sulfuric acid corrosion resistant coatings

[metallurgist5]

hello guys,

i am going to coat Carbon steel storage tanks containing sulfuric acid 60%, at 130 degrees centigrade, with a pressure of 4 bars.what do you suggest as the best coating considering corrosion resistance, ease of application and price?

many thanks to everyone,

 

[TVP]

Why would you want to use a coated, carbon steel tank?

 

[enmax]

There are no coatings that would be suitable - even if there were would you risk a break in the coating? You might consider building a plastic tank in a fluorinated polymer (but consult potential vendors first!). I'd be concerned about using carbon steel to contain 60% sulphuric at this temperature. As TVP says - why are you doing this? A high silicon cast iron would do this job with little risk. If you were to store the acid at higher concentrations (subject to certain precautions) you could leave the steel uncoated.

http://uk.linkedin.com/pub/terry-roberts/28/a9a/a10

 

[metallurgist5]

to TVP: thank you for your consideration. the reason is because the corrosion rate at the moment is higher than expected. the mentioned service conditions are highly corrosive and we have no other choice except coating the inside of the tanks. the wide range of coatings had made us confused a little, i really appreciate your comments.

 

[metallurgist5]

to enmax: thank you very much for your time and consideration. the fact is that unfortunately, the company has bought these tanks and at the moment, we want to try our best to coat the tanks rather than rebuilding them. till now, we are considering all the available coatings than can be chosen like : glass, TEFLON, Tantalum, PEEK, VITON, etc. i really appreciate your precise comments on both solutions: coating and rebuilding the tanks.

 

[TVP]

PTFE (Teflon) coatings are resistant to sulfuric acid. Here are some links:

http://www2.dupont.com/Clean_Technologies/es_MX/assets/downloads/Equipment_FAQs.pdf

http://www.polyprocessing.com/pdf/technical/ChemicalResistanceChart.pdf

http://www.xpress-link.net/ChemResult.asp

 

[metallurgist5]

to TVP: thank you once again for your reply. i checked all the links you provided. it seems the last link does not work properly, so its a great help if you just reupload it.
at the moment, we have put TEFLON on the first rank list till now. we are also considering the following at the same time :

1- Phenolics (Concentration= 50%- T=121C)
2- Perfluoroalkoxy/ PFA (Concentration= 10%-100%- T=232C)
3- Fluorinated Ethylene Propylene/ FEP (Concentration= 10%-100%- T=204C)
4- TEFLON/ PTFE (Concentration= 10%-100%- T=232C)
5- Tefzel/ ETFE (Concentration= 10%-100%- T=149C)
6- Halar /ECTFE (Concentration= 10%-70%- T=121C)
7- Fluoroelastomers (Concentration= 10%-98%- T=149C)

many thanks to your help.

 

[dmp3418]

Here is a product that is designed for acid storage in carbon steel tanks.

http://www.tnemec.com/product/view/Series-365-TankArmor

100% solids novolac epoxy. Our company has used this with success in the past. Corrosion in these tanks can be very accelerated, so a very dense, thick film lining would be required. Try giving the local Tnemec rep a call.

 

[corrosionman]

Metallurgist5.Your job is completely impossible.Phone Cleveland Corrosion Co in UK and I'll repeat what othereshave said already.
CM

 

[unclesyd]

There are two possibilities not eluded to in the above posts and they are Rubber and Lead Lined tanks. These tanks can be economical in many cases.
I don't have anyone now that specifically does Lead Lining. For Rubber Lined Tanks I would contact someone like Bittner to discuss your application.

http://bittnerindustries.com/capabilities.htm

 

[Jmoore1]

How big are these tanks... you could weld overlay or clad them as well.

 

[pennastik]

I hope you have already solved your problem. We solved some similar problems in UAE for an off-shore installation utilizing cold applied, polymeric repair compound. The name of product is Belzona.
In any case, forget a long life for your tanks.
Bye

 

[rustbuster]

There are some fairly good thermal spray alloys you might consider.