Piping to the process should be of schedule 80 carbon steel, or schedule 40, 316-stainless steel with slip on welded flanges.
Piping should be sized for an acid velocity of 3.5 feet/second or lower to minimize the erosive effects of the acid.
Care should be taken at both the design and operation stages to avoid liquid full sections of pipe between closed valves since the hydrogen produced by steel corrosion can cause dangerous pressures especially in warmer weather.
Quarter turn plug valves have been found to give good service with sulphuric acid.
The recommended type should have a flanged end ductile iron body with an alloy 20 plug or Teflon encapsulated plug and a Teflon lining.
Note that material selection is highly dependant upon the acid concentration - sometimes in counter-intuitive ways.
I'd be careful using carbon steel. If you do so, note that the Sch 80 piping suggested above is a corrosion allowance and you will lose material every year.
The conservative (but expensive) route is Alloy 20.
Carbon steel is fine for sulfuric acid in the 93% to 98% range that it is normally shipped at and is generally at a temperagture below 100 degrees F. It isn't likely that the truck or tank car is able to withstand more dilute acid than this. However, if your acid concentration is really as low as 90% concentration, you might have a problem with carbon steel. The metalurgical requirements for sulfuric acid at various concentrations is really variable. At 90%, you might need to use alloys with chromium and nickle or a nickel/molybdenum alloy of some type.
Ken Shumway
Ford, Bacon and Davis, LLC
So many recommendations and no one mentions plastics. PTFE, PVDF, and PP lined steel can all be used - Liner differences based upon acid concentration and temperature.
This guide is pretty comprehensive and may help..
Info above on the concentrations is good. Also note, sulphuric acid won't likely be used at these concentrations. Sulphuric acid is particularly hard on stainless or carbon steel during the mixing process.
I recall a case where the acid mixing station for the demineralizer had to be replaced after about 2 years of operation due to an eroded hole in a 1x2 reducer. The replacement piping only lasted 2 weeks! The welds were eaten away.
It turned out the initial piping was Alloy 20 and the replacement was 316SS.
