MIC CORROSION or co2 wet corrosion(sweet corrosion)

[Ali Asghari]

Dear All.

We encountered to a pitting corrosion that led to loss of fluid in crude pipeline, so we prepared a sample and send it to lab.it must be mentioned that this corrosion happened after 6 

months from starting of production and there is possibility for existence of remained hydro test water and the chemical injection not to start any inhibitor injection with regarding in 

engineering design documents, availability of 95% inhibitor requested and warned for retained water to increase of pitting opportunity.

the lab concluded the result of this corrosion is MIC(SRB type) with doing of these tests: EDS/XRD/SRB test.
Now I have some doubts:
1.SRB or anaerobe bacteria can be survived & detected in air to reach Lab.

2.I know that to get conclusion by now is not possible but I want to know that are these tests enough or what is supposed to be done other tests to refuse co2 corrosion?

I have attached some results.

Regards.

[Muhammad Hussain]

Dear Ali, 

1. Yes it’s possible and you can take. Corrosion deposit , metal or perhaps in water to do the analysis. 

2. Can you send clear images of the sample, specially from pits. 

Chloride and Sulphide are different source and affect on MIC. 

Regards 

Muhammad 

Sent from my iPhone, Excuse Typos

--
https://materials-welding.blogspot.com/
https://www.linkedin.com/groups/122787
---
You received this message because you are subscribed to the Google Groups "Materials & Welding" group.
To unsubscribe from this group and stop receiving emails from it, send an email to materials-weld...@googlegroups.com.
Visit this group at https://groups.google.com/group/materials-welding.
For more options, visit https://groups.google.com/d/optout.

<20180702_164353.jpg>

<20180702_164522.jpg>

<20180702_164557.jpg>

<20180702_164704.jpg>

[Ali Asghari]

Dear Muhammad.

I have attached them.

I am only wondering that this corrosion with this rate may happen with detachable corrosion products by wetty co2 or h2s that affected by flow velocity.now how can we reach to this confidence or these results refuse this possibility.

Regards.

You received this message because you are subscribed to a topic in the Google Groups "Materials & Welding" group.
To unsubscribe from this topic, visit https://groups.google.com/d/topic/materials-welding/3fh9Rvt0j2E/unsubscribe.
To unsubscribe from this group and all its topics, send an email to materials-weld...@googlegroups.com.

[Muhammad Hussain]

It depends what is the current status of corrosion and how much damage is there? Also whats the materials of construction? 

Did your lab manage to measure the SRB and how much microbe is there? Without knowing this, its very hard to say what the material condition and how much time it will take to effect the material. 

Also depends on the MIC status as well. 

[Ali Asghari]

Unfortunately not.

I have attached them. I think this type of SRB test is qualitive.

On Tue, Jul 3, 2018 at 3:08 PM, 'Muhammad Hussain' via Materials & Welding <material...@googlegroups.com> wrote:

It depends what is the current status of corrosion and how much damage is there? Also whats the materials of construction? 

Did your lab manage to measure the SRB and how much microbe is there? Without knowing this, its very hard to say what the material condition and how much time it will take to effect the material. 

Also depends on the MIC status as well. 

On Tuesday, July 3, 2018, 8:13:37 PM GMT+10, Ali Asghari <asghar...@gmail.com> wrote:

Dear Muhammad.

I have attached them.

I am only wondering that this corrosion with this rate may happen with detachable corrosion products by wetty co2 or h2s that affected by flow velocity.now how can we reach to this confidence or these results refuse this possibility.

Regards.

On Tue, Jul 3, 2018 at 7:03 AM, 'Muhammad Hussain' via Materials & Welding <materials-welding@googlegroups.com> wrote:

Dear Ali, 

1. Yes it’s possible and you can take. Corrosion deposit , metal or perhaps in water to do the analysis. 

2. Can you send clear images of the sample, specially from pits. 

Chloride and Sulphide are different source and affect on MIC. 

Regards 

Muhammad 

Sent from my iPhone, Excuse Typos

On 2 Jul 2018, at 23:04, Ali Asghari <asghar...@gmail.com> wrote:

Dear All.

We encountered to a pitting corrosion that led to loss of fluid in crude pipeline, so we prepared a sample and send it to lab.it must be mentioned that this corrosion happened after 6 

months from starting of production and there is possibility for existence of remained hydro test water and the chemical injection not to start any inhibitor injection with regarding in 

engineering design documents, availability of 95% inhibitor requested and warned for retained water to increase of pitting opportunity.

the lab concluded the result of this corrosion is MIC(SRB type) with doing of these tests: EDS/XRD/SRB test.
Now I have some doubts:
1.SRB or anaerobe bacteria can be survived & detected in air to reach Lab.

2.I know that to get conclusion by now is not possible but I want to know that are these tests enough or what is supposed to be done other tests to refuse co2 corrosion?

I have attached some results.

Regards.

--
https://materials-welding.blogspot.com/
https://www.linkedin.com/groups/122787
---
You received this message because you are subscribed to the Google Groups "Materials & Welding" group.

To unsubscribe from this group and stop receiving emails from it, send an email to materials-welding+unsubscribe@googlegroups.com.

