Thanks everyone for their replies and comments. A multi-disciplinary team with experts of different backgrounds is carrying out a full failure investigation and we are in the final stages, but I wanted to see previous experiences and any pointers. Let's wait and see. Any further comments and...
Hi Everyone,
I have a high pressure water boiler leaked after very short upset in the boiler feed water pH: the pH was around 3 to 4! Has anybody come across such thing? What might be the causes? The steam condensate makeup is demineralized water (pH of demin water is within range). No leak of...
@SJones ... thanks for the reply. For answer 3, I never refer to that figure, if I have H2S, then it is sour for me ... might be over-conservative, but I have never understood that figure or ever found it of any practical use (at least to me)!
For answer 2, Inquiry #2006-01Q1: it says that "For...
Hi Everyone,
I have a length of piping (material falls under P No. 1 in ASME B31.3) that I am currently reviewing the corrosion circuits associated with them. I have noticed that SSC is defined as a possible damage which I tend to agree because the service is sour, but upon reviewing NACE...
Hi Everyone,
Does anybody know how ECE model deals with H2S? i.e. if H2S is present does it multiply the CO2 corrosion rate with a certain factor and gives the overall corrosion rate?
I want to understand how it deals with slightly sour and very sour systems (pCO2/pH2S > 500 and pCO2<pH2S <...
Hi Everyone,
Has anyone got any experience of using oil wetting agents to prevent water from stripping out from oil/crude and hence preventing MIC? Any references is well-appreciated.
Regards,
Corroneer
@alchemon, thanks for your replies.
Using corrosion inhibitor with coating is mandated by the client, but I wanted to:
1) understand the logic behind such requirement (I was guessing when I mentioned that the inhibitor will work on welds and holidays as the CP does).
2) explore other options as...
Hi,
One major oil company mandates the use of coating and chemical treatment! I guess their argument is that the corrosion inhibitor will work on coating failures and welds as the CP will do for the coating holidays! which is not proven as far as I know. I do not consider internal coatings as a...
@LittleInch, @SJones: The line will tie in to another bare carbon steel pipeline! so we need the injection unfortunately. I have tried to push for lined CS, but the injection is still needed for the other portion!
And for the oxygen, some of the water comes from collection pits.
@LittleInch … we are designing a new pipeline for "treated" oil and gas facility wastewater to injection wells. And the chemicals (types and dosages) were proposed by a chemical vendor.
@TugboatEng … I did not mean that we inject one and then the other … No, all of them should be injected continuously as you said. I meant which one should be the most upstream injection, then which one (i.e. the physical location of the injection point).
I usually do the following: the first...
@LittleInch, as you mentioned: "Only as good as the day it is done". Some companies substitute rigorous inspection with pressure tests and normally get a leak after a week or two and then started jumping around "but we pressure tested it and it was fine"!!!
I am looking for a document that outlines the best practice for injecting the different chemicals in a pipeline.
We have corrosion inhibitor, biocide, and oxygen scavenger that have to be injected in the pipeline. What is the first chemical to inject, the second and the last?
Regards,
Corroneer
