sulfuric acid tanks

[siretb]

Hello,

I am not too sure about what is best. For a 94% sulfuric acid storage (5m3), room temperature , what is best in terms of corrosion?
Carbon steel or stainlass? I know that carbon steel should be OK, but some people insist on stainless

I also have a second, related question. the breathing of the tank. Should it go through a dryer, to avoid any moisture in, or can we spare it. (European countries, air at 20°C)

Thank you in advance

 

[strider6]

At your operating conditions, room temperature, and acid concentration of 94% you can use carbon steel. There is a NACE Standard, NACE SP0294-2006, that specify materials for sulphuric acid tank.
NACE suggest a min of 3.2 mm of CA and a typical of 6.4 mm for conc between 88 to 99 %.
Ingress of moisture can cause severe corrosion at the liquid-air interface due to acid dilution. In the NACE standard you can find also requirement for Vent and measures to avoid moisture related problems.

http://www.techstreet.com/standards/NACE/SP0294_2006?product_id=1377226

http://www.corrosionist.com/corrosion_protection_sulfuric_acid.htm

S



Corrosion & Rust Prevention Control

 

[ErnieWise]

As srider6 says, carbon steel should be fine at room temperature with minimal corrosion. The acid will pickup some iron contamination from the corrosion that is occurring and this may or may not be a problem depending on what you're using the acid for. If iron contamination is an issue you have the option of either using stainless steel or installing an anodic protection system which can prevent corrosion in unlined carbon steel tanks and minimise iron contamination.

http://www.corrosionservice.co.uk

 

[siretb]

Thank you very much. Bernard