4 replies to this topic

[rajeevd]

Phosphoric acid was stored in a 304 SS tank for atleast 7-8 years and no problems were noticed. Last week we noticed that the acid stored in the tank (for 5-6 days) had a greenish color to it. This was all of a sudden. The acid stored in it prior to that incident was normal. We suspect this was metal leaching, so we sent out the sample for Nickel and iron analysis.

Two samples were submitted

1) retain sample of the acid from the week before.

2) the green colored sample

The results indicated that Nickel and Chromium content were 100 times higher ( from 4 ppm to 420 ppm) in the colored sample.

I find this strange that the tank had been in service for yrs and all of sudden we see this phenomena. Has anyone have this happened to them before?

Thanks for the insight.

[nico bibree]

Phosphoric acid was stored in a 304 SS tank for atleast 7-8 years and no problems were noticed. Last week we noticed that the acid stored in the tank (for 5-6 days) had a greenish color to it. This was all of a sudden. The acid stored in it prior to that incident was normal. We suspect this was metal leaching, so we sent out the sample for Nickel and iron analysis.

Two samples were submitted

1) retain sample of the acid from the week before.

2) the green colored sample

The results indicated that Nickel and Chromium content were 100 times higher ( from 4 ppm to 420 ppm) in the colored sample.

I find this strange that the tank had been in service for yrs and all of sudden we see this phenomena. Has anyone have this happened to them before?

Thanks for the insight.

[nico bibree]

I had exactly the same experience and am also at a loss what happened.
suggestions/ideas are more than welcome

Dear Sir (rajeevd)
I am trying to reach for this matter. Please contact me to exchange ideas.
Had written an e-mail a week ago.
Waiting your news, thank you in advance.

Evren Akal

P.S. e-mail: evren@levi.com.tr