NACE RP0475 - Produced Water Handling

[rneill]

Does anyone know why NACE withdrew RP0475? Is there another similar standard out there (i.e., ISO) or is there no current accepted industry standard for these systems?

 

[strider6]

i'm not aware of any other standard on produced water material selection..
you can still find some good corrosion conference papers on the same issue..

Optimal Selection of Materials for Seawater Injection Systems: Testing in Deoxygenated Seawater

http://www.onepetro.org/mslib/servl...NACE-96593&soc=NACE&speAppNameCookie=ONEPETRO

S

Corrosion Prevention & Corrosion Control

 

[SJones]

NORSOK M-001 has a go at specifying materials for produced water and other waters.

It could be that RP0475 didn't get through a reaffirmation. I have to admit that I don't file the NACE e-mails that inform of standard withdrawals and the reasons for so doing.



Steve Jones
Materials & Corrosion Engineer

http://www.linkedin.com/pub/8/83b/b04

 

[rneill]

I took a look at Norsok M-001 but it doesn't have the same scope of materials and level of detail that did RP0475.

I also found and took a look at ISO 21457 (Draft) "Petroleum, Petrochemical and Natural Gas Industries - Materials Selection and Corrosion Control for Oil and Gas Production Systems" but it was similar to the Norsok document.

In particular, I was looking at valve bodies consisting of ASTM B148 C95500 (Nickel Aluminum Bronze) material which the old RP0475 listed as acceptable in produced water service, both aerated and non-aerated, providing there was less than 20 mg/L of H2S in solution.

Neither Norsok nor ISO seems to permit this material in produced water service.

 

[SJones]

Agreed. The NORSOK and draft NACE standards are a little weak. NORSOK because it is focused on offshore Norway and ISO because there are too many factions involved in its production.

The issue with NAB in sour water is conversion of the passive oxide layer to copper sulphide which then opens up the cathodic reaction to increase the corrosion rate. The question is: in oxygen free produced water, what will provide the species for the reduction reaction? Then there will be the erosional consideration as the copper sulphide is spongy and porous and flow through a valve could strip the film.

API RP 571 does state that 'copper alloys are usually resistant' to acidic sour water corrosion, however, the UK NPL advise against the use of NAB in 'sour water'.

http://www.npl.co.uk/upload/pdf/pumps.pdf

Tough call!



Steve Jones
Materials & Corrosion Engineer

http://www.linkedin.com/pub/8/83b/b04

 

[rneill]

Appreciate the additional info and I hadn't thought to look at 571. I'm going to stay away from the NAB for sour produced water and leave it for sweet produced water (per the old RP0475 guidelines).