Visit this group at https://groups.google.com/group/materials-welding.
For more options, visit https://groups.google.com/d/optout.

<20180702_164353.jpg>

<20180702_164522.jpg>

<20180702_164557.jpg>

<20180702_164704.jpg>

--
https://materials-welding.blogspot.com/
https://www.linkedin.com/groups/122787
---
You received this message because you are subscribed to a topic in the Google Groups "Materials & Welding" group.
To unsubscribe from this topic, visit https://groups.google.com/d/topic/materials-welding/3fh9Rvt0j2E/unsubscribe.

To unsubscribe from this group and all its topics, send an email to materials-welding+unsubscribe@googlegroups.com.

Visit this group at https://groups.google.com/group/materials-welding.
For more options, visit https://groups.google.com/d/optout.

--
https://materials-welding.blogspot.com/
https://www.linkedin.com/groups/122787
---
You received this message because you are subscribed to the Google Groups "Materials & Welding" group.

To unsubscribe from this group and stop receiving emails from it, send an email to materials-welding+unsubscribe@googlegroups.com.

Visit this group at https://groups.google.com/group/materials-welding.
For more options, visit https://groups.google.com/d/optout.

--
https://materials-welding.blogspot.com/
https://www.linkedin.com/groups/122787
---

You received this message because you are subscribed to a topic in the Google Groups "Materials & Welding" group.
To unsubscribe from this topic, visit https://groups.google.com/d/topic/materials-welding/3fh9Rvt0j2E/unsubscribe.

To unsubscribe from this group and all its topics, send an email to materials-welding+unsubscribe@googlegroups.com.

[Muhammad Hussain]

This is not the method to measure SRB. There is a separate method called MSL for this and it’s long time study, min 6 months to measure the SRB and it’s status either it’s living, present or absent. By then you can take a decision and precaution for eliminating this. 

Sent from my iPhone, Excuse Typos

To unsubscribe from this group and stop receiving emails from it, send an email to materials-weld...@googlegroups.com.

Visit this group at https://groups.google.com/group/materials-welding.
For more options, visit https://groups.google.com/d/optout.

<Untitled.jpg>

[Ali Asghari]

Thank you so much for useful information.

Therefore you agree with me that these tests are not enough to conclude for SRB test.

Regardless of mentioned test, do you prescribe any other tests to consider possibility of co2 corrosion(mesa corrosion) or h2s pitting corrosion?

Regards.

<Untitled.jpg>

[PGoswami]

Hi Ali,

 

I assume your point is whether CO2 corrosion or MIC is the root cause  or one of the causes. We a few things to note:

1.       MIC typically occurs in stagnated condition.

2.       CO2 corrosion may happen  in both operating and stagnated condition, in presence of substantial amount of CO2 and water. Read the attached article for details. The details provided by you does not highlight any details related to CO2 corrosion, e.g. media, CO2 concentration, temperature etc.…

 

If  the pipeline contained stagnated water(without any inhibitor) for over 6 months , there’re every possibilities of occurrence of MIC.

 

Perhaps discussion of  these points with the Laboratory would be helpful. To answer your question SRB (causing MIC) could be aerobic and anaerobic both. The lab has to tell what’s generic form of the bacteria.

 

Thanks.

 

P.Goswami.P.Eng, IWE.

Welding & Metallurgical Specialist

Linkedin: https://www.linkedin.com/in/pradip-goswami-2999855/

Email:pgos...@quickclic.net,pradip....@gmail.com

--

https://materials-welding.blogspot.com/
https://www.linkedin.com/groups/122787
---
You received this message because you are subscribed to the Google Groups "Materials & Welding" group.

To unsubscribe from this group and stop receiving emails from it, send an email to materials-weld...@googlegroups.com.

[Ali Asghari]

Dear Anasua.

I am only wandering and believe that pitting may have some other causes in addition to SRB or is there a possibility the MIC mechanism isn't reason of that damage at all, due to result of mentioned tests can not say it with high confidence and considering of all conditions.

1. I agree with you but I think the lab said it that he assumed some of hydro test water remained and  during this gap between testing and production, SRB  have done it's work.

2.yes, you're right, PH& velocity & temperature have key roles that not wasn't considered by lab and again increase uncertainty.

Now if  it was possible or tendency, what other test would you suppose to be done to increase confidence or find precise result?(with regard to other similar lines are in production.)

And what have to be done about field monitoring or preventive and remedial actions with reminding that we don't know the exact root cause?

Regards.

 

To unsubscribe from this group and stop receiving emails from it, send an email to materials-welding+unsubscribe@googlegroups.com.

Visit this group at https://groups.google.com/group/materials-welding.
For more options, visit https://groups.google.com/d/optout.

--

https://materials-welding.blogspot.com/
https://www.linkedin.com/groups/122787
---

You received this message because you are subscribed to a topic in the Google Groups "Materials & Welding" group.
To unsubscribe from this topic, visit https://groups.google.com/d/topic/materials-welding/3fh9Rvt0j2E/unsubscribe.
To unsubscribe from this group and all its topics, send an email to materials-welding+unsubscribe@googlegroups.com.