of the oil whether if it is a free oil or in emulsion "form".

It is better to have coalescing medium prior to the next stage of the process.

 
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