7 replies to this topic

[F.Sh]

Hi,

 

I have a problem in material selection for a test separator. the service is corrosive and sour. fluid entering the separator is a mixture of oil/water/gas. 

high corrosion rate and high H2S concentration is anticipated.

 

I would like to know if coating the shell (carbon steel) with glass flake epoxy is applicable or cladding with corrosion resistance alloy steel is only allowable.

 

operating condition:

T=30~60 °C

P=400 psi

salt in water: 150,000 ppm

 

what are the recommendations and conditions for application of coating?

 

thanks in advance for sharing your information in this regard

 

[Chemitofreak]

Hi,

 

I have not heard of glass flake epoxy as internal lining material for test separator in O&G facility, I have mostly seen corrosion resistant alloys, I maybe wrong though.

 

I am worried whether glass flake epoxy can handle that much pressure, contact the vendor or google about the pressure up to which it can be used.

 

Also, specify the contaminants like salts, H2S to the vendor while discussing 

[thorium90]

150k ppm is the chlorides only or the TDS?

 

I think glass flake epoxy can handle the the salt content.

The pressure, probably not so much. Can check.

I have seen glass flake epoxy coatings from Carboline being used. Can probably check with them.

 

Alternatively, with such a high concentration of chlorides, titanium would probably be the best albeit rather expensive option.

 

A cheaper option would be to go for GRP. It can be engineered to meet the pressure rating you require.

 

Another option would be to go for HDPE. PE100 or PE4710 can be used.

[F.Sh]

Thanks thorium90,

 

About non metallic materials you proposed, I'm not sour if those are fire resistant or if material fails during fire.

 

I also googled and found a vendor "BELZONA" which introduced a coating material claiming to be resistant to very sever condition (high temp, high pressure, high H2S and CO2).

 

I was wondering while such coating are available, why cladding of expensive alloy are commonly used. 

 

150000 ppm is TDS

H2S content is 0.3 %Wt

 

150k ppm is the chlorides only or the TDS?

 

I think glass flake epoxy can handle the the salt content.

The pressure, probably not so much. Can check.

I have seen glass flake epoxy coatings from Carboline being used. Can probably check with them.

 

Alternatively, with such a high concentration of chlorides, titanium would probably be the best albeit rather expensive option.

 

A cheaper option would be to go for GRP. It can be engineered to meet the pressure rating you require.

 

Another option would be to go for HDPE. PE100 or PE4710 can be used.

[thorium90]

I'm sure all materials will eventually fail when subject to fire. I think in this case, a tad more detail would be required to have a quantitative comparison rather than a qualitative comparison for the selection of materials. 

 

I guess the main point is that every material has its strengths and weaknesses. A good comparison would have aspects of both quantitative and qualitative aspects to provide a thorough evaluation. This thorough evaluation would then be truly helpful in helping you select the right material for your application.

 

If your application requires specific fire related properties, then I would suggest to add that to the evaluation criteria as well.

By adding more relevant criteria to your material selection matrix, you would be more assured of using the right material for the application.

 

Perhaps you can take your time to come up with your material selection criteria and post it here when you are ready.

Edited by thorium90, 24 April 2019 - 07:17 AM.

[F.Sh]

Based on my investigation, for my case, cladding with SS will be adequate for the design life the project. But lining/coating is much cheaper. I was searching to reach a basis about application of coating.

 

NACE RP 0181, has listed some kind of coating used for corrosion control in oil/gas production equipment and stated that the application of each coating has to be verified by laboratory testing and past field performance.

 

As much as I understood, for evaluation of coating, the only way is testing and manufacturer data.

[breizh]

Hi ,

You may consider Tantalum if Titanium is too expensive !

Tantalum cladding is an option .

Good luck

Breizh 

[thorium90]

I would say for evaluation of coatings or any material for that matter, real world references and experiences would be superior to any lab tests or manufacturer data...

Edited by thorium90, 24 April 2019 - 07:21 AM.