Weak sulphuric and chlorides

[scorer]

Can anybody please help select MOC for stoage tank and pump for 5%wt sulphuric acid with chlorides at 85 degC, atmospheric pressure.

 

[Metalguy]

Sounds like you're getting into Hastelloy C 276 territory.

 

[hacksaw]

85 oC is quite hot. a number of supler duplex stainless alloys in the hotspots with rubber lined equip. and FRP piping and vessels used in the cooler areas to control the costs.

Hastelloy C-276 is an expensive option and is usually confined to various fittings that have a limited range of materials selections available.

Materials selection is critical, as you know that service is notorious for really agressive attack with just slight changes in the process chemistry. Good Luck,

 

[moltenmetal]

If the tank is atmospheric, there's no way I'd bother with high alloys- FRP will be far cheaper, and rather than being resistant to corrosion, the right resin will be essentially immune to corrosion by this mixture. If it's a huge tank, you may want to consider FRP-lined steel or concrete instead.

As far as pumps go, it depends on what pressure you need, the percent solids in the stream etc. 85 C is too hot to recommend the normal thermoplastics (though PVDF may work if your pressure requirements are very modest). You can get FRP mech seal centrificals and also PP or ETFE-lined centrificals with either seals or mag-drive, which are good to 150# class up to about 120 C. Innomag (

http://www.innomag.com)

makes a very good lined magdrive. Others include Goulds, Durco etc. These options are far cheaper than hastelloy or titanium.