Boiler Tubes Leak 7

[Corroneer]

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 ion exchange chemicals! What makes this a bit strange is that the leak occurred in only one boiler while the others (same operation, same age, same maintenance schedule, same everything!) did not suffer from any leaks although fed with the same BFW. The BFW is of course treated with oxygen scavenger and neutralizing amine after the deaerator.

Thanks in advance.

 

[mrfailure]

How can you possibly ask for crowdsourced opinions when you have not even done any metallurgical evaluation to characterize your leak? At minimum, you need to perform such a destructive evaluation to identify your failure mechanism and characterize the leak.

 

[bimr]

Have you reviewed this issue with the supplier that manages your chemical treatment program? What does he say?

 

The low pH value is a clear indication of a process control problem.
The corroded boiler steel (if that is what happened) was just the innocent bystander.

"Everyone is entitled to their own opinions, but they are not entitled to their own facts."

 

[MJCronin]

Corroneer,

Boilers are in a category of expensive equipment where careful examination of evidence points strongly to a reason for failure.

There have been many, many books, articles and papers written about boiler failures and conclusive evidence is always present.

https://www.amazon.com/Metallurgical-Failures-Fossil-Fired-Boilers/dp/0471558397

You have not offered any data or forensic evidence.....

https://www.amazon.com/Nalco-Boiler...ocphy=9015707&hvtargid=pla-493817988388&psc=1

Nothing will happen until you do ....

It seems that you already know this, but you are looking for excuses supported by random voices from eng-tips ....

You did not control water quality for some unknown period of time and now you are in a panic ...

The owners of the boiler could not care less about operations ...... until they face expensive repairs

It is now time to call in a seasoned expert, pay him for his services and get a report

Only my opinion ...

Anyone else ?


MJCronin
Sr. Process Engineer

 

[EdStainless]

MJC is speaking the truth here.
Don't rely on the OEM or your water treatment people.
Find and experienced independent consultant and pay him many thousands of dollars to come in and assist with the analysis.
He will require a bunch of testing be done, some of which is also costly.
Do it.
It is the only way that you will know enough to be able to prevent this in the future.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, consulting work welcomed

 

[Corroneer]

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 references are always welcome.

@bimr, the chemical supplier blames a "process upset".

 

Your water treatment supplier is not your friend. Think of them as your dealer.

"Everyone is entitled to their own opinions, but they are not entitled to their own facts."