Maximum Velocity in Pipe for 93% Sulfuric Acid 1

[AlbertaMecchie]

Hello,

I am designing a small piping system for handling 93% sulfuric acid and was wondering if there were some guidelines around maximum velocity in piping to prevent erosion from the acid.

Thanks,

 

[EdStainless]

Depends on the alloy and temp. If you are using carbon steel it is something like <2ft/sec and you would still need SS for elbows and valves.
Alloy 20 will handle 35ft/sec at 175F.
A good reference is MS-1:Sulfuric Acid from Materials Technology Institute of the Chemical Process Industries.
ISBN:1-57698-035-9
There is a second ed, but I am not sure that it is for sale.

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

 

[pierreick]

Hi,
Consider this resource to support your work
Pierre

 

[1503-44]

Waterhammer 15fps max.

 

[moltenmetal]

Use PVC and forget entirely about velocity as a worry.

 

[1503-44]

Waterhammer has no effect on PVC.

 

[TugboatEng]

Cavitation. Plastics are much more resistant not damage from cavitation.

 

[EdStainless]

[URL unfurl="true"]https://res.cloudinary.com/engineering-com/raw/upload/v1627404123/tips/H2SO4_rxqcom.docx[/url]

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

 

[moltenmetal]

OK @tugboateng, I assumed that economic velocities would be used, rather than going nuts. What I meant was that the creeping flows necessary to keep carbon steel and the like safe from this acid by passivating with a layer of iron sulphate are not required if you pick a material which is immune to corrosion by the acid, i.e. a nonmetallic material